Provided by: toil_5.6.0-2_all
NAME
toil - Toil Documentation Toil is an open-source pure-Python workflow engine that lets people write better pipelines. Check out our website for a comprehensive list of Toil's features and read our paper to learn what Toil can do in the real world. Please subscribe to our low-volume announce mailing list and feel free to also join us on GitHub and Gitter. If using Toil for your research, please cite Vivian, J., Rao, A. A., Nothaft, F. A., Ketchum, C., Armstrong, J., Novak, A., … Paten, B. (2017). Toil enables reproducible, open source, big biomedical data analyses. Nature Biotechnology, 35(4), 314–316. http://doi.org/10.1038/nbt.3772
QUICKSTART EXAMPLES
Running a basic workflow A Toil workflow can be run with just two steps: 1. Copy and paste the following code block into a new file called helloWorld.py: from toil.common import Toil from toil.job import Job def helloWorld(message, memory="1G", cores=1, disk="1G"): return f"Hello, world!, here's a message: {message}" if __name__ == "__main__": parser = Job.Runner.getDefaultArgumentParser() options = parser.parse_args() options.clean = "always" with Toil(options) as toil: output = toil.start(Job.wrapFn(helloWorld, "You did it!")) print(output) 2. Specify the name of the job store and run the workflow: python helloWorld.py file:my-job-store Congratulations! You've run your first Toil workflow using the default Batch System, singleMachine, using the file job store. Toil uses batch systems to manage the jobs it creates. The singleMachine batch system is primarily used to prepare and debug workflows on a local machine. Once validated, try running them on a full-fledged batch system (see batchsysteminterface). Toil supports many different batch systems such as Apache Mesos and Grid Engine; its versatility makes it easy to run your workflow in all kinds of places. Toil is totally customizable! Run python helloWorld.py --help to see a complete list of available options. For something beyond a "Hello, world!" example, refer to A (more) real-world example. Running a basic CWL workflow The Common Workflow Language (CWL) is an emerging standard for writing workflows that are portable across multiple workflow engines and platforms. Running CWL workflows using Toil is easy. 1. Copy and paste the following code block into example.cwl: cwlVersion: v1.0 class: CommandLineTool baseCommand: echo stdout: output.txt inputs: message: type: string inputBinding: position: 1 outputs: output: type: stdout and this code into example-job.yaml: message: Hello world! 2. To run the workflow simply enter $ toil-cwl-runner example.cwl example-job.yaml Your output will be in output.txt: $ cat output.txt Hello world! To learn more about CWL, see the CWL User Guide (from where this example was shamelessly borrowed). To run this workflow on an AWS cluster have a look at Running a CWL Workflow on AWS. For information on using CWL with Toil see the section cwl Running a basic WDL workflow The Workflow Description Language (WDL) is another emerging language for writing workflows that are portable across multiple workflow engines and platforms. Running WDL workflows using Toil is still in alpha, and currently experimental. Toil currently supports basic workflow syntax (see wdl for more details and examples). Here we go over running a basic WDL helloworld workflow. 1. Copy and paste the following code block into wdl-helloworld.wdl: workflow write_simple_file { call write_file } task write_file { String message command { echo ${message} > wdl-helloworld-output.txt } output { File test = "wdl-helloworld-output.txt" } } and this code into ``wdl-helloworld.json``:: { "write_simple_file.write_file.message": "Hello world!" } 2. To run the workflow simply enter $ toil-wdl-runner wdl-helloworld.wdl wdl-helloworld.json Your output will be in wdl-helloworld-output.txt: $ cat wdl-helloworld-output.txt Hello world! To learn more about WDL, see the main WDL website . A (more) real-world example For a more detailed example and explanation, we've developed a sample pipeline that merge-sorts a temporary file. This is not supposed to be an efficient sorting program, rather a more fully worked example of what Toil is capable of. Running the example 1. Download the example code 2. Run it with the default settings: $ python sort.py file:jobStore The workflow created a file called sortedFile.txt in your current directory. Have a look at it and notice that it contains a whole lot of sorted lines! This workflow does a smart merge sort on a file it generates, fileToSort.txt. The sort is smart because each step of the process---splitting the file into separate chunks, sorting these chunks, and merging them back together---is compartmentalized into a job. Each job can specify its own resource requirements and will only be run after the jobs it depends upon have run. Jobs without dependencies will be run in parallel. NOTE: Delete fileToSort.txt before moving on to #3. This example introduces options that specify dimensions for fileToSort.txt, if it does not already exist. If it exists, this workflow will use the existing file and the results will be the same as #2. 3. Run with custom options: $ python sort.py file:jobStore \ --numLines=5000 \ --lineLength=10 \ --overwriteOutput=True \ --workDir=/tmp/ Here we see that we can add our own options to a Toil script. As noted above, the first two options, --numLines and --lineLength, determine the number of lines and how many characters are in each line. --overwriteOutput causes the current contents of sortedFile.txt to be overwritten, if it already exists. The last option, --workDir, is an option built into Toil to specify where temporary files unique to a job are kept. Describing the source code To understand the details of what's going on inside. Let's start with the main() function. It looks like a lot of code, but don't worry---we'll break it down piece by piece. def main(options=None): if not options: # deal with command line arguments parser = ArgumentParser() Job.Runner.addToilOptions(parser) parser.add_argument('--numLines', default=defaultLines, help='Number of lines in file to sort.', type=int) parser.add_argument('--lineLength', default=defaultLineLen, help='Length of lines in file to sort.', type=int) parser.add_argument("--fileToSort", help="The file you wish to sort") parser.add_argument("--outputFile", help="Where the sorted output will go") parser.add_argument("--overwriteOutput", help="Write over the output file if it already exists.", default=True) parser.add_argument("--N", dest="N", help="The threshold below which a serial sort function is used to sort file. " "All lines must of length less than or equal to N or program will fail", default=10000) parser.add_argument('--downCheckpoints', action='store_true', help='If this option is set, the workflow will make checkpoints on its way through' 'the recursive "down" part of the sort') parser.add_argument("--sortMemory", dest="sortMemory", help="Memory for jobs that sort chunks of the file.", default=None) parser.add_argument("--mergeMemory", dest="mergeMemory", help="Memory for jobs that collate results.", default=None) options = parser.parse_args() if not hasattr(options, "sortMemory") or not options.sortMemory: options.sortMemory = sortMemory if not hasattr(options, "mergeMemory") or not options.mergeMemory: options.mergeMemory = sortMemory # do some input verification sortedFileName = options.outputFile or "sortedFile.txt" if not options.overwriteOutput and os.path.exists(sortedFileName): print(f'Output file {sortedFileName} already exists. ' f'Delete it to run the sort example again or use --overwriteOutput=True') exit() fileName = options.fileToSort if options.fileToSort is None: # make the file ourselves fileName = 'fileToSort.txt' if os.path.exists(fileName): print(f'Sorting existing file: {fileName}') else: print(f'No sort file specified. Generating one automatically called: {fileName}.') makeFileToSort(fileName=fileName, lines=options.numLines, lineLen=options.lineLength) else: if not os.path.exists(options.fileToSort): raise RuntimeError("File to sort does not exist: %s" % options.fileToSort) if int(options.N) <= 0: raise RuntimeError("Invalid value of N: %s" % options.N) # Now we are ready to run with Toil(options) as workflow: sortedFileURL = 'file://' + os.path.abspath(sortedFileName) if not workflow.options.restart: sortFileURL = 'file://' + os.path.abspath(fileName) sortFileID = workflow.importFile(sortFileURL) sortedFileID = workflow.start(Job.wrapJobFn(setup, sortFileID, int(options.N), options.downCheckpoints, options=options, memory=sortMemory)) else: sortedFileID = workflow.restart() workflow.exportFile(sortedFileID, sortedFileURL) First we make a parser to process command line arguments using the argparse module. It's important that we add the call to Job.Runner.addToilOptions() to initialize our parser with all of Toil's default options. Then we add the command line arguments unique to this workflow, and parse the input. The help message listed with the arguments should give you a pretty good idea of what they can do. Next we do a little bit of verification of the input arguments. The option --fileToSort allows you to specify a file that needs to be sorted. If this option isn't given, it's here that we make our own file with the call to makeFileToSort(). Finally we come to the context manager that initializes the workflow. We create a path to the input file prepended with 'file://' as per the documentation for toil.common.Toil() when staging a file that is stored locally. Notice that we have to check whether or not the workflow is restarting so that we don't import the file more than once. Finally we can kick off the workflow by calling toil.common.Toil.start() on the job setup. When the workflow ends we capture its output (the sorted file's fileID) and use that in toil.common.Toil.exportFile() to move the sorted file from the job store back into "userland". Next let's look at the job that begins the actual workflow, setup. def setup(job, inputFile, N, downCheckpoints, options): """ Sets up the sort. Returns the FileID of the sorted file """ RealtimeLogger.info("Starting the merge sort") return job.addChildJobFn(down, inputFile, N, 'root', downCheckpoints, options = options, preemptable=True, memory=sortMemory).rv() setup really only does two things. First it writes to the logs using Job.log() and then calls addChildJobFn(). Child jobs run directly after the current job. This function turns the 'job function' down into an actual job and passes in the inputs including an optional resource requirement, memory. The job doesn't actually get run until the call to Job.rv(). Once the job down finishes, its output is returned here. Now we can look at what down does. def down(job, inputFileStoreID, N, path, downCheckpoints, options, memory=sortMemory): """ Input is a file, a subdivision size N, and a path in the hierarchy of jobs. If the range is larger than a threshold N the range is divided recursively and a follow on job is then created which merges back the results else the file is sorted and placed in the output. """ RealtimeLogger.info("Down job starting: %s" % path) # Read the file inputFile = job.fileStore.readGlobalFile(inputFileStoreID, cache=False) length = os.path.getsize(inputFile) if length > N: # We will subdivide the file RealtimeLogger.critical("Splitting file: %s of size: %s" % (inputFileStoreID, length)) # Split the file into two copies midPoint = getMidPoint(inputFile, 0, length) t1 = job.fileStore.getLocalTempFile() with open(t1, 'w') as fH: fH.write(copySubRangeOfFile(inputFile, 0, midPoint+1)) t2 = job.fileStore.getLocalTempFile() with open(t2, 'w') as fH: fH.write(copySubRangeOfFile(inputFile, midPoint+1, length)) # Call down recursively. By giving the rv() of the two jobs as inputs to the follow-on job, up, # we communicate the dependency without hindering concurrency. result = job.addFollowOnJobFn(up, job.addChildJobFn(down, job.fileStore.writeGlobalFile(t1), N, path + '/0', downCheckpoints, checkpoint=downCheckpoints, options=options, preemptable=True, memory=options.sortMemory).rv(), job.addChildJobFn(down, job.fileStore.writeGlobalFile(t2), N, path + '/1', downCheckpoints, checkpoint=downCheckpoints, options=options, preemptable=True, memory=options.mergeMemory).rv(), path + '/up', preemptable=True, options=options, memory=options.sortMemory).rv() else: # We can sort this bit of the file RealtimeLogger.critical("Sorting file: %s of size: %s" % (inputFileStoreID, length)) # Sort the copy and write back to the fileStore shutil.copyfile(inputFile, inputFile + '.sort') sort(inputFile + '.sort') result = job.fileStore.writeGlobalFile(inputFile + '.sort') RealtimeLogger.info("Down job finished: %s" % path) return result Down is the recursive part of the workflow. First we read the file into the local filestore by calling job.fileStore.readGlobalFile(). This puts a copy of the file in the temp directory for this particular job. This storage will disappear once this job ends. For a detailed explanation of the filestore, job store, and their interfaces have a look at managingFiles. Next down checks the base case of the recursion: is the length of the input file less than N (remember N was an option we added to the workflow in main)? In the base case, we just sort the file, and return the file ID of this new sorted file. If the base case fails, then the file is split into two new tempFiles using job.fileStore.getLocalTempFile() and the helper function copySubRangeOfFile. Finally we add a follow on Job up with job.addFollowOnJobFn(). We've already seen child jobs. A follow-on Job is a job that runs after the current job and all of its children (and their children and follow-ons) have completed. Using a follow-on makes sense because up is responsible for merging the files together and we don't want to merge the files together until we know they are sorted. Again, the return value of the follow-on job is requested using Job.rv(). Looking at up def up(job, inputFileID1, inputFileID2, path, options, memory=sortMemory): """ Merges the two files and places them in the output. """ RealtimeLogger.info("Up job starting: %s" % path) with job.fileStore.writeGlobalFileStream() as (fileHandle, outputFileStoreID): fileHandle = codecs.getwriter('utf-8')(fileHandle) with job.fileStore.readGlobalFileStream(inputFileID1) as inputFileHandle1: inputFileHandle1 = codecs.getreader('utf-8')(inputFileHandle1) with job.fileStore.readGlobalFileStream(inputFileID2) as inputFileHandle2: inputFileHandle2 = codecs.getreader('utf-8')(inputFileHandle2) RealtimeLogger.info("Merging %s and %s to %s" % (inputFileID1, inputFileID2, outputFileStoreID)) merge(inputFileHandle1, inputFileHandle2, fileHandle) # Cleanup up the input files - these deletes will occur after the completion is successful. job.fileStore.deleteGlobalFile(inputFileID1) job.fileStore.deleteGlobalFile(inputFileID2) RealtimeLogger.info("Up job finished: %s" % path) return outputFileStoreID we see that the two input files are merged together and the output is written to a new file using job.fileStore.writeGlobalFileStream(). After a little cleanup, the output file is returned. Once the final up finishes and all of the rv() promises are fulfilled, main receives the sorted file's ID which it uses in exportFile to send it to the user. There are other things in this example that we didn't go over such as checkpoints and the details of much of the api. At the end of the script the lines if __name__ == '__main__' main() are included to ensure that the main function is only run once in the '__main__' process invoked by you, the user. In Toil terms, by invoking the script you created the leader process in which the main() function is run. A worker process is a separate process whose sole purpose is to host the execution of one or more jobs defined in that script. In any Toil workflow there is always one leader process, and potentially many worker processes. When using the single-machine batch system (the default), the worker processes will be running on the same machine as the leader process. With full-fledged batch systems like Mesos the worker processes will typically be started on separate machines. The boilerplate ensures that the pipeline is only started once---on the leader---but not when its job functions are imported and executed on the individual workers. Typing python sort.py --help will show the complete list of arguments for the workflow which includes both Toil's and ones defined inside sort.py. A complete explanation of Toil's arguments can be found in commandRef. Logging By default, Toil logs a lot of information related to the current environment in addition to messages from the batch system and jobs. This can be configured with the --logLevel flag. For example, to only log CRITICAL level messages to the screen: $ python sort.py file:jobStore \ --logLevel=critical \ --overwriteOutput=True This hides most of the information we get from the Toil run. For more detail, we can run the pipeline with --logLevel=debug to see a comprehensive output. For more information, see workflowOptions. Error Handling and Resuming Pipelines With Toil, you can recover gracefully from a bug in your pipeline without losing any progress from successfully completed jobs. To demonstrate this, let's add a bug to our example code to see how Toil handles a failure and how we can resume a pipeline after that happens. Add a bad assertion at line 52 of the example (the first line of down()): def down(job, inputFileStoreID, N, downCheckpoints, memory=sortMemory): ... assert 1 == 2, "Test error!" When we run the pipeline, Toil will show a detailed failure log with a traceback: $ python sort.py file:jobStore ... ---TOIL WORKER OUTPUT LOG--- ... m/j/jobonrSMP Traceback (most recent call last): m/j/jobonrSMP File "toil/src/toil/worker.py", line 340, in main m/j/jobonrSMP job._runner(jobGraph=jobGraph, jobStore=jobStore, fileStore=fileStore) m/j/jobonrSMP File "toil/src/toil/job.py", line 1270, in _runner m/j/jobonrSMP returnValues = self._run(jobGraph, fileStore) m/j/jobonrSMP File "toil/src/toil/job.py", line 1217, in _run m/j/jobonrSMP return self.run(fileStore) m/j/jobonrSMP File "toil/src/toil/job.py", line 1383, in run m/j/jobonrSMP rValue = userFunction(*((self,) + tuple(self._args)), **self._kwargs) m/j/jobonrSMP File "toil/example.py", line 30, in down m/j/jobonrSMP assert 1 == 2, "Test error!" m/j/jobonrSMP AssertionError: Test error! If we try and run the pipeline again, Toil will give us an error message saying that a job store of the same name already exists. By default, in the event of a failure, the job store is preserved so that the workflow can be restarted, starting from the previously failed jobs. We can restart the pipeline by running $ python sort.py file:jobStore \ --restart \ --overwriteOutput=True We can also change the number of times Toil will attempt to retry a failed job: $ python sort.py file:jobStore \ --retryCount 2 \ --restart \ --overwriteOutput=True You'll now see Toil attempt to rerun the failed job until it runs out of tries. --retryCount is useful for non-systemic errors, like downloading a file that may experience a sporadic interruption, or some other non-deterministic failure. To successfully restart our pipeline, we can edit our script to comment out line 30, or remove it, and then run $ python sort.py file:jobStore \ --restart \ --overwriteOutput=True The pipeline will run successfully, and the job store will be removed on the pipeline's completion. Collecting Statistics Please see the cli_status section for more on gathering runtime and resource info on jobs. Launching a Toil Workflow in AWS After having installed the aws extra for Toil during the installation-ref and set up AWS (see prepareAWS), the user can run the basic helloWorld.py script (Running a basic workflow) on a VM in AWS just by modifying the run command. Note that when running in AWS, users can either run the workflow on a single instance or run it on a cluster (which is running across multiple containers on multiple AWS instances). For more information on running Toil workflows on a cluster, see runningAWS. Also! Remember to use the destroyCluster command when finished to destroy the cluster! Otherwise things may not be cleaned up properly. 1. Launch a cluster in AWS using the launchCluster command: $ toil launch-cluster <cluster-name> \ --keyPairName <AWS-key-pair-name> \ --leaderNodeType t2.medium \ --zone us-west-2a The arguments keyPairName, leaderNodeType, and zone are required to launch a cluster. 2. Copy helloWorld.py to the /tmp directory on the leader node using the rsyncCluster command: $ toil rsync-cluster --zone us-west-2a <cluster-name> helloWorld.py :/tmp Note that the command requires defining the file to copy as well as the target location on the cluster leader node. 3. Login to the cluster leader node using the sshCluster command: $ toil ssh-cluster --zone us-west-2a <cluster-name> Note that this command will log you in as the root user. 4. Run the Toil script in the cluster: $ python /tmp/helloWorld.py aws:us-west-2:my-S3-bucket In this particular case, we create an S3 bucket called my-S3-bucket in the us-west-2 availability zone to store intermediate job results. Along with some other INFO log messages, you should get the following output in your terminal window: Hello, world!, here's a message: You did it!. 5. Exit from the SSH connection. $ exit 6. Use the destroyCluster command to destroy the cluster: $ toil destroy-cluster --zone us-west-2a <cluster-name> Note that this command will destroy the cluster leader node and any resources created to run the job, including the S3 bucket. Running a CWL Workflow on AWS After having installed the aws and cwl extras for Toil during the installation-ref and set up AWS (see prepareAWS), the user can run a CWL workflow with Toil on AWS. Also! Remember to use the destroyCluster command when finished to destroy the cluster! Otherwise things may not be cleaned up properly. 1. First launch a node in AWS using the launchCluster command: $ toil launch-cluster <cluster-name> \ --keyPairName <AWS-key-pair-name> \ --leaderNodeType t2.medium \ --zone us-west-2a 2. Copy example.cwl and example-job.yaml from the CWL example to the node using the rsyncCluster command: toil rsync-cluster --zone us-west-2a <cluster-name> example.cwl :/tmp toil rsync-cluster --zone us-west-2a <cluster-name> example-job.yaml :/tmp 3. SSH into the cluster's leader node using the sshCluster utility: $ toil ssh-cluster --zone us-west-2a <cluster-name> 4. Once on the leader node, it's a good idea to update and install the following: sudo apt-get update sudo apt-get -y upgrade sudo apt-get -y dist-upgrade sudo apt-get -y install git sudo pip install mesos.cli 5. Now create a new virtualenv with the --system-site-packages option and activate: virtualenv --system-site-packages venv source venv/bin/activate 6. Now run the CWL workflow: (venv) $ toil-cwl-runner \ --provisioner aws \ --jobStore aws:us-west-2a:any-name \ /tmp/example.cwl /tmp/example-job.yaml TIP: When running a CWL workflow on AWS, input files can be provided either on the local file system or in S3 buckets using s3:// URI references. Final output files will be copied to the local file system of the leader node. 7. Finally, log out of the leader node and from your local computer, destroy the cluster: $ toil destroy-cluster --zone us-west-2a <cluster-name> Running a Workflow with Autoscaling - Cactus Cactus is a reference-free, whole-genome multiple alignment program that can be run on any of the cloud platforms Toil supports. NOTE: Cloud Independence: This example provides a "cloud agnostic" view of running Cactus with Toil. Most options will not change between cloud providers. However, each provisioner has unique inputs for --leaderNodeType, --nodeType and --zone. We recommend the following: ┌─────────────────┬────────────────┬────────────┬───────────────┐ │Option │ Used in │ AWS │ Google │ ├─────────────────┼────────────────┼────────────┼───────────────┤ │--leaderNodeType │ launch-cluster │ t2.medium │ n1-standard-1 │ ├─────────────────┼────────────────┼────────────┼───────────────┤ │--zone │ launch-cluster │ us-west-2a │ us-west1-a │ ├─────────────────┼────────────────┼────────────┼───────────────┤ │--zone │ cactus │ us-west-2 │ │ ├─────────────────┼────────────────┼────────────┼───────────────┤ │--nodeType │ cactus │ c3.4xlarge │ n1-standard-8 │ └─────────────────┴────────────────┴────────────┴───────────────┘ When executing toil launch-cluster with gce specified for --provisioner, the option --boto must be specified and given a path to your .boto file. See runningGCE for more information about the --boto option. Also! Remember to use the destroyCluster command when finished to destroy the cluster! Otherwise things may not be cleaned up properly. 1. Download pestis.tar.gz 2. Launch a leader node using the launchCluster command: (venv) $ toil launch-cluster <cluster-name> \ --provisioner <aws, gce> \ --keyPairName <key-pair-name> \ --leaderNodeType <type> \ --zone <zone> NOTE: A Helpful Tip When using AWS, setting the environment variable eliminates having to specify the --zone option for each command. This will be supported for GCE in the future. $ export TOIL_AWS_ZONE=us-west-2c 3. Create appropriate directory for uploading files: $ toil ssh-cluster --provisioner <aws, gce> <cluster-name> $ mkdir /root/cact_ex $ exit 4. Copy the required files, i.e., seqFile.txt (a text file containing the locations of the input sequences as well as their phylogenetic tree, see here), organisms' genome sequence files in FASTA format, and configuration files (e.g. blockTrim1.xml, if desired), up to the leader node: $ toil rsync-cluster --provisioner <aws, gce> <cluster-name> pestis-short-aws-seqFile.txt :/root/cact_ex $ toil rsync-cluster --provisioner <aws, gce> <cluster-name> GCF_000169655.1_ASM16965v1_genomic.fna :/root/cact_ex $ toil rsync-cluster --provisioner <aws, gce> <cluster-name> GCF_000006645.1_ASM664v1_genomic.fna :/root/cact_ex $ toil rsync-cluster --provisioner <aws, gce> <cluster-name> GCF_000182485.1_ASM18248v1_genomic.fna :/root/cact_ex $ toil rsync-cluster --provisioner <aws, gce> <cluster-name> GCF_000013805.1_ASM1380v1_genomic.fna :/root/cact_ex $ toil rsync-cluster --provisioner <aws, gce> <cluster-name> setup_leaderNode.sh :/root/cact_ex $ toil rsync-cluster --provisioner <aws, gce> <cluster-name> blockTrim1.xml :/root/cact_ex $ toil rsync-cluster --provisioner <aws, gce> <cluster-name> blockTrim3.xml :/root/cact_ex 5. Log in to the leader node: $ toil ssh-cluster --provisioner <aws, gce> <cluster-name> 6. Set up the environment of the leader node to run Cactus: $ bash /root/cact_ex/setup_leaderNode.sh $ source cact_venv/bin/activate (cact_venv) $ cd cactus (cact_venv) $ pip install --upgrade . 7. Run Cactus as an autoscaling workflow: (cact_venv) $ TOIL_APPLIANCE_SELF=quay.io/ucsc_cgl/toil:3.14.0 cactus \ --provisioner <aws, gce> \ --nodeType <type> \ --maxNodes 2 \ --minNodes 0 \ --retry 10 \ --batchSystem mesos \ --logDebug \ --logFile /logFile_pestis3 \ --configFile \ /root/cact_ex/blockTrim3.xml <aws, google>:<zone>:cactus-pestis \ /root/cact_ex/pestis-short-aws-seqFile.txt \ /root/cact_ex/pestis_output3.hal NOTE: Pieces of the Puzzle: TOIL_APPLIANCE_SELF=quay.io/ucsc_cgl/toil:3.14.0 --- specifies the version of Toil being used, 3.14.0; if the latest one is desired, please eliminate. --nodeType --- determines the instance type used for worker nodes. The instance type specified here must be on the same cloud provider as the one specified with --leaderNodeType --maxNodes 2 --- creates up to two instances of the type specified with --nodeType and launches Mesos worker containers inside them. --logDebug --- equivalent to --logLevel DEBUG. --logFile /logFile_pestis3 --- writes logs in a file named logFile_pestis3 under / folder. --configFile --- this is not required depending on whether a specific configuration file is intended to run the alignment. <aws, google>:<zone>:cactus-pestis --- creates a bucket, named cactus-pestis, with the specified cloud provider to store intermediate job files and metadata. NOTE: If you want to use a GCE-based jobstore, specify google here, not gce. The result file, named pestis_output3.hal, is stored under /root/cact_ex folder of the leader node. Use cactus --help to see all the Cactus and Toil flags available. 8. Log out of the leader node: (cact_venv) $ exit 9. Download the resulted output to local machine: (venv) $ toil rsync-cluster \ --provisioner <aws, gce> <cluster-name> \ :/root/cact_ex/pestis_output3.hal \ <path-of-folder-on-local-machine> 10. Destroy the cluster: (venv) $ toil destroy-cluster --provisioner <aws, gce> <cluster-name>
INTRODUCTION
Toil runs in various environments, including locally and in the cloud (Amazon Web Services and Google Compute Engine). Toil also supports two DSLs: CWL and (Amazon Web Services and Google Compute Engine). Toil also supports two DSLs: CWL and WDL (experimental). Toil is built in a modular way so that it can be used on lots of different systems, and with different configurations. The three configurable pieces are the · jobStoreInterface: A filepath or url that can host and centralize all files for a workflow (e.g. a local folder, or an AWS s3 bucket url). · batchSystemInterface: Specifies either a local single-machine or a currently supported HPC environment (lsf, parasol, mesos, slurm, torque, htcondor, kubernetes, or grid_engine). Mesos is a special case, and is launched for cloud environments. · Provisioner: For running in the cloud only. This specifies which cloud provider provides instances to do the "work" of your workflow. Job Store The job store is a storage abstraction which contains all of the information used in a Toil run. This centralizes all of the files used by jobs in the workflow and also the details of the progress of the run. If a workflow crashes or fails, the job store contains all of the information necessary to resume with minimal repetition of work. Several different job stores are supported, including the file job store and cloud job stores. File Job Store The file job store is for use locally, and keeps the workflow information in a directory on the machine where the workflow is launched. This is the simplest and most convenient job store for testing or for small runs. For an example that uses the file job store, see quickstart. Cloud Job Stores Toil currently supports the following cloud storage systems as job stores: · awsJobStore: An AWS S3 bucket formatted as "aws:<zone>:<bucketname>" where only numbers, letters, and dashes are allowed in the bucket name. Example: aws:us-west-2:my-aws-jobstore-name. · googleJobStore: A Google Cloud Storage bucket formatted as "gce:<zone>:<bucketname>" where only numbers, letters, and dashes are allowed in the bucket name. Example: gce:us-west2-a:my-google-jobstore-name. These use cloud buckets to house all of the files. This is useful if there are several different worker machines all running jobs that need to access the job store. Batch System A Toil batch system is either a local single-machine (one computer) or a currently supported HPC cluster of computers (lsf, parasol, mesos, slurm, torque, htcondor, or grid_engine). Mesos is a special case, and is launched for cloud environments. These environments manage individual worker nodes under a leader node to process the work required in a workflow. The leader and its workers all coordinate their tasks and files through a centralized job store location. See batchSystemInterface for a more detailed description of different batch systems. Provisioner The Toil provisioner provides a tool set for running a Toil workflow on a particular cloud platform. The clusterRef are command line tools used to provision nodes in your desired cloud platform. They allows you to launch nodes, ssh to the leader, and rsync files back and forth. For detailed instructions for using the provisioner see runningAWS or runningGCE.
COMMANDLINE OPTIONS
A quick way to see all of Toil's commandline options is by executing the following on a toil script: $ toil example.py --help For a basic toil workflow, Toil has one mandatory argument, the job store. All other arguments are optional. The Job Store Running toil scripts requires a filepath or url to a centralizing location for all of the files of the workflow. This is Toil's one required positional argument: the job store. To use the quickstart example, if you're on a node that has a large /scratch volume, you can specify that the jobstore be created there by executing: python HelloWorld.py /scratch/my-job-store, or more explicitly, python HelloWorld.py file:/scratch/my-job-store. Syntax for specifying different job stores: Local: file:job-store-name AWS: aws:region-here:job-store-name Google: google:projectID-here:job-store-name Different types of job store options can be found below. Commandline Options Core Toil Options --workDir WORKDIR Absolute path to directory where temporary files generated during the Toil run should be placed. Temp files and folders, as well as standard output and error from batch system jobs (unless --noStdOutErr), will be placed in a directory toil-<workflowID> within workDir. The workflowID is generated by Toil and will be reported in the workflow logs. Default is determined by the variables (TMPDIR, TEMP, TMP) via mkdtemp. This directory needs to exist on all machines running jobs; if capturing standard output and error from batch system jobs is desired, it will generally need to be on a shared file system. --noStdOutErr Do not capture standard output and error from batch system jobs. --stats Records statistics about the toil workflow to be used by 'toil stats'. --clean=STATE Determines the deletion of the jobStore upon completion of the program. Choices: 'always', 'onError','never', or 'onSuccess'. The -\-stats option requires information from the jobStore upon completion so the jobStore will never be deleted with that flag. If you wish to be able to restart the run, choose 'never' or 'onSuccess'. Default is 'never' if stats is enabled, and 'onSuccess' otherwise --cleanWorkDir STATE Determines deletion of temporary worker directory upon completion of a job. Choices: 'always', 'never', 'onSuccess'. Default = always. WARNING: This option should be changed for debugging only. Running a full pipeline with this option could fill your disk with intermediate data. --clusterStats FILEPATH If enabled, writes out JSON resource usage statistics to a file. The default location for this file is the current working directory, but an absolute path can also be passed to specify where this file should be written. This option only applies when using scalable batch systems. --restart If -\-restart is specified then will attempt to restart existing workflow at the location pointed to by the -\-jobStore option. Will raise an exception if the workflow does not exist. Logging Options Toil hides stdout and stderr by default except in case of job failure. Log levels in toil are based on priority from the logging module: --logOff Only CRITICAL log levels are shown. Equivalent to --logLevel=OFF or --logLevel=CRITICAL. --logCritical Only CRITICAL log levels are shown. Equivalent to --logLevel=OFF or --logLevel=CRITICAL. --logError Only ERROR, and CRITICAL log levels are shown. Equivalent to --logLevel=ERROR. --logWarning Only WARN, ERROR, and CRITICAL log levels are shown. Equivalent to --logLevel=WARNING. --logInfo All log statements are shown, except DEBUG. Equivalent to --logLevel=INFO. --logDebug All log statements are shown. Equivalent to --logLevel=DEBUG. --logLevel=LOGLEVEL May be set to: OFF (or CRITICAL), ERROR, WARN (or WARNING), INFO, or DEBUG. --logFile FILEPATH Specifies a file path to write the logging output to. --rotatingLogging Turn on rotating logging, which prevents log files from getting too big (set using --maxLogFileSize BYTESIZE). --maxLogFileSize BYTESIZE Sets the maximum log file size in bytes (--rotatingLogging must be active). Batch System Options --batchSystem BATCHSYSTEM The type of batch system to run the job(s) with, currently can be one of lsf, mesos, slurm, torque, htcondor, single_machine, parasol, grid_engine, kubernetes, tes. (default: single_machine) --parasolCommand PARASOLCOMMAND The name or path of the parasol program. Will be looked up on PATH unless it starts with a slash. (default: parasol) --parasolMaxBatches PARASOLMAXBATCHES Maximum number of job batches the Parasol batch is allowed to create. One batch is created for jobs with a unique set of resource requirements. (default: 1000) — mesosEndpoint MESOSENDPOINT The host and port of the Mesos server separated by a colon. (default: <leader IP>:5050) --kubernetesHostPath KUBERNETES_HOST_PATH A path on Kubernetes hosts that will be mounted as the Toil work directory in the workers, to allow for shared caching. --kubernetesOwner KUBERNETES_OWNER A name prefix for easy identification of Kubernetes jobs. If not set, Toil will use the current user name. --kubernetesServiceAccount KUBERNETES_SERVICE_ACCOUNT A service account name to apply when creating Kubernetes pods. --tesEndpoint TES_ENDPOINT The http(s) URL of the TES server. (default: http://<leader IP>:8000) --tesUser TES_USER User name to use for basic authentication to TES server. --tesPassword TES_PASSWORD Password to use for basic authentication to TES server. --tesBearerToken TES_BEARER_TOKEN Bearer token to use for authentication to TES server. --scale SCALE A scaling factor to change the value of all submitted tasks' submitted cores. Used in singleMachine batch system. Useful for running workflows on smaller machines than they were designed for, by setting a value less than 1. (default: 1) --linkImports When using Toil's importFile function for staging, input files are copied to the job store. Specifying this option saves space by sym-linking imported files. As long as caching is enabled Toil will protect the file automatically by changing the permissions to read-only. --coalesceStatusCalls Coalese status calls to prevent the batch system from being overloaded. Currently only supported for LSF. Autoscaling Options --provisioner CLOUDPROVIDER The provisioner for cluster auto-scaling. The currently supported choices are 'aws' or 'gce'. The default is None. --nodeTypes NODETYPES Specifies a list of comma-separated node types, each of which is composed of slash-separated instance types, and an optional spot bid set off by a colon, making the node type preemptable. Instance types may appear in multiple node types, and the same node type may appear as both preemptable and non-preemptable. Valid argument specifying two node types: c5.4xlarge/c5a.4xlarge:0.42,t2.large Node types: c5.4xlarge/c5a.4xlarge:0.42 and t2.large Instance types: c5.4xlarge, c5a.4xlarge, and t2.large Semantics: Bid $0.42/hour for either c5.4xlarge or c5a.4xlarge instances, treated interchangeably, while they are available at that price, and buy t2.large instances at full price --minNodes MINNODES Minimum number of nodes of each type in the cluster, if using auto-scaling. This should be provided as a comma-separated list of the same length as the list of node types. default=0 --maxNodes MAXNODES Maximum number of nodes of each type in the cluster, if using autoscaling, provided as a comma-separated list. The first value is used as a default if the list length is less than the number of nodeTypes. default=10 --preemptableCompensation PREEMPTABLECOMPENSATION The preference of the autoscaler to replace preemptable nodes with non-preemptable nodes, when preemptable nodes cannot be started for some reason. Defaults to 0.0. This value must be between 0.0 and 1.0, inclusive. A value of 0.0 disables such compensation, a value of 0.5 compensates two missing preemptable nodes with a non-preemptable one. A value of 1.0 replaces every missing pre-emptable node with a non-preemptable one. --nodeStorage NODESTORAGE Specify the size of the root volume of worker nodes when they are launched in gigabytes. You may want to set this if your jobs require a lot of disk space. The default value is 50. --nodeStorageOverrides NODESTORAGEOVERRIDES Comma-separated list of nodeType:nodeStorage that are used to override the default value from --nodeStorage for the specified nodeType(s). This is useful for heterogeneous jobs where some tasks require much more disk than others. --metrics Enable the prometheus/grafana dashboard for monitoring CPU/RAM usage, queue size, and issued jobs. --defaultMemory INT The default amount of memory to request for a job. Only applicable to jobs that do not specify an explicit value for this requirement. Standard suffixes like K, Ki, M, Mi, G or Gi are supported. Default is 2.0G --defaultCores FLOAT The default number of CPU cores to dedicate a job. Only applicable to jobs that do not specify an explicit value for this requirement. Fractions of a core (for example 0.1) are supported on some batch systems, namely Mesos and singleMachine. Default is 1.0 --defaultDisk INT The default amount of disk space to dedicate a job. Only applicable to jobs that do not specify an explicit value for this requirement. Standard suffixes like K, Ki, M, Mi, G or Gi are supported. Default is 2.0G --defaultPreemptable BOOL Set if jobs that do not specifically prohibit it should able to run on preemptable (spot) nodes. --maxCores INT The maximum number of CPU cores to request from the batch system at any one time. Standard suffixes like K, Ki, M, Mi, G or Gi are supported. --maxMemory INT The maximum amount of memory to request from the batch system at any one time. Standard suffixes like K, Ki, M, Mi, G or Gi are supported. --maxDisk INT The maximum amount of disk space to request from the batch system at any one time. Standard suffixes like K, Ki, M, Mi, G or Gi are supported. --retryCount RETRYCOUNT Number of times to retry a failing job before giving up and labeling job failed. default=1 --doubleMem If set, batch jobs which die due to reaching memory limit on batch schedulers will have their memory doubled and they will be retried. The remaining retry count will be reduced by 1. Currently only supported by LSF. default=False. --maxJobDuration MAXJOBDURATION Maximum runtime of a job (in seconds) before we kill it (this is a lower bound, and the actual time before killing the job may be longer). --rescueJobsFrequency RESCUEJOBSFREQUENCY Period of time to wait (in seconds) between checking for missing/overlong jobs, that is jobs which get lost by the batch system. --maxServiceJobs MAXSERVICEJOBS The maximum number of service jobs that can be run concurrently, excluding service jobs running on preemptable nodes. default=9223372036854775807 --maxPreemptableServiceJobs MAXPREEMPTABLESERVICEJOBS The maximum number of service jobs that can run concurrently on preemptable nodes. default=9223372036854775807 --deadlockWait DEADLOCKWAIT Time, in seconds, to tolerate the workflow running only the same service jobs, with no jobs to use them, before declaring the workflow to be deadlocked and stopping. default=60 --deadlockCheckInterval DEADLOCKCHECKINTERVAL Time, in seconds, to wait between checks to see if the workflow is stuck running only service jobs, with no jobs to use them. Should be shorter than --deadlockWait. May need to be increased if the batch system cannot enumerate running jobs quickly enough, or if polling for running jobs is placing an unacceptable load on a shared cluster. default=30 --statePollingWait STATEPOLLINGWAIT Time, in seconds, to wait before doing a scheduler query for job state. Return cached results if within the waiting period. Only works for grid engine batch systems such as gridengine, htcondor, torque, slurm, and lsf. Miscellaneous Options --disableCaching Disables caching in the file store. This flag must be set to use a batch system that does not support cleanup, such as Parasol. --disableChaining Disables chaining of jobs (chaining uses one job's resource allocation for its successor job if possible). --maxLogFileSize MAXLOGFILESIZE The maximum size of a job log file to keep (in bytes), log files larger than this will be truncated to the last X bytes. Setting this option to zero will prevent any truncation. Setting this option to a negative value will truncate from the beginning. Default=62.5 K --writeLogs FILEPATH Write worker logs received by the leader into their own files at the specified path. Any non-empty standard output and error from failed batch system jobs will also be written into files at this path. The current working directory will be used if a path is not specified explicitly. Note: By default only the logs of failed jobs are returned to leader. Set log level to 'debug' to get logs back from successful jobs, and adjust 'maxLogFileSize' to control the truncation limit for worker logs. --writeLogsGzip FILEPATH Identical to -\-writeLogs except the logs files are gzipped on the leader. --realTimeLogging Enable real-time logging from workers to leader. --sseKey SSEKEY Path to file containing 32 character key to be used for server-side encryption on awsJobStore or googleJobStore. SSE will not be used if this flag is not passed. --setEnv NAME NAME=VALUE or NAME, -e NAME=VALUE or NAME are also valid. Set an environment variable early on in the worker. If VALUE is omitted, it will be looked up in the current environment. Independently of this option, the worker will try to emulate the leader's environment before running a job. Using this option, a variable can be injected into the worker process itself before it is started. --servicePollingInterval SERVICEPOLLINGINTERVAL Interval of time service jobs wait between polling for the existence of the keep-alive flag (default=60) --debugWorker Experimental no forking mode for local debugging. Specifically, workers are not forked and stderr/stdout are not redirected to the log. (default=False) --statusWait INT Seconds to wait between reports of running jobs. (default=3600) --disableProgress Disables the progress bar shown when standard error is a terminal. Restart Option In the event of failure, Toil can resume the pipeline by adding the argument --restart and rerunning the python script. Toil pipelines can even be edited and resumed which is useful for development or troubleshooting. Running Workflows with Services Toil supports jobs, or clusters of jobs, that run as services to other accessor jobs. Example services include server databases or Apache Spark Clusters. As service jobs exist to provide services to accessor jobs their runtime is dependent on the concurrent running of their accessor jobs. The dependencies between services and their accessor jobs can create potential deadlock scenarios, where the running of the workflow hangs because only service jobs are being run and their accessor jobs can not be scheduled because of too limited resources to run both simultaneously. To cope with this situation Toil attempts to schedule services and accessors intelligently, however to avoid a deadlock with workflows running service jobs it is advisable to use the following parameters: · --maxServiceJobs: The maximum number of service jobs that can be run concurrently, excluding service jobs running on preemptable nodes. · --maxPreemptableServiceJobs: The maximum number of service jobs that can run concurrently on preemptable nodes. Specifying these parameters so that at a maximum cluster size there will be sufficient resources to run accessors in addition to services will ensure that such a deadlock can not occur. If too low a limit is specified then a deadlock can occur in which toil can not schedule sufficient service jobs concurrently to complete the workflow. Toil will detect this situation if it occurs and throw a toil.DeadlockException exception. Increasing the cluster size and these limits will resolve the issue. Setting Options directly with the Toil Script It's good to remember that commandline options can be overridden in the Toil script itself. For example, toil.job.Job.Runner.getDefaultOptions() can be used to run toil with all default options, and in this example, it will override commandline args to run the default options and always run with the "./toilWorkflow" directory specified as the jobstore: options = Job.Runner.getDefaultOptions("./toilWorkflow") # Get the options object with Toil(options) as toil: toil.start(Job()) # Run the script However, each option can be explicitly set within the script by supplying arguments (in this example, we are setting logLevel = "DEBUG" (all log statements are shown) and clean="ALWAYS" (always delete the jobstore) like so: options = Job.Runner.getDefaultOptions("./toilWorkflow") # Get the options object options.logLevel = "DEBUG" # Set the log level to the debug level. options.clean = "ALWAYS" # Always delete the jobStore after a run with Toil(options) as toil: toil.start(Job()) # Run the script However, the usual incantation is to accept commandline args from the user with the following: parser = Job.Runner.getDefaultArgumentParser() # Get the parser options = parser.parse_args() # Parse user args to create the options object with Toil(options) as toil: toil.start(Job()) # Run the script Which can also, of course, then accept script supplied arguments as before (which will overwrite any user supplied args): parser = Job.Runner.getDefaultArgumentParser() # Get the parser options = parser.parse_args() # Parse user args to create the options object options.logLevel = "DEBUG" # Set the log level to the debug level. options.clean = "ALWAYS" # Always delete the jobStore after a run with Toil(options) as toil: toil.start(Job()) # Run the script
TOIL DEBUGGING
Toil has a number of tools to assist in debugging. Here we provide help in working through potential problems that a user might encounter in attempting to run a workflow. Introspecting the Jobstore Note: Currently these features are only implemented for use locally (single machine) with the fileJobStore. To view what files currently reside in the jobstore, run the following command: $ toil debug-file file:path-to-jobstore-directory \ --listFilesInJobStore When run from the commandline, this should generate a file containing the contents of the job store (in addition to displaying a series of log messages to the terminal). This file is named "jobstore_files.txt" by default and will be generated in the current working directory. If one wishes to copy any of these files to a local directory, one can run for example: $ toil debug-file file:path-to-jobstore \ --fetch overview.txt *.bam *.fastq \ --localFilePath=/home/user/localpath To fetch overview.txt, and all .bam and .fastq files. This can be used to recover previously used input and output files for debugging or reuse in other workflows, or use in general debugging to ensure that certain outputs were imported into the jobStore. Stats and Status See cli_status for more about gathering statistics about job success, runtime, and resource usage from workflows. Using a Python debugger If you execute a workflow using the --debugWorker flag, Toil will not fork in order to run jobs, which means you can either use pdb, or an IDE that supports debugging Python as you would normally. Note that the --debugWorker flag will only work with the singleMachine batch system (the default), and not any of the custom job schedulers.
RUNNING IN THE CLOUD
Toil supports Amazon Web Services (AWS) and Google Compute Engine (GCE) in the cloud and has autoscaling capabilities that can adapt to the size of your workflow, whether your workflow requires 10 instances or 20,000. Toil does this by creating a virtual cluster with Apache Mesos. Apache Mesos requires a leader node to coordinate the workflow, and worker nodes to execute the various tasks within the workflow. As the workflow runs, Toil will "autoscale", creating and terminating workers as needed to meet the demands of the workflow. Once a user is familiar with the basics of running toil locally (specifying a jobStore, and how to write a toil script), they can move on to the guides below to learn how to translate these workflows into cloud ready workflows. Managing a Cluster of Virtual Machines (Provisioning) Toil can launch and manage a cluster of virtual machines to run using the provisioner to run a workflow distributed over several nodes. The provisioner also has the ability to automatically scale up or down the size of the cluster to handle dynamic changes in computational demand (autoscaling). Currently we have working provisioners with AWS and GCE (Azure support has been deprecated). Toil uses Apache Mesos as the batchSystemOverview. See here for instructions for runningAWS. See here for instructions for runningGCE. Storage (Toil jobStore) Toil can make use of cloud storage such as AWS or Google buckets to take care of storage needs. This is useful when running Toil in single machine mode on any cloud platform since it allows you to make use of their integrated storage systems. For an overview of the job store see jobStoreOverview. For instructions configuring a particular job store see: · awsJobStore · googleJobStore
CLOUD PLATFORMS
Running on Kubernetes Kubernetes is a very popular container orchestration tool that has become a de facto cross-cloud-provider API for accessing cloud resources. Major cloud providers like Amazon, Microsoft, Kubernetes owner Google, and DigitalOcean have invested heavily in making Kubernetes work well on their platforms, by writing their own deployment documentation and developing provider-managed Kubernetes-based products. Using minikube, Kubernetes can even be run on a single machine. Toil supports running Toil workflows against a Kubernetes cluster, either in the cloud or deployed on user-owned hardware. Preparing your Kubernetes environment 1. Get a Kubernetes cluster To run Toil workflows on Kubernetes, you need to have a Kubernetes cluster set up. This will not be covered here, but there are many options available, and which one you choose will depend on which cloud ecosystem if any you use already, and on pricing. If you are just following along with the documentation, use minikube on your local machine. Note that currently the only way to run a Toil workflow on Kubernetes is to use the AWS Job Store, so your Kubernetes workflow will currently have to store its data in Amazon's cloud regardless of where you run it. This can result in significant egress charges from Amazon if you run it outside of Amazon. Kubernetes Cluster Providers: · Your own institution · Amazon EKS · Microsoft Azure AKS · Google GKE · DigitalOcean Kubernetes · minikube 2. Get a Kubernetes context on your local machine There are two main ways to run Toil workflows on Kubernetes. You can either run the Toil leader on a machine outside the cluster, with jobs submitted to and run on the cluster, or you can submit the Toil leader itself as a job and have it run inside the cluster. Either way, you will need to configure your own machine to be able to submit jobs to the Kubernetes cluster. Generally, this involves creating and populating a file named .kube/config in your user's home directory, and specifying the cluster to connect to, the certificate and token information needed for mutual authentication, and the Kubernetes namespace within which to work. However, Kubernetes configuration can also be picked up from other files in the .kube directory, environment variables, and the enclosing host when running inside a Kubernetes-managed container. You will have to do different things here depending on where you got your Kubernetes cluster: · Configuring for Amazon EKS · Configuring for Microsoft Azure AKS · Configuring for Google GKE · Configuring for DigitalOcean Kubernetes Clusters · Configuring for minikube Toil's internal Kubernetes configuration logic mirrors that of the kubectl command. Toil workflows will use the current kubectl context to launch their Kubernetes jobs. 3. If running the Toil leader in the cluster, get a service account If you are going to run your workflow's leader within the Kubernetes cluster (see Option 1: Running the Leader Inside Kubernetes), you will need a service account in your chosen Kubernetes namespace. Most namespaces should have a service account named default which should work fine. If your cluster requires you to use a different service account, you will need to obtain its name and use it when launching the Kubernetes job containing the Toil leader. 4. Set up appropriate permissions Your local Kubernetes context and/or the service account you are using to run the leader in the cluster will need to have certain permissions in order to run the workflow. Toil needs to be able to interact with jobs and pods in the cluster, and to retrieve pod logs. You as a user may need permission to set up an AWS credentials secret, if one is not already available. Additionally, it is very useful for you as a user to have permission to interact with nodes, and to shell into pods. The appropriate permissions may already be available to you and your service account by default, especially in managed or ease-of-use-optimized setups such as EKS or minikube. However, if the appropriate permissions are not already available, you or your cluster administrator will have to grant them manually. The following Role (toil-user) and ClusterRole (node-reader), to be applied with kubectl apply -f filename.yaml, should grant sufficient permissions to run Toil workflows when bound to your account and the service account used by Toil workflows. Be sure to replace YOUR_NAMESPACE_HERE with the namespace you are running your workflows in apiVersion: rbac.authorization.k8s.io/v1 kind: Role metadata: namespace: YOUR_NAMESPACE_HERE name: toil-user rules: - apiGroups: ["*"] resources: ["*"] verbs: ["explain", "get", "watch", "list", "describe", "logs", "attach", "exec", "port-forward", "proxy", "cp", "auth"] - apiGroups: ["batch"] resources: ["*"] verbs: ["get", "watch", "list", "create", "run", "set", "delete"] - apiGroups: [""] resources: ["secrets", "pods", "pods/attach", "podtemplates", "configmaps", "events", "services"] verbs: ["patch", "get", "update", "watch", "list", "create", "run", "set", "delete", "exec"] - apiGroups: [""] resources: ["pods", "pods/log"] verbs: ["get", "list"] - apiGroups: [""] resources: ["pods/exec"] verbs: ["create"] apiVersion: rbac.authorization.k8s.io/v1 kind: ClusterRole metadata: name: node-reader rules: - apiGroups: [""] resources: ["nodes"] verbs: ["get", "list", "describe"] - apiGroups: [""] resources: ["namespaces"] verbs: ["get", "list", "describe"] - apiGroups: ["metrics.k8s.io"] resources: ["*"] verbs: ["*"] To bind a user or service account to the Role or ClusterRole and actually grant the permissions, you will need a RoleBinding and a ClusterRoleBinding, respectively. Make sure to fill in the namespace, username, and service account name, and add more user stanzas if your cluster is to support multiple Toil users. apiVersion: rbac.authorization.k8s.io/v1 kind: RoleBinding metadata: name: toil-developer-member namespace: toil subjects: - kind: User name: YOUR_KUBERNETES_USERNAME_HERE apiGroup: rbac.authorization.k8s.io - kind: ServiceAccount name: YOUR_SERVICE_ACCOUNT_NAME_HERE namespace: YOUR_NAMESPACE_HERE roleRef: kind: Role name: toil-user apiGroup: rbac.authorization.k8s.io apiVersion: rbac.authorization.k8s.io/v1 kind: ClusterRoleBinding metadata: name: read-nodes subjects: - kind: User name: YOUR_KUBERNETES_USERNAME_HERE apiGroup: rbac.authorization.k8s.io - kind: ServiceAccount name: YOUR_SERVICE_ACCOUNT_NAME_HERE namespace: YOUR_NAMESPACE_HERE roleRef: kind: ClusterRole name: node-reader apiGroup: rbac.authorization.k8s.io AWS Job Store for Kubernetes Currently, the only job store, which is what Toil uses to exchange data between jobs, that works with jobs running on Kubernetes is the AWS Job Store. This requires that the Toil leader and Kubernetes jobs be able to connect to and use Amazon S3 and Amazon SimpleDB. It also requires that you have an Amazon Web Services account. 1. Get access to AWS S3 and SimpleDB In your AWS account, you need to create an AWS access key. First go to the IAM dashboard; for "us-west1", the link would be: https://console.aws.amazon.com/iam/home?region=us-west-1#/home Then create an access key, and save the Access Key ID and the Secret Key. As documented in the AWS documentation: 1. On the IAM Dashboard page, choose your account name in the navigation bar, and then choose My Security Credentials. 2. Expand the Access keys (access key ID and secret access key) section. 3. Choose Create New Access Key. Then choose Download Key File to save the access key ID and secret access key to a file on your computer. After you close the dialog box, you can't retrieve this secret access key again. Make sure that, if your AWS infrastructure requires your user to authenticate with a multi-factor authentication (MFA) token, you obtain a second secret key and access key that don't have this requirement. The secret key and access key used to populate the Kubernetes secret that allows the jobs to contact the job store need to be usable without human intervention. 2. Configure AWS access from the local machine This only really needs to happen if you run the leader on the local machine. But we need the files in place to fill in the secret in the next step. Run: $ aws configure Then when prompted, enter your secret key and access key. This should create a file ~/.aws/credentials that looks like this: [default] aws_access_key_id = BLAH aws_secret_access_key = blahblahblah 3. Create a Kubernetes secret to give jobs access to AWS Go into the directory where the credentials file is: $ cd ~/.aws Then, create a Kubernetes secret that contains it. We'll call it aws-credentials: $ kubectl create secret generic aws-credentials --from-file credentials Configuring Toil for your Kubernetes environment To configure your workflow to run on Kubernetes, you will have to configure several environment variables, in addition to passing the --batchSystem kubernetes option. Doing the research to figure out what values to give these variables may require talking to your cluster provider. 1. TOIL_AWS_SECRET_NAME is the most important, and must be set to the secret that contains your AWS credentials file, if your cluster nodes don't otherwise have access to S3 and SimpleDB (such as through IAM roles). This is required for the AWS job store to work, which is currently the only job store that can be used on Kubernetes. In this example we are using aws-credentials. 2. TOIL_KUBERNETES_HOST_PATH can be set to allow Toil jobs on the same physical host to share a cache. It should be set to a path on the host where the shared cache should be stored. It will be mounted as /var/lib/toil, or at TOIL_WORKDIR if specified, inside the container. This path must already exist on the host, and must have as much free space as your Kubernetes node offers to jobs. In this example, we are using /data/scratch. To actually make use of caching, make sure not to use --disableCaching. 3. TOIL_KUBERNETES_OWNER should be set to the username of the user running the Toil workflow. The jobs that Toil creates will include this username, so they can be more easily recognized, and cleaned up by the user if anything happens to the Toil leader. In this example we are using demo-user. Note that Docker containers cannot be run inside of unprivileged Kubernetes pods (which are themselves containers). The Docker daemon does not (yet) support this. Other tools, such as Singularity in its user-namespace mode, are able to run containers from within containers. If using Singularity to run containerized tools, and you want downloaded container images to persist between Toil jobs, you will also want to set TOIL_KUBERNETES_HOST_PATH and make sure that Singularity is downloading its containers under the Toil work directory (/var/lib/toil buy default) by setting SINGULARITY_CACHEDIR. However, you will need to make sure that no two jobs try to download the same container at the same time; Singularity has no synchronization or locking around its cache, but the cache is also not safe for simultaneous access by multiple Singularity invocations. Some Toil workflows use their own custom workaround logic for this problem; this work is likely to be made part of Toil in a future release. Running workflows To run the workflow, you will need to run the Toil leader process somewhere. It can either be run inside Kubernetes as a Kubernetes job, or outside Kubernetes as a normal command. Option 1: Running the Leader Inside Kubernetes Once you have determined a set of environment variable values for your workflow run, write a YAML file that defines a Kubernetes job to run your workflow with that configuration. Some configuration items (such as your username, and the name of your AWS credentials secret) need to be written into the YAML so that they can be used from the leader as well. Note that the leader pod will need your workflow script, its other dependencies, and Toil all installed. An easy way to get Toil installed is to start with the Toil appliance image for the version of Toil you want to use. In this example, we use quay.io/ucsc_cgl/toil:5.5.0. Here's an example YAML file to run a test workflow: apiVersion: batch/v1 kind: Job metadata: # It is good practice to include your username in your job name. # Also specify it in TOIL_KUBERNETES_OWNER name: demo-user-toil-test # Do not try and rerun the leader job if it fails spec: backoffLimit: 0 template: spec: # Do not restart the pod when the job fails, but keep it around so the # log can be retrieved restartPolicy: Never volumes: - name: aws-credentials-vol secret: # Make sure the AWS credentials are available as a volume. # This should match TOIL_AWS_SECRET_NAME secretName: aws-credentials # You may need to replace this with a different service account name as # appropriate for your cluster. serviceAccountName: default containers: - name: main image: quay.io/ucsc_cgl/toil:5.5.0 env: # Specify your username for inclusion in job names - name: TOIL_KUBERNETES_OWNER value: demo-user # Specify where to find the AWS credentials to access the job store with - name: TOIL_AWS_SECRET_NAME value: aws-credentials # Specify where per-host caches should be stored, on the Kubernetes hosts. # Needs to be set for Toil's caching to be efficient. - name: TOIL_KUBERNETES_HOST_PATH value: /data/scratch volumeMounts: # Mount the AWS credentials volume - mountPath: /root/.aws name: aws-credentials-vol resources: # Make sure to set these resource limits to values large enough # to accommodate the work your workflow does in the leader # process, but small enough to fit on your cluster. # # Since no request values are specified, the limits are also used # for the requests. limits: cpu: 2 memory: "4Gi" ephemeral-storage: "10Gi" command: - /bin/bash - -c - | # This Bash script will set up Toil and the workflow to run, and run them. set -e # We make sure to create a work directory; Toil can't hot-deploy a # script from the root of the filesystem, which is where we start. mkdir /tmp/work cd /tmp/work # We make a virtual environment to allow workflow dependencies to be # hot-deployed. # # We don't really make use of it in this example, but for workflows # that depend on PyPI packages we will need this. # # We use --system-site-packages so that the Toil installed in the # appliance image is still available. virtualenv --python python3 --system-site-packages venv . venv/bin/activate # Now we install the workflow. Here we're using a demo workflow # script from Toil itself. wget https://raw.githubusercontent.com/DataBiosphere/toil/releases/4.1.0/src/toil/test/docs/scripts/tutorial_helloworld.py # Now we run the workflow. We make sure to use the Kubernetes batch # system and an AWS job store, and we set some generally useful # logging options. We also make sure to enable caching. python3 tutorial_helloworld.py \ aws:us-west-2:demouser-toil-test-jobstore \ --batchSystem kubernetes \ --realTimeLogging \ --logInfo You can save this YAML as leader.yaml, and then run it on your Kubernetes installation with: $ kubectl apply -f leader.yaml To monitor the progress of the leader job, you will want to read its logs. If you are using a Kubernetes dashboard such as k9s, you can simply find the pod created for the job in the dashboard, and view its logs there. If not, you will need to locate the pod by hand. Monitoring and Debugging Kubernetes Jobs and Pods The following techniques are most useful for looking at the pod which holds the Toil leader, but they can also be applied to individual Toil jobs on Kubernetes, even when the leader is outside the cluster. Kubernetes names pods for jobs by appending a short random string to the name of the job. You can find the name of the pod for your job by doing: $ kubectl get pods | grep demo-user-toil-test demo-user-toil-test-g5496 1/1 Running 0 2m Assuming you have set TOIL_KUBERNETES_OWNER correctly, you should be able to find all of your workflow's pods by searching for your username: $ kubectl get pods | grep demo-user If the status of a pod is anything other than Pending, you will be able to view its logs with: $ kubectl logs demo-user-toil-test-g5496 This will dump the pod's logs from the beginning to now and terminate. To follow along with the logs from a running pod, add the -f option: $ kubectl logs -f demo-user-toil-test-g5496 A status of ImagePullBackoff suggests that you have requested to use an image that is not available. Check the image section of your YAML if you are looking at a leader, or the value of TOIL_APPLIANCE_SELF if you are delaying with a worker job. You also might want to check your Kubernetes node's Internet connectivity and DNS function; in Kubernetes, DNS depends on system-level pods which can be terminated or evicted in cases of resource oversubscription, just like user workloads. If your pod seems to be stuck Pending, ContainerCreating, you can get information on what is wrong with it by using kubectl describe pod: $ kubectl describe pod demo-user-toil-test-g5496 Pay particular attention to the Events: section at the end of the output. An indication that a job is too big for the available nodes on your cluster, or that your cluster is too busy for your jobs, is FailedScheduling events: Type Reason Age From Message ---- ------ ---- ---- ------- Warning FailedScheduling 13s (x79 over 100m) default-scheduler 0/4 nodes are available: 1 Insufficient cpu, 1 Insufficient ephemeral-storage, 4 Insufficient memory. If a pod is running but seems to be behaving erratically, or seems stuck, you can shell into it and look around: $ kubectl exec -ti demo-user-toil-test-g5496 /bin/bash One common cause of stuck pods is attempting to use more memory than allowed by Kubernetes (or by the Toil job's memory resource requirement), but in a way that does not trigger the Linux OOM killer to terminate the pod's processes. In these cases, the pod can remain stuck at nearly 100% memory usage more or less indefinitely, and attempting to shell into the pod (which needs to start a process within the pod, using some of its memory) will fail. In these cases, the recommended solution is to kill the offending pod and increase its (or its Toil job's) memory requirement, or reduce its memory needs by adapting user code. When Things Go Wrong The Toil Kubernetes batch system includes cleanup code to terminate worker jobs when the leader shuts down. However, if the leader pod is removed by Kubernetes, is forcibly killed or otherwise suffers a sudden existence failure, it can go away while its worker jobs live on. It is not recommended to restart a workflow in this state, as jobs from the previous invocation will remain running and will be trying to modify the job store concurrently with jobs from the new invocation. To clean up dangling jobs, you can use the following snippet: $ kubectl get jobs | grep demo-user | cut -f1 -d' ' | xargs -n10 kubectl delete job This will delete all jobs with demo-user's username in their names, in batches of 10. You can also use the UUID that Toil assigns to a particular workflow invocation in the filter, to clean up only the jobs pertaining to that workflow invocation. Option 2: Running the Leader Outside Kubernetes If you don't want to run your Toil leader inside Kubernetes, you can run it locally instead. This can be useful when developing a workflow; files can be hot-deployed from your local machine directly to Kubernetes. However, your local machine will have to have (ideally role-assumption- and MFA-free) access to AWS, and access to Kubernetes. Real time logging will not work unless your local machine is able to listen for incoming UDP packets on arbitrary ports on the address it uses to contact the IPv4 Internet; Toil does no NAT traversal or detection. Note that if you set TOIL_WORKDIR when running your workflow like this, it will need to be a directory that exists both on the host and in the Toil appliance. Here is an example of running our test workflow leader locally, outside of Kubernetes: $ export TOIL_KUBERNETES_OWNER=demo-user # This defaults to your local username if not set $ export TOIL_AWS_SECRET_NAME=aws-credentials $ export TOIL_KUBERNETES_HOST_PATH=/data/scratch $ virtualenv --python python3 --system-site-packages venv $ . venv/bin/activate $ wget https://raw.githubusercontent.com/DataBiosphere/toil/releases/4.1.0/src/toil/test/docs/scripts/tutorial_helloworld.py $ python3 tutorial_helloworld.py \ aws:us-west-2:demouser-toil-test-jobstore \ --batchSystem kubernetes \ --realTimeLogging \ --logInfo Running in AWS Toil jobs can be run on a variety of cloud platforms. Of these, Amazon Web Services (AWS) is currently the best-supported solution. Toil provides the clusterRef to conveniently create AWS clusters, connect to the leader of the cluster, and then launch a workflow. The leader handles distributing the jobs over the worker nodes and autoscaling to optimize costs. The Running a Workflow with Autoscaling section details how to create a cluster and run a workflow that will dynamically scale depending on the workflow's needs. The Static Provisioning section explains how a static cluster (one that won't automatically change in size) can be created and provisioned (grown, shrunk, destroyed, etc.). Preparing your AWS environment To use Amazon Web Services (AWS) to run Toil or to just use S3 to host the files during the computation of a workflow, first set up and configure an account with AWS: 1. If necessary, create and activate an AWS account 2. Next, generate a key pair for AWS with the command (do NOT generate your key pair with the Amazon browser): $ ssh-keygen -t rsa 3. This should prompt you to save your key. Please save it in ~/.ssh/id_rsa 4. Now move this to where your OS can see it as an authorized key: $ cat ~/.ssh/id_rsa.pub >> ~/.ssh/authorized_keys 5. Next, you'll need to add your key to the ssh-agent: $ eval `ssh-agent -s` $ ssh-add If your key has a passphrase, you will be prompted to enter it here once. 6. You'll also need to chmod your private key (good practice but also enforced by AWS): $ chmod 400 id_rsa 7. Now you'll need to add the key to AWS via the browser. For example, on us-west1, this address would accessible at: https://us-west-1.console.aws.amazon.com/ec2/v2/home?region=us-west-1#KeyPairs:sort=keyName 8. Now click on the "Import Key Pair" button to add your key: Adding an Amazon Key Pair.UNINDENT 9. Next, you need to create an AWS access key. First go to the IAM dashboard, again; for "us-west1", the example link would be here: https://console.aws.amazon.com/iam/home?region=us-west-1#/home 10. The directions (transcribed from: https://docs.aws.amazon.com/general/latest/gr/managing-aws-access-keys.html ) are now: 1. On the IAM Dashboard page, choose your account name in the navigation bar, and then choose My Security Credentials. 2. Expand the Access keys (access key ID and secret access key) section. 3. Choose Create New Access Key. Then choose Download Key File to save the access key ID and secret access key to a file on your computer. After you close the dialog box, you can't retrieve this secret access key again. 11. Now you should have a newly generated "AWS Access Key ID" and "AWS Secret Access Key". We can now install the AWS CLI and make sure that it has the proper credentials: $ pip install awscli --upgrade --user 12. Now configure your AWS credentials with: $ aws configure 13. Add your "AWS Access Key ID" and "AWS Secret Access Key" from earlier and your region and output format: " AWS Access Key ID [****************Q65Q]: " " AWS Secret Access Key [****************G0ys]: " " Default region name [us-west-1]: " " Default output format [json]: " This will create the files ~/.aws/config and ~/.aws/credentials. 14. If not done already, install toil (example uses version 5.3.0, but we recommend the latest release): $ virtualenv venv $ source venv/bin/activate $ pip install toil[all]==5.3.0 15. Now that toil is installed and you are running a virtualenv, an example of launching a toil leader node would be the following (again, note that we set TOIL_APPLIANCE_SELF to toil version 5.3.0 in this example, but please set the version to the installed version that you are using if you're using a different version): $ TOIL_APPLIANCE_SELF=quay.io/ucsc_cgl/toil:5.3.0 \ toil launch-cluster clustername \ --leaderNodeType t2.medium \ --zone us-west-1a \ --keyPairName id_rsa To further break down each of these commands: TOIL_APPLIANCE_SELF=quay.io/ucsc_cgl/toil:latest --- This is optional. It specifies a mesos docker image that we maintain with the latest version of toil installed on it. If you want to use a different version of toil, please specify the image tag you need from https://quay.io/repository/ucsc_cgl/toil?tag=latest&tab=tags. toil launch-cluster --- Base command in toil to launch a cluster. clustername --- Just choose a name for your cluster. --leaderNodeType t2.medium --- Specify the leader node type. Make a t2.medium (2CPU; 4Gb RAM; $0.0464/Hour). List of available AWS instances: https://aws.amazon.com/ec2/pricing/on-demand/ --zone us-west-1a --- Specify the AWS zone you want to launch the instance in. Must have the same prefix as the zone in your awscli credentials (which, in the example of this tutorial is: "us-west-1"). --keyPairName id_rsa --- The name of your key pair, which should be "id_rsa" if you've followed this tutorial. AWS Job Store Using the AWS job store is straightforward after you've finished Preparing your AWS environment; all you need to do is specify the prefix for the job store name. To run the sort example sort example with the AWS job store you would type $ python sort.py aws:us-west-2:my-aws-sort-jobstore Toil Provisioner The Toil provisioner is included in Toil alongside the [aws] extra and allows us to spin up a cluster. Getting started with the provisioner is simple: 1. Make sure you have Toil installed with the AWS extras. For detailed instructions see extras. 2. You will need an AWS account and you will need to save your AWS credentials on your local machine. For help setting up an AWS account see here. For setting up your AWS credentials follow instructions here. The Toil provisioner is built around the Toil Appliance, a Docker image that bundles Toil and all its requirements (e.g. Mesos). This makes deployment simple across platforms, and you can even simulate a cluster locally (see appliance_dev for details). Choosing Toil Appliance Image When using the Toil provisioner, the appliance image will be automatically chosen based on the pip-installed version of Toil on your system. That choice can be overridden by setting the environment variables TOIL_DOCKER_REGISTRY and TOIL_DOCKER_NAME or TOIL_APPLIANCE_SELF. See envars for more information on these variables. If you are developing with autoscaling and want to test and build your own appliance have a look at appliance_dev. For information on using the Toil Provisioner have a look at Running a Workflow with Autoscaling. Details about Launching a Cluster in AWS Using the provisioner to launch a Toil leader instance is simple using the launch-cluster command. For example, to launch a cluster named "my-cluster" with a t2.medium leader in the us-west-2a zone, run (venv) $ toil launch-cluster my-cluster \ --leaderNodeType t2.medium \ --zone us-west-2a \ --keyPairName <your-AWS-key-pair-name> The cluster name is used to uniquely identify your cluster and will be used to populate the instance's Name tag. Also, the Toil provisioner will automatically tag your cluster with an Owner tag that corresponds to your keypair name to facilitate cost tracking. In addition, the ToilNodeType tag can be used to filter "leader" vs. "worker" nodes in your cluster. The leaderNodeType is an EC2 instance type. This only affects the leader node. The --zone parameter specifies which EC2 availability zone to launch the cluster in. Alternatively, you can specify this option via the TOIL_AWS_ZONE environment variable. Note: the zone is different from an EC2 region. A region corresponds to a geographical area like us-west-2 (Oregon), and availability zones are partitions of this area like us-west-2a. By default, Toil creates an IAM role for each cluster with sufficient permissions to perform cluster operations (e.g. full S3, EC2, and SDB access). If the default permissions are not sufficient for your use case (e.g. if you need access to ECR), you may create a custom IAM role with all necessary permissions and set the --awsEc2ProfileArn parameter when launching the cluster. Note that your custom role must at least have these permissions in order for the Toil cluster to function properly. In addition, Toil creates a new security group with the same name as the cluster name with default rules (e.g. opens port 22 for SSH access). If you require additional security groups, you may use the --awsEc2ExtraSecurityGroupId parameter when launching the cluster. Note: Do not use the same name as the cluster name for the extra security groups as any security group matching the cluster name will be deleted once the cluster is destroyed. For more information on options try: (venv) $ toil launch-cluster --help Static Provisioning Toil can be used to manage a cluster in the cloud by using the clusterRef. The cluster utilities also make it easy to run a toil workflow directly on this cluster. We call this static provisioning because the size of the cluster does not change. This is in contrast with Running a Workflow with Autoscaling. To launch worker nodes alongside the leader we use the -w option: (venv) $ toil launch-cluster my-cluster \ --leaderNodeType t2.small -z us-west-2a \ --keyPairName your-AWS-key-pair-name \ --nodeTypes m3.large,t2.micro -w 1,4 This will spin up a leader node of type t2.small with five additional workers --- one m3.large instance and four t2.micro. Currently static provisioning is only possible during the cluster's creation. The ability to add new nodes and remove existing nodes via the native provisioner is in development. Of course the cluster can always be deleted with the destroyCluster utility. Uploading Workflows Now that our cluster is launched, we use the rsyncCluster utility to copy the workflow to the leader. For a simple workflow in a single file this might look like (venv) $ toil rsync-cluster -z us-west-2a my-cluster toil-workflow.py :/ NOTE: If your toil workflow has dependencies have a look at the autoDeploying section for a detailed explanation on how to include them. Running a Workflow with Autoscaling Autoscaling is a feature of running Toil in a cloud whereby additional cloud instances are launched to run the workflow. Autoscaling leverages Mesos containers to provide an execution environment for these workflows. NOTE: Make sure you've done the AWS setup in Preparing your AWS environment. 1. Download sort.py 2. Launch the leader node in AWS using the launchCluster command: (venv) $ toil launch-cluster <cluster-name> \ --keyPairName <AWS-key-pair-name> \ --leaderNodeType t2.medium \ --zone us-west-2a 3. Copy the sort.py script up to the leader node: (venv) $ toil rsync-cluster -z us-west-2a <cluster-name> sort.py :/root 4. Login to the leader node: (venv) $ toil ssh-cluster -z us-west-2a <cluster-name> 5. Run the script as an autoscaling workflow: $ python /root/sort.py aws:us-west-2:<my-jobstore-name> \ --provisioner aws \ --nodeTypes c3.large \ --maxNodes 2 \ --batchSystem mesos NOTE: In this example, the autoscaling Toil code creates up to two instances of type c3.large and launches Mesos slave containers inside them. The containers are then available to run jobs defined by the sort.py script. Toil also creates a bucket in S3 called aws:us-west-2:autoscaling-sort-jobstore to store intermediate job results. The Toil autoscaler can also provision multiple different node types, which is useful for workflows that have jobs with varying resource requirements. For example, one could execute the script with --nodeTypes c3.large,r3.xlarge --maxNodes 5,1, which would allow the provisioner to create up to five c3.large nodes and one r3.xlarge node for memory-intensive jobs. In this situation, the autoscaler would avoid creating the more expensive r3.xlarge node until needed, running most jobs on the c3.large nodes. 1. View the generated file to sort: $ head fileToSort.txt 2. View the sorted file: $ head sortedFile.txt For more information on other autoscaling (and other) options have a look at workflowOptions and/or run $ python my-toil-script.py --help IMPORTANT: Some important caveats about starting a toil run through an ssh session are explained in the sshCluster section. Preemptability Toil can run on a heterogeneous cluster of both preemptable and non-preemptable nodes. Being preemptable node simply means that the node may be shut down at any time, while jobs are running. These jobs can then be restarted later somewhere else. A node type can be specified as preemptable by adding a spot bid to its entry in the list of node types provided with the --nodeTypes flag. If spot instance prices rise above your bid, the preemptable node whill be shut down. While individual jobs can each explicitly specify whether or not they should be run on preemptable nodes via the boolean preemptable resource requirement, the --defaultPreemptable flag will allow jobs without a preemptable requirement to run on preemptable machines. Specify Preemptability Carefully Ensure that your choices for --nodeTypes and --maxNodes <> make sense for your workflow and won't cause it to hang. You should make sure the provisioner is able to create nodes large enough to run the largest job in the workflow, and that non-preemptable node types are allowed if there are non-preemptable jobs in the workflow. Finally, the --preemptableCompensation flag can be used to handle cases where preemptable nodes may not be available but are required for your workflow. With this flag enabled, the autoscaler will attempt to compensate for a shortage of preemptable nodes of a certain type by creating non-preemptable nodes of that type, if non-preemptable nodes of that type were specified in --nodeTypes. Using MinIO and S3-Compatible object stores Toil can be configured to access files stored in an S3-compatible object store such as MinIO. The following environment variables can be used to configure the S3 connection used: · TOIL_S3_HOST: the IP address or hostname to use for connecting to S3 · TOIL_S3_PORT: the port number to use for connecting to S3, if needed · TOIL_S3_USE_SSL: enable or disable the usage of SSL for connecting to S3 (True by default) Examples: TOIL_S3_HOST=127.0.0.1 TOIL_S3_PORT=9010 TOIL_S3_USE_SSL=False Dashboard Toil provides a dashboard for viewing the RAM and CPU usage of each node, the number of issued jobs of each type, the number of failed jobs, and the size of the jobs queue. To launch this dashboard for a toil workflow, include the --metrics flag in the toil script command. The dashboard can then be viewed in your browser at localhost:3000 while connected to the leader node through toil ssh-cluster: To change the default port number, you can use the --grafana_port argument: (venv) $ toil ssh-cluster -z us-west-2a --grafana_port 8000 <cluster-name> On AWS, the dashboard keeps track of every node in the cluster to monitor CPU and RAM usage, but it can also be used while running a workflow on a single machine. The dashboard uses Grafana as the front end for displaying real-time plots, and Prometheus for tracking metrics exported by toil: [image] In order to use the dashboard for a non-released toil version, you will have to build the containers locally with make docker, since the prometheus, grafana, and mtail containers used in the dashboard are tied to a specific toil version. Running in Google Compute Engine (GCE) Toil supports a provisioner with Google, and a Google Job Store. To get started, follow instructions for Preparing your Google environment. Preparing your Google environment Toil supports using the Google Cloud Platform. Setting this up is easy! 1. Make sure that the google extra (extras) is installed 2. Follow Google's Instructions to download credentials and set the GOOGLE_APPLICATION_CREDENTIALS environment variable 3. Create a new ssh key with the proper format. To create a new ssh key run the command $ ssh-keygen -t rsa -f ~/.ssh/id_rsa -C [USERNAME] where [USERNAME] is something like jane@example.com. Make sure to leave your password blank. WARNING: This command could overwrite an old ssh key you may be using. If you have an existing ssh key you would like to use, it will need to be called id_rsa and it needs to have no password set. Make sure only you can read the SSH keys: $ chmod 400 ~/.ssh/id_rsa ~/.ssh/id_rsa.pub 4. Add your newly formatted public key to Google. To do this, log into your Google Cloud account and go to metadata section under the Compute tab. [image] Near the top of the screen click on 'SSH Keys', then edit, add item, and paste the key. Then save: [image] For more details look at Google's instructions for adding SSH keys. Google Job Store To use the Google Job Store you will need to set the GOOGLE_APPLICATION_CREDENTIALS environment variable by following Google's instructions. Then to run the sort example with the Google job store you would type $ python sort.py google:my-project-id:my-google-sort-jobstore Running a Workflow with Autoscaling WARNING: Google Autoscaling is in beta! The steps to run a GCE workflow are similar to those of AWS (Autoscaling), except you will need to explicitly specify the --provisioner gce option which otherwise defaults to aws. 1. Download sort.py 2. Launch the leader node in GCE using the launchCluster command: (venv) $ toil launch-cluster <CLUSTER-NAME> \ --provisioner gce \ --leaderNodeType n1-standard-1 \ --keyPairName <SSH-KEYNAME> \ --zone us-west1-a Where <SSH-KEYNAME> is the first part of [USERNAME] used when setting up your ssh key. For example if [USERNAME] was jane@example.com, <SSH-KEYNAME> should be jane. The --keyPairName option is for an SSH key that was added to the Google account. If your ssh key [USERNAME] was jane@example.com, then your key pair name will be just jane. 3. Upload the sort example and ssh into the leader: (venv) $ toil rsync-cluster --provisioner gce <CLUSTER-NAME> sort.py :/root (venv) $ toil ssh-cluster --provisioner gce <CLUSTER-NAME> 4. Run the workflow: $ python /root/sort.py google:<PROJECT-ID>:<JOBSTORE-NAME> \ --provisioner gce \ --batchSystem mesos \ --nodeTypes n1-standard-2 \ --maxNodes 2 5. Clean up: $ exit # this exits the ssh from the leader node (venv) $ toil destroy-cluster --provisioner gce <CLUSTER-NAME> Cluster Utilities There are several utilities used for starting and managing a Toil cluster using the AWS provisioner. They are installed via the [aws] or [google] extra. For installation details see installProvisioner. The cluster utilities are used for runningAWS and are comprised of toil launch-cluster, toil rsync-cluster, toil ssh-cluster, and toil destroy-cluster entry points. Cluster commands specific to toil are: status --- Reports runtime and resource usage for all jobs in a specified jobstore (workflow must have originally been run using the -\-stats option). stats --- Inspects a job store to see which jobs have failed, run successfully, etc. destroy-cluster --- For autoscaling. Terminates the specified cluster and associated resources. launch-cluster --- For autoscaling. This is used to launch a toil leader instance with the specified provisioner. rsync-cluster --- For autoscaling. Used to transfer files to a cluster launched with toil launch-cluster. ssh-cluster --- SSHs into the toil appliance container running on the leader of the cluster. clean --- Delete the job store used by a previous Toil workflow invocation. kill --- Kills any running jobs in a rogue toil. For information on a specific utility run: toil launch-cluster --help for a full list of its options and functionality. The cluster utilities can be used for runningGCE and runningAWS. TIP: By default, all of the cluster utilities expect to be running on AWS. To run with Google you will need to specify the --provisioner gce option for each utility. NOTE: Boto must be configured with AWS credentials before using cluster utilities. runningGCE contains instructions for Stats Command To use the stats command, a workflow must first be run using the --stats option. Using this command makes certain that toil does not delete the job store, no matter what other options are specified (i.e. normally the option --clean=always would delete the job, but --stats will override this). An example of this would be running the following: python discoverfiles.py file:my-jobstore --stats Where discoverfiles.py is the following: import os import subprocess from toil.common import Toil from toil.job import Job class discoverFiles(Job): """Views files at a specified path using ls.""" def __init__(self, path, *args, **kwargs): self.path = path super().__init__(*args, **kwargs) def run(self, fileStore): if os.path.exists(self.path): subprocess.check_call(["ls", self.path]) def main(): options = Job.Runner.getDefaultArgumentParser().parse_args() options.clean = "always" job1 = discoverFiles(path="/sys/", displayName='sysFiles') job2 = discoverFiles(path=os.path.expanduser("~"), displayName='userFiles') job3 = discoverFiles(path="/tmp/") job1.addChild(job2) job2.addChild(job3) with Toil(options) as toil: if not toil.options.restart: toil.start(job1) else: toil.restart() if __name__ == '__main__': main() Notice the displayName key, which can rename a job, giving it an alias when it is finally displayed in stats. Running this workflow file should record three job names: sysFiles (job1), userFiles (job2), and discoverFiles (job3). To see the runtime and resources used for each job when it was run, type toil stats file:my-jobstore This should output the following: Batch System: singleMachine Default Cores: 1 Default Memory: 2097152K Max Cores: 9.22337e+18 Total Clock: 0.56 Total Runtime: 1.01 Worker Count | Time* | Clock | Wait | Memory n | min med* ave max total | min med ave max total | min med ave max total | min med ave max total 1 | 0.14 0.14 0.14 0.14 0.14 | 0.13 0.13 0.13 0.13 0.13 | 0.01 0.01 0.01 0.01 0.01 | 76K 76K 76K 76K 76K Job Worker Jobs | min med ave max | 3 3 3 3 Count | Time* | Clock | Wait | Memory n | min med* ave max total | min med ave max total | min med ave max total | min med ave max total 3 | 0.01 0.06 0.05 0.07 0.14 | 0.00 0.06 0.04 0.07 0.12 | 0.00 0.01 0.00 0.01 0.01 | 76K 76K 76K 76K 229K sysFiles Count | Time* | Clock | Wait | Memory n | min med* ave max total | min med ave max total | min med ave max total | min med ave max total 1 | 0.01 0.01 0.01 0.01 0.01 | 0.00 0.00 0.00 0.00 0.00 | 0.01 0.01 0.01 0.01 0.01 | 76K 76K 76K 76K 76K userFiles Count | Time* | Clock | Wait | Memory n | min med* ave max total | min med ave max total | min med ave max total | min med ave max total 1 | 0.06 0.06 0.06 0.06 0.06 | 0.06 0.06 0.06 0.06 0.06 | 0.01 0.01 0.01 0.01 0.01 | 76K 76K 76K 76K 76K discoverFiles Count | Time* | Clock | Wait | Memory n | min med* ave max total | min med ave max total | min med ave max total | min med ave max total 1 | 0.07 0.07 0.07 0.07 0.07 | 0.07 0.07 0.07 0.07 0.07 | 0.00 0.00 0.00 0.00 0.00 | 76K 76K 76K 76K 76K Once we're done, we can clean up the job store by running toil clean file:my-jobstore Status Command Continuing the example from the stats section above, if we ran our workflow with the command python discoverfiles.py file:my-jobstore --stats We could interrogate our jobstore with the status command, for example: toil status file:my-jobstore If the run was successful, this would not return much valuable information, something like 2018-01-11 19:31:29,739 - toil.lib.bioio - INFO - Root logger is at level 'INFO', 'toil' logger at level 'INFO'. 2018-01-11 19:31:29,740 - toil.utils.toilStatus - INFO - Parsed arguments 2018-01-11 19:31:29,740 - toil.utils.toilStatus - INFO - Checking if we have files for Toil The root job of the job store is absent, the workflow completed successfully. Otherwise, the status command should return the following: There are x unfinished jobs, y parent jobs with children, z jobs with services, a services, and b totally failed jobs currently in c. Clean Command If a Toil pipeline didn't finish successfully, or was run using --clean=always or --stats, the job store will exist until it is deleted. toil clean <jobStore> ensures that all artifacts associated with a job store are removed. This is particularly useful for deleting AWS job stores, which reserves an SDB domain as well as an S3 bucket. The deletion of the job store can be modified by the --clean argument, and may be set to always, onError, never, or onSuccess (default). Temporary directories where jobs are running can also be saved from deletion using the --cleanWorkDir, which has the same options as --clean. This option should only be run when debugging, as intermediate jobs will fill up disk space. Launch-Cluster Command Running toil launch-cluster starts up a leader for a cluster. Workers can be added to the initial cluster by specifying the -w option. An example would be $ toil launch-cluster my-cluster \ --leaderNodeType t2.small -z us-west-2a \ --keyPairName your-AWS-key-pair-name \ --nodeTypes m3.large,t2.micro -w 1,4 Options are listed below. These can also be displayed by running $ toil launch-cluster --help launch-cluster's main positional argument is the clusterName. This is simply the name of your cluster. If it does not exist yet, Toil will create it for you. Launch-Cluster Options --help -h also accepted. Displays this help menu. --tempDirRoot TEMPDIRROOT Path to the temporary directory where all temp files are created, by default uses the current working directory as the base. --version Display version. --provisioner CLOUDPROVIDER -p CLOUDPROVIDER also accepted. The provisioner for cluster auto-scaling. Both AWS and GCE are currently supported. --zone ZONE -z ZONE also accepted. The availability zone of the leader. This parameter can also be set via the TOIL_AWS_ZONE or TOIL_GCE_ZONE environment variables, or by the ec2_region_name parameter in your .boto file if using AWS, or derived from the instance metadata if using this utility on an existing EC2 instance. --leaderNodeType LEADERNODETYPE Non-preemptable node type to use for the cluster leader. --keyPairName KEYPAIRNAME The name of the AWS or ssh key pair to include on the instance. --boto BOTOPATH The path to the boto credentials directory. This is transferred to all nodes in order to access the AWS jobStore from non-AWS instances. --tag KEYVALUE KEYVALUE is specified as KEY=VALUE. -t KEY=VALUE also accepted. Tags are added to the AWS cluster for this node and all of its children. Tags are of the form: -t key1=value1 --tag key2=value2. Multiple tags are allowed and each tag needs its own flag. By default the cluster is tagged with: { "Name": clusterName, "Owner": IAM username }. --vpcSubnet VPCSUBNET VPC subnet ID to launch cluster leader in. Uses default subnet if not specified. This subnet needs to have auto assign IPs turned on. --nodeTypes NODETYPES Comma-separated list of node types to create while launching the leader. The syntax for each node type depends on the provisioner used. For the AWS provisioner this is the name of an EC2 instance type followed by a colon and the price in dollars to bid for a spot instance, for example 'c3.8xlarge:0.42'. Must also provide the --workers argument to specify how many workers of each node type to create. --workers WORKERS -w WORKERS also accepted. Comma-separated list of the number of workers of each node type to launch alongside the leader when the cluster is created. This can be useful if running toil without auto-scaling but with need of more hardware support. --leaderStorage LEADERSTORAGE Specify the size (in gigabytes) of the root volume for the leader instance. This is an EBS volume. --nodeStorage NODESTORAGE Specify the size (in gigabytes) of the root volume for any worker instances created when using the -w flag. This is an EBS volume. --nodeStorageOverrides NODESTORAGEOVERRIDES Comma-separated list of nodeType:nodeStorage that are used to override the default value from --nodeStorage for the specified nodeType(s). This is useful for heterogeneous jobs where some tasks require much more disk than others. Logging Options --logOff Same as -\-logCritical. --logCritical Turn on logging at level CRITICAL and above. (default is INFO) --logError Turn on logging at level ERROR and above. (default is INFO) --logWarning Turn on logging at level WARNING and above. (default is INFO) --logInfo Turn on logging at level INFO and above. (default is INFO) --logDebug Turn on logging at level DEBUG and above. (default is INFO) --logLevel LOGLEVEL Log at given level (may be either OFF (or CRITICAL), ERROR, WARN (or WARNING), INFO or DEBUG). (default is INFO) --logFile LOGFILE File to log in. --rotatingLogging Turn on rotating logging, which prevents log files getting too big. Ssh-Cluster Command Toil provides the ability to ssh into the leader of the cluster. This can be done as follows: $ toil ssh-cluster CLUSTER-NAME-HERE This will open a shell on the Toil leader and is used to start an Autoscaling run. Issues with docker prevent using screen and tmux when sshing the cluster (The shell doesn't know that it is a TTY which prevents it from allocating a new screen session). This can be worked around via $ script $ screen Simply running screen within script will get things working properly again. Finally, you can execute remote commands with the following syntax: $ toil ssh-cluster CLUSTER-NAME-HERE remoteCommand It is not advised that you run your Toil workflow using remote execution like this unless a tool like nohup is used to ensure the process does not die if the SSH connection is interrupted. For an example usage, see Autoscaling. Rsync-Cluster Command The most frequent use case for the rsync-cluster utility is deploying your Toil script to the Toil leader. Note that the syntax is the same as traditional rsync with the exception of the hostname before the colon. This is not needed in toil rsync-cluster since the hostname is automatically determined by Toil. Here is an example of its usage: $ toil rsync-cluster CLUSTER-NAME-HERE \ ~/localFile :/remoteDestination Destroy-Cluster Command The destroy-cluster command is the advised way to get rid of any Toil cluster launched using the Launch-Cluster Command command. It ensures that all attached nodes, volumes, security groups, etc. are deleted. If a node or cluster is shut down using Amazon's online portal residual resources may still be in use in the background. To delete a cluster run $ toil destroy-cluster CLUSTER-NAME-HERE Kill Command To kill all currently running jobs for a given jobstore, use the command toil kill file:my-jobstore
HPC ENVIRONMENTS
Toil is a flexible framework that can be leveraged in a variety of environments, including high-performance computing (HPC) environments. Toil provides support for a number of batch systems, including Grid Engine, Slurm, Torque and LSF, which are popular schedulers used in these environments. Toil also supports HTCondor, which is a popular scheduler for high-throughput computing (HTC). To use one of these batch systems specify the "-\-batchSystem" argument to the toil script. Due to the cost and complexity of maintaining support for these schedulers we currently consider them to be "community supported", that is the core development team does not regularly test or develop support for these systems. However, there are members of the Toil community currently deploying Toil in HPC environments and we welcome external contributions. Developing the support of a new or existing batch system involves extending the abstract batch system class toil.batchSystems.abstractBatchSystem.AbstractBatchSystem. Standard Output/Error from Batch System Jobs Standard output and error from batch system jobs (except for the Parasol and Mesos batch systems) are redirected to files in the toil-<workflowID> directory created within the temporary directory specified by the --workDir option; see optionsRef. Each file is named as follows: toil_job_<Toil job ID>_batch_<name of batch system>_<job ID from batch system>_<file description>.log, where <file description> is std_output for standard output, and std_error for standard error. HTCondor will also write job event log files with <file description> = job_events. If capturing standard output and error is desired, --workDir will generally need to be on a shared file system; otherwise if these are written to local temporary directories on each node (e.g. /tmp) Toil will not be able to retrieve them. Alternatively, the --noStdOutErr option forces Toil to discard all standard output and error from batch system jobs.
CWL IN TOIL
The Common Workflow Language (CWL) is an emerging standard for writing workflows that are portable across multiple workflow engines and platforms. Toil has full support for the CWL v1.0, v1.1, and v1.2 standards. Running CWL Locally The toil-cwl-runner command provides cwl-parsing functionality using cwltool, and leverages the job-scheduling and batch system support of Toil. To run in local batch mode, provide the CWL file and the input object file: $ toil-cwl-runner example.cwl example-job.yml For a simple example of CWL with Toil see cwlquickstart. Note for macOS + Docker + Toil When invoking CWL documents that make use of Docker containers if you see errors that look like docker: Error response from daemon: Mounts denied: The paths /var/...tmp are not shared from OS X and are not known to Docker. you may need to add export TMPDIR=/tmp/docker_tmp either in your startup file (.bashrc) or add it manually in your shell before invoking toil. Detailed Usage Instructions Help information can be found by using this toil command: $ toil-cwl-runner -h A more detailed example shows how we can specify both Toil and cwltool arguments for our workflow: $ toil-cwl-runner \ --singularity \ --jobStore my_jobStore \ --batchSystem lsf \ --workDir `pwd` \ --outdir `pwd` \ --logFile cwltoil.log \ --writeLogs `pwd` \ --logLevel DEBUG \ --retryCount 2 \ --maxLogFileSize 20000000000 \ --stats \ standard_bam_processing.cwl \ inputs.yaml In this example, we set the following options, which are all passed to Toil: --singularity: Specifies that all jobs with Docker format containers specified should be run using the Singularity container engine instead of the Docker container engine. --jobStore: Path to a folder which doesn't exist yet, which will contain the Toil jobstore and all related job-tracking information. --batchSystem: Use the specified HPC or Cloud-based cluster platform. --workDir: The directory where all temporary files will be created for the workflow. A subdirectory of this will be set as the $TMPDIR environment variable and this subdirectory can be referenced using the CWL parameter reference $(runtime.tmpdir) in CWL tools and workflows. --outdir: Directory where final File and Directory outputs will be written. References to these and other output types will be in the JSON object printed to the stdout stream after workflow execution. --logFile: Path to the main logfile with logs from all jobs. --writeLogs: Directory where all job logs will be stored. --retryCount: How many times to retry each Toil job. --maxLogFileSize: Logs that get larger than this value will be truncated. --stats: Save resources usages in json files that can be collected with the toil stats command after the workflow is done. --disable-streaming: Does not allow streaming of input files. This is enabled by default for files marked with streamable flag True and only for remote files when the jobStore is not on local machine. Running CWL in the Cloud To run in cloud and HPC configurations, you may need to provide additional command line parameters to select and configure the batch system to use. To run a CWL workflow in AWS with toil see awscwl. Running CWL within Toil Scripts A CWL workflow can be run indirectly in a native Toil script. However, this is not the standard way to run CWL workflows with Toil and doing so comes at the cost of job efficiency. For some use cases, such as running one process on multiple files, it may be useful. For example, if you want to run a CWL workflow with 3 YML files specifying different samples inputs, it could look something like: import os import subprocess from toil.common import Toil from toil.job import Job def initialize_jobs(job): job.fileStore.logToMaster('initialize_jobs') def runQC(job, cwl_file, cwl_filename, yml_file, yml_filename, outputs_dir, output_num): job.fileStore.logToMaster("runQC") tempDir = job.fileStore.getLocalTempDir() cwl = job.fileStore.readGlobalFile(cwl_file, userPath=os.path.join(tempDir, cwl_filename)) yml = job.fileStore.readGlobalFile(yml_file, userPath=os.path.join(tempDir, yml_filename)) subprocess.check_call(["toil-cwl-runner", cwl, yml]) output_filename = "output.txt" output_file = job.fileStore.writeGlobalFile(output_filename) job.fileStore.readGlobalFile(output_file, userPath=os.path.join(outputs_dir, "sample_" + output_num + "_" + output_filename)) return output_file if __name__ == "__main__": options = Job.Runner.getDefaultOptions("./toilWorkflowRun") options.logLevel = "INFO" options.clean = "always" with Toil(options) as toil: # specify the folder where the cwl and yml files live inputs_dir = os.path.join(os.path.dirname(os.path.abspath(__file__)), "cwlExampleFiles") # specify where you wish the outputs to be written outputs_dir = os.path.join(os.path.dirname(os.path.abspath(__file__)), "cwlExampleFiles") job0 = Job.wrapJobFn(initialize_jobs) cwl_filename = "hello.cwl" cwl_file = toil.importFile("file://" + os.path.abspath(os.path.join(inputs_dir, cwl_filename))) # add list of yml config inputs here or import and construct from file yml_files = ["hello1.yml", "hello2.yml", "hello3.yml"] i = 0 for yml in yml_files: i = i + 1 yml_file = toil.importFile("file://" + os.path.abspath(os.path.join(inputs_dir, yml))) yml_filename = yml job = Job.wrapJobFn(runQC, cwl_file, cwl_filename, yml_file, yml_filename, outputs_dir, output_num=str(i)) job0.addChild(job) toil.start(job0) Running CWL workflows with InplaceUpdateRequirement Some CWL workflows use the InplaceUpdateRequirement feature, which requires that operations on files have visible side effects that Toil's file store cannot support. If you need to run a workflow like this, you can make sure that all of your worker nodes have a shared filesystem, and use the --bypass-file-store option to toil-cwl-runner. This will make it leave all CWL intermediate files on disk and share them between jobs using file paths, instead of storing them in the file store and downloading them when jobs need them. Toil & CWL Tips See logs for just one job by using the full log file This requires knowing the job's toil-generated ID, which can be found in the log files. cat cwltoil.log | grep jobVM1fIs Grep for full tool commands from toil logs This gives you a more concise view of the commands being run (note that this information is only available from Toil when running with --logDebug). pcregrep -M "\[job .*\.cwl.*$\n(.* .*$\n)*" cwltoil.log # ^allows for multiline matching Find Bams that have been generated for specific step while pipeline is running: find . | grep -P '^./out_tmpdir.*_MD\.bam$' See what jobs have been run cat log/cwltoil.log | grep -oP "\[job .*.cwl\]" | sort | uniq or: cat log/cwltoil.log | grep -i "issued job" Get status of a workflow $ toil status /home/johnsoni/TEST_RUNS_3/TEST_run/tmp/jobstore-09ae0acc-c800-11e8-9d09-70106fb1697e <hostname> 2018-10-04 15:01:44,184 MainThread INFO toil.lib.bioio: Root logger is at level 'INFO', 'toil' logger at level 'INFO'. <hostname> 2018-10-04 15:01:44,185 MainThread INFO toil.utils.toilStatus: Parsed arguments <hostname> 2018-10-04 15:01:47,081 MainThread INFO toil.utils.toilStatus: Traversing the job graph gathering jobs. This may take a couple of minutes. Of the 286 jobs considered, there are 179 jobs with children, 107 jobs ready to run, 0 zombie jobs, 0 jobs with services, 0 services, and 0 jobs with log files currently in file:/home/user/jobstore-09ae0acc-c800-11e8-9d09-70106fb1697e. Toil Stats You can get run statistics broken down by CWL file. This only works once the workflow is finished: $ toil stats /path/to/jobstore The output will contain CPU, memory, and walltime information for all CWL job types: <hostname> 2018-10-15 12:06:19,003 MainThread INFO toil.lib.bioio: Root logger is at level 'INFO', 'toil' logger at level 'INFO'. <hostname> 2018-10-15 12:06:19,004 MainThread INFO toil.utils.toilStats: Parsed arguments <hostname> 2018-10-15 12:06:19,004 MainThread INFO toil.utils.toilStats: Checking if we have files for toil <hostname> 2018-10-15 12:06:19,004 MainThread INFO toil.utils.toilStats: Checked arguments Batch System: lsf Default Cores: 1 Default Memory: 10485760K Max Cores: 9.22337e+18 Total Clock: 106608.01 Total Runtime: 86634.11 Worker Count | Time* | Clock | Wait | Memory n | min med* ave max total | min med ave max total | min med ave max total | min med ave max total 1659 | 0.00 0.80 264.87 12595.59 439424.40 | 0.00 0.46 449.05 42240.74 744968.80 | -35336.69 0.16 -184.17 4230.65 -305544.39 | 48K 223K 1020K 40235K 1692300K Job Worker Jobs | min med ave max | 1077 1077 1077 1077 Count | Time* | Clock | Wait | Memory n | min med* ave max total | min med ave max total | min med ave max total | min med ave max total 1077 | 0.04 1.18 407.06 12593.43 438404.73 | 0.01 0.28 691.17 42240.35 744394.14 | -35336.83 0.27 -284.11 4230.49 -305989.41 | 135K 268K 1633K 40235K 1759734K ResolveIndirect Count | Time* | Clock | Wait | Memory n | min med* ave max total | min med ave max total | min med ave max total | min med ave max total 205 | 0.04 0.07 0.16 2.29 31.95 | 0.01 0.02 0.02 0.14 3.60 | 0.02 0.05 0.14 2.28 28.35 | 190K 266K 256K 314K 52487K CWLGather Count | Time* | Clock | Wait | Memory n | min med* ave max total | min med ave max total | min med ave max total | min med ave max total 40 | 0.05 0.17 0.29 1.90 11.62 | 0.01 0.02 0.02 0.05 0.80 | 0.03 0.14 0.27 1.88 10.82 | 188K 265K 250K 316K 10039K CWLWorkflow Count | Time* | Clock | Wait | Memory n | min med* ave max total | min med ave max total | min med ave max total | min med ave max total 205 | 0.09 0.40 0.98 13.70 200.82 | 0.04 0.15 0.16 1.08 31.78 | 0.04 0.26 0.82 12.62 169.04 | 190K 270K 257K 316K 52826K file:///home/johnsoni/pipeline_0.0.39/ACCESS-Pipeline/cwl_tools/expression_tools/group_waltz_files.cwl Count | Time* | Clock | Wait | Memory n | min med* ave max total | min med ave max total | min med ave max total | min med ave max total 99 | 0.29 0.49 0.59 2.50 58.11 | 0.14 0.26 0.29 1.04 28.95 | 0.14 0.22 0.29 1.48 29.16 | 135K 135K 135K 136K 13459K file:///home/johnsoni/pipeline_0.0.39/ACCESS-Pipeline/cwl_tools/expression_tools/make_sample_output_dirs.cwl Count | Time* | Clock | Wait | Memory n | min med* ave max total | min med ave max total | min med ave max total | min med ave max total 11 | 0.34 0.52 0.74 2.63 8.18 | 0.20 0.30 0.41 1.17 4.54 | 0.14 0.20 0.33 1.45 3.65 | 136K 136K 136K 136K 1496K file:///home/johnsoni/pipeline_0.0.39/ACCESS-Pipeline/cwl_tools/expression_tools/consolidate_files.cwl Count | Time* | Clock | Wait | Memory n | min med* ave max total | min med ave max total | min med ave max total | min med ave max total 8 | 0.31 0.59 0.71 1.80 5.69 | 0.18 0.35 0.37 0.63 2.94 | 0.13 0.27 0.34 1.17 2.75 | 136K 136K 136K 136K 1091K file:///home/johnsoni/pipeline_0.0.39/ACCESS-Pipeline/cwl_tools/bwa-mem/bwa-mem.cwl Count | Time* | Clock | Wait | Memory n | min med* ave max total | min med ave max total | min med ave max total | min med ave max total 22 | 895.76 3098.13 3587.34 12593.43 78921.51 | 2127.02 7910.31 8123.06 16959.13 178707.34 | -11049.84 -3827.96 -4535.72 19.49 -99785.83 | 5659K 5950K 5854K 6128K 128807K Understanding toil log files There is a worker_log.txt file for each job, this file is written to while the job is running, and deleted after the job finishes. The contents are printed to the main log file and transferred to a log file in the --logDir folder once the job is completed successfully. The new log file will be named something like: file:<path to cwl tool>.cwl_<job ID>.log file:---home-johnsoni-pipeline_1.1.14-ACCESS--Pipeline-cwl_tools-marianas-ProcessLoopUMIFastq.cwl_I-O-jobfGsQQw000.log This is the toil job command with spaces replaced by dashes.
WDL IN TOIL
Support is still in the alpha phase and should be able to handle basic wdl files. See the specification below for more details. How to Run a WDL file in Toil Recommended best practice when running wdl files is to first use the Broad's wdltool for syntax validation and generating the needed json input file. Full documentation can be found on the repository, and a precompiled jar binary can be downloaded here: wdltool (this requires java7). That means two steps. First, make sure your wdl file is valid and devoid of syntax errors by running java -jar wdltool.jar validate example_wdlfile.wdl Second, generate a complementary json file if your wdl file needs one. This json will contain keys for every necessary input that your wdl file needs to run: java -jar wdltool.jar inputs example_wdlfile.wdl When this json template is generated, open the file, and fill in values as necessary by hand. WDL files all require json files to accompany them. If no variable inputs are needed, a json file containing only '{}' may be required. Once a wdl file is validated and has an appropriate json file, workflows can be run in toil using: toil-wdl-runner example_wdlfile.wdl example_jsonfile.json See options below for more parameters. ENCODE Example from ENCODE-DCC To follow this example, you will need docker installed. The original workflow can be found here: https://github.com/ENCODE-DCC/pipeline-container We've included the wdl file and data files in the toil repository needed to run this example. First, download the example code and unzip. The file needed is "testENCODE/encode_mapping_workflow.wdl". Next, use wdltool (this requires java7) to validate this file: java -jar wdltool.jar validate encode_mapping_workflow.wdl Next, use wdltool to generate a json file for this wdl file: java -jar wdltool.jar inputs encode_mapping_workflow.wdl This json file once opened should look like this: { "encode_mapping_workflow.fastqs": "Array[File]", "encode_mapping_workflow.trimming_parameter": "String", "encode_mapping_workflow.reference": "File" } The trimming_parameter should be set to 'native'. Download the example code and unzip. Inside are two data files required for the run ENCODE_data/reference/GRCh38_chr21_bwa.tar.gz ENCODE_data/ENCFF000VOL_chr21.fq.gz Editing the json to include these as inputs, the json should now look something like this: { "encode_mapping_workflow.fastqs": ["/path/to/unzipped/ENCODE_data/ENCFF000VOL_chr21.fq.gz"], "encode_mapping_workflow.trimming_parameter": "native", "encode_mapping_workflow.reference": "/path/to/unzipped/ENCODE_data/reference/GRCh38_chr21_bwa.tar.gz" } The wdl and json files can now be run using the command toil-wdl-runner encode_mapping_workflow.wdl encode_mapping_workflow.json This should deposit the output files in the user's current working directory (to change this, specify a new directory with the '-o' option). GATK Examples from the Broad Simple examples of WDL can be found on the Broad's website as tutorials: https://software.broadinstitute.org/wdl/documentation/topic?name=wdl-tutorials. One can follow along with these tutorials, write their own wdl files following the directions and run them using either cromwell or toil. For example, in tutorial 1, if you've followed along and named your wdl file 'helloHaplotypeCall.wdl', then once you've validated your wdl file using wdltool (this requires java7) using java -jar wdltool.jar validate helloHaplotypeCaller.wdl and generated a json file (and subsequently typed in appropriate filepaths* and variables) using java -jar wdltool.jar inputs helloHaplotypeCaller.wdl · Absolute filepath inputs are recommended for local testing. then the wdl script can be run using toil-wdl-runner helloHaplotypeCaller.wdl helloHaplotypeCaller_inputs.json toilwdl.py Options '-o' or '-\-outdir': Specifies the output folder, and defaults to the current working directory if not specified by the user. '-\-dev_mode': Creates "AST.out", which holds a printed AST of the wdl file and "mappings.out", which holds the printed task, workflow, csv, and tsv dictionaries generated by the parser. Also saves the compiled toil python workflow file for debugging. Any number of arbitrary options may also be specified. These options will not be parsed immediately, but passed down as toil options once the wdl/json files are processed. For valid toil options, see the documentation: http://toil.readthedocs.io/en/latest/running/cliOptions.html Running WDL within Toil Scripts NOTE: A cromwell.jar file is needed in order to run a WDL workflow. A WDL workflow can be run indirectly in a native Toil script. However, this is not the standard way to run WDL workflows with Toil and doing so comes at the cost of job efficiency. For some use cases, such as running one process on multiple files, it may be useful. For example, if you want to run a WDL workflow with 3 JSON files specifying different samples inputs, it could look something like: import os import subprocess from toil.common import Toil from toil.job import Job def initialize_jobs(job): job.fileStore.logToMaster("initialize_jobs") def runQC(job, wdl_file, wdl_filename, json_file, json_filename, outputs_dir, jar_loc,output_num): job.fileStore.logToMaster("runQC") tempDir = job.fileStore.getLocalTempDir() wdl = job.fileStore.readGlobalFile(wdl_file, userPath=os.path.join(tempDir, wdl_filename)) json = job.fileStore.readGlobalFile(json_file, userPath=os.path.join(tempDir, json_filename)) subprocess.check_call(["java","-jar",jar_loc,"run",wdl,"--inputs",json]) output_filename = "output.txt" output_file = job.fileStore.writeGlobalFile(outputs_dir + output_filename) job.fileStore.readGlobalFile(output_file, userPath=os.path.join(outputs_dir, "sample_" + output_num + "_" + output_filename)) return output_file if __name__ == "__main__": options = Job.Runner.getDefaultOptions("./toilWorkflowRun") options.logLevel = "INFO" options.clean = "always" with Toil(options) as toil: # specify the folder where the wdl and json files live inputs_dir = "wdlExampleFiles/" # specify where you wish the outputs to be written outputs_dir = "wdlExampleFiles/" # specify the location of your cromwell jar jar_loc = os.path.abspath("wdlExampleFiles/cromwell-35.jar") job0 = Job.wrapJobFn(initialize_jobs) wdl_filename = "hello.wdl" wdl_file = toil.importFile("file://" + os.path.abspath(os.path.join(inputs_dir, wdl_filename))) # add list of yml config inputs here or import and construct from file json_files = ["hello1.json", "hello2.json", "hello3.json"] i = 0 for json in json_files: i = i + 1 json_file = toil.importFile("file://" + os.path.join(inputs_dir, json)) json_filename = json job = Job.wrapJobFn(runQC, wdl_file, wdl_filename, json_file, json_filename, outputs_dir, jar_loc, output_num=str(i)) job0.addChild(job) toil.start(job0) WDL Specifications WDL language specifications can be found here: https://github.com/broadinstitute/wdl/blob/develop/SPEC.md Implementing support for more features is currently underway, but a basic roadmap so far is: CURRENTLY IMPLEMENTED: · Scatter · Many Built-In Functions · Docker Calls · Handles Priority, and Output File Wrangling · Currently Handles Primitives and Arrays TO BE IMPLEMENTED: · Integrate Cloud Autoscaling Capacity More Robustly · WDL Files That "Import" Other WDL Files (Including URI Handling for 'http://' and 'https://')
WORKFLOW EXECUTION SERVICE (WES)
The GA4GH Workflow Execution Service (WES) is a standardized API for submitting and monitoring workflows. Toil has experimental support for setting up a WES server and executing CWL, WDL, and Toil workflows using the WES API. More information about the WES API specification can be found here. To get started with the Toil WES server, make sure that the server extra (extras) is installed. Preparing your WES environment The WES server requires Celery to distribute and execute workflows. To set up Celery: 1. Start RabbitMQ, which is the broker between the WES server and Celery workers: docker run -d --name wes-rabbitmq -p 5672:5672 rabbitmq:3.9.5 2. Start Celery workers: celery -A toil.server.celery_app worker --loglevel=INFO Starting a WES server To start a WES server on the default port 8080, run the Toil command: $ toil server The WES API will be hosted on the following URL: http://localhost:8080/ga4gh/wes/v1 To use another port, e.g.: 3000, you can specify the --port argument: $ toil server --port 3000 There are many other command line options. Help information can be found by using this command: $ toil server --help Below is a detailed summary of all available options: --debug Enable debug mode. --host HOST The host interface that the Toil server binds on. (default: "127.0.0.1"). --port PORT The port that the Toil server listens on. (default: 8080). --swagger_ui Enable the swagger UI on the ga4gh/wes/v1/ui endpoint. (default: False). --cors Enable Cross Origin Resource Sharing (CORS). This should only be turned on if the server is intended to be used by a website or domain. (default: False). --cors_origins ORIGIN Ignored if --cors is False. This sets the allowed origins for CORS. For details about CORS and its security risks, see the GA4GH docs on CORS. (default: "*"). --workers WORKERS Ignored if debug mode is on. The number of worker processes launched by the production WSGI server. (default: 2). --work_dir WORKDIR The directory where workflows should be stored. This directory should be empty or only contain previous workflows. (default: './workflows'). --opt ENGINE_OPTION Specify the default parameters to be sent to the workflow engine for each run. Accepts multiple values. Example: toil server --opt=--logLevel=CRITICAL --opt=--workDir=/tmp. Running the Server with docker-compose Instead of manually setting up the server components (toil server, RabbitMQ, and Celery), you can use the following docker-compose.yml file to orchestrate and link them together. Make sure to change /tmp/toil-workflows if you want Toil workflows to live somewhere else, and create the directory before starting the server. Also make sure to run it behind a firewall; it opens up the Toil server on port 8080 to anyone who connects. # Dockerfile FROM python:3.8 WORKDIR /app RUN pip install -e git+https://github.com/DataBiosphere/toil.git@9f9a83048344aa31583ba52ccae5f8f6ec23c8de#egg=toil[cwl,wdl,server] # docker-compose.yml version: "3.8" services: rabbitmq: image: rabbitmq:3.9.5 hostname: rabbitmq container_name: rabbitmq celery-worker: build: context: . dockerfile: Dockerfile container_name: celery-worker volumes: - /tmp/toil-workflows:/app/toil-workflows command: celery --broker=amqp://guest:guest@rabbitmq:5672// -A toil.server.celery_app worker --loglevel=INFO depends_on: - rabbitmq wes-server: build: context: . dockerfile: Dockerfile container_name: wes-server volumes: - /tmp/toil-workflows:/app/toil-workflows environment: - TOIL_WES_BROKER_URL=amqp://guest:guest@rabbitmq:5672// command: toil server --host 0.0.0.0 ports: - "127.0.0.1:8080:8080" depends_on: - rabbitmq - celery-worker Once everything is configured, simply run docker compose up to start the containers. Run docker compose down to stop and remove all containers. Note that this method only works if docker-compose is installed, which does not work on the Toil appliance. Running on a Toil cluster To run the server on a Toil leader instance on EC2: 1. Launch a Toil cluster with the toil launch-cluster command with the AWS provisioner 2. SSH into your cluster with the --sshOption=-L8080:localhost:8080 option to forward port 8080 3. Set up Celery workers required to run WES workflows (Preparing your WES environment) 4. Now, you can run the WES server with toil server on the Toil appliance. NOTE: To run the server in the background, run "nohup toil server &". WES API Endpoints As defined by the GA4GH WES API specification, the following endpoints with base path ga4gh/wes/v1/ are supported by Toil: ┌───────────────────────────┬──────────────────────────────────┐ │GET /service-info │ Get information about the │ │ │ Workflow Execution Service. │ ├───────────────────────────┼──────────────────────────────────┤ │GET /runs │ List the workflow runs. │ ├───────────────────────────┼──────────────────────────────────┤ │POST /runs │ Run a workflow. This endpoint │ │ │ creates a new workflow run and │ │ │ returns a run_id to monitor its │ │ │ progress. │ ├───────────────────────────┼──────────────────────────────────┤ │GET /runs/{run_id} │ Get detailed info about a │ │ │ workflow run. │ ├───────────────────────────┼──────────────────────────────────┤ │POST /runs/{run_id}/cancel │ Cancel a running workflow. │ ├───────────────────────────┼──────────────────────────────────┤ │GET /runs/{run_id}/status │ Get the status (overall state) │ │ │ of a workflow run. │ └───────────────────────────┴──────────────────────────────────┘ Submitting a Workflow Now that the WES API is up and running, we can submit and monitor workflows remotely using the WES API endpoints. A workflow can be submitted for execution using the POST /runs endpoint. As a quick example, we can submit the example CWL workflow from cwlquickstart to our WES API: # example.cwl cwlVersion: v1.0 class: CommandLineTool baseCommand: echo stdout: output.txt inputs: message: type: string inputBinding: position: 1 outputs: output: type: stdout using cURL: $ curl --location --request POST 'http://localhost:8080/ga4gh/wes/v1/runs' \ --form 'workflow_url="example.cwl"' \ --form 'workflow_type="cwl"' \ --form 'workflow_type_version="v1.0"' \ --form 'workflow_params="{\"message\": \"Hello world!\"}"' \ --form 'workflow_attachment=@"./toil_test_files/example.cwl"' { "run_id": "4deb8beb24894e9eb7c74b0f010305d1" } If the workflow is submitted successfully, a JSON object containing a run_id will be returned. The run_id is a unique identifier of your requested workflow, which can be used to monitor or cancel the run. There are a few required parameters that have to be set for all workflow submissions, which are the following: ┌──────────────────────┬──────────────────────────────────┐ │workflow_url │ The URL of the workflow to run. │ │ │ This can refer to a file from │ │ │ workflow_attachment. │ ├──────────────────────┼──────────────────────────────────┤ │workflow_type │ The type of workflow language. │ │ │ Toil currently supports one of │ │ │ the following: "CWL", "WDL", or │ │ │ "py". To run a Toil native │ │ │ python script, set this to "py". │ ├──────────────────────┼──────────────────────────────────┤ │workflow_type_version │ The version of the workflow │ │ │ language. Supported versions can │ │ │ be found by accessing the GET │ │ │ /service-info endpoint of your │ │ │ WES server. │ ├──────────────────────┼──────────────────────────────────┤ │workflow_params │ A JSON object that specifies the │ │ │ inputs of the workflow. │ └──────────────────────┴──────────────────────────────────┘ Additionally, the following optional parameters are also available: ┌───────────────────────────┬──────────────────────────────────┐ │workflow_attachment │ A list of files associated with │ │ │ the workflow run. │ ├───────────────────────────┼──────────────────────────────────┤ │workflow_engine_parameters │ A JSON key-value map of workflow │ │ │ engine parameters to send to the │ │ │ runner. │ │ │ │ │ │ Example: {"--logLevel": "INFO", │ │ │ "--workDir": "/tmp/"} │ ├───────────────────────────┼──────────────────────────────────┤ │tags │ A JSON key-value map of metadata │ │ │ associated with the workflow. │ └───────────────────────────┴──────────────────────────────────┘ For more details about these parameters, refer to the Run Workflow section in the WES API spec. Upload multiple files Looking at the body of the request of the previous example, note that the workflow_url is a relative URL that refers to the example.cwl file uploaded from the local path ./toil_test_files/example.cwl. To specify the file name (or subdirectory) of the remote destination file, set the filename field in the Content-Disposition header. You could also upload more than one file by providing the workflow_attachment parameter multiple times with different files. This can be shown by the following example: $ curl --location --request POST 'http://localhost:8080/ga4gh/wes/v1/runs' \ --form 'workflow_url="example.cwl"' \ --form 'workflow_type="cwl"' \ --form 'workflow_type_version="v1.0"' \ --form 'workflow_params="{\"message\": \"Hello world!\"}"' \ --form 'workflow_attachment=@"./toil_test_files/example.cwl"' \ --form 'workflow_attachment=@"./toil_test_files/2.fasta";filename=inputs/test.fasta' \ --form 'workflow_attachment=@"./toil_test_files/2.fastq";filename=inputs/test.fastq' On the server, the execution directory would have the following structure from the above request: execution/ ├── example.cwl ├── inputs │ ├── test.fasta | └── test.fastq └── wes_inputs.json Specify Toil options To pass Toil specific parameters to the workflow, you can include the workflow_engine_parameters parameter along with your request. For example, to set the logging level to INFO, and change the working directory of the workflow, simply include the following as workflow_engine_parameters: {"--logLevel": "INFO", "--workDir": "/tmp/"} These options would be appended at the end of existing parameters during command construction, which would override the default parameters if provided. (Default parameters that can be passed multiple times would not be overridden). Monitoring a Workflow With the run_id returned when submitting the workflow, we can check the status or get the full logs of the workflow run. Checking the state The GET /runs/{run_id}/status endpoint can be used to get a simple result with the overall state of your run: $ curl http://localhost:8080/ga4gh/wes/v1/runs/4deb8beb24894e9eb7c74b0f010305d1/status { "run_id": "4deb8beb24894e9eb7c74b0f010305d1", "state": "RUNNING" } The possible states here are: QUEUED, INITIALIZING, RUNNING, COMPLETE, EXECUTOR_ERROR, SYSTEM_ERROR, CANCELING, and CANCELED. Getting the full logs To get the detailed information about a workflow run, use the GET /runs/{run_id} endpoint: $ curl http://localhost:8080/ga4gh/wes/v1/runs/4deb8beb24894e9eb7c74b0f010305d1 { "run_id": "4deb8beb24894e9eb7c74b0f010305d1", "request": { "workflow_attachment": [ "example.cwl" ], "workflow_url": "example.cwl", "workflow_type": "cwl", "workflow_type_version": "v1.0", "workflow_params": { "message": "Hello world!" } }, "state": "RUNNING", "run_log": { "cmd": [ "toil-cwl-runner --outdir=/home/toil/workflows/4deb8beb24894e9eb7c74b0f010305d1/outputs --jobStore=file:/home/toil/workflows/4deb8beb24894e9eb7c74b0f010305d1/toil_job_store /home/toil/workflows/4deb8beb24894e9eb7c74b0f010305d1/execution/example.cwl /home/workflows/4deb8beb24894e9eb7c74b0f010305d1/execution/wes_inputs.json" ], "start_time": "2021-08-30T17:35:50Z", "end_time": null, "stdout": null, "stderr": null, "exit_code": null }, "task_logs": [], "outputs": {} } Canceling a run To cancel a workflow run, use the POST /runs/{run_id}/cancel endpoint: $ curl --location --request POST 'http://localhost:8080/ga4gh/wes/v1/runs/4deb8beb24894e9eb7c74b0f010305d1/cancel' { "run_id": "4deb8beb24894e9eb7c74b0f010305d1" }
DEVELOPING A WORKFLOW
This tutorial walks through the features of Toil necessary for developing a workflow using the Toil Python API. NOTE: "script" and "workflow" will be used interchangeably Scripting Quick Start To begin, consider this short toil script which illustrates defining a workflow: from toil.common import Toil from toil.job import Job def helloWorld(message, memory="2G", cores=2, disk="3G"): return f"Hello, world!, here's a message: {message}" if __name__ == "__main__": options = Job.Runner.getDefaultOptions("./toilWorkflowRun") options.logLevel = "OFF" options.clean = "always" hello_job = Job.wrapFn(helloWorld, "Woot") with Toil(options) as toil: print(toil.start(hello_job)) # prints "Hello, world!, ..." The workflow consists of a single job. The resource requirements for that job are (optionally) specified by keyword arguments (memory, cores, disk). The script is run using toil.job.Job.Runner.getDefaultOptions(). Below we explain the components of this code in detail. Job Basics The atomic unit of work in a Toil workflow is a Job. User scripts inherit from this base class to define units of work. For example, here is a more long-winded class-based version of the job in the quick start example: from toil.job import Job class HelloWorld(Job): def __init__(self, message): Job.__init__(self, memory="2G", cores=2, disk="3G") self.message = message def run(self, fileStore): return f"Hello, world! Here's a message: {self.message}" In the example a class, HelloWorld, is defined. The constructor requests 2 gigabytes of memory, 2 cores and 3 gigabytes of local disk to complete the work. The toil.job.Job.run() method is the function the user overrides to get work done. Here it just returns a message. It is also possible to log a message using toil.job.Job.log(), which will be registered in the log output of the leader process of the workflow: ... def run(self, fileStore): self.log(f"Hello, world! Here's a message: {self.message}") Invoking a Workflow We can add to the previous example to turn it into a complete workflow by adding the necessary function calls to create an instance of HelloWorld and to run this as a workflow containing a single job. For example: from toil.common import Toil from toil.job import Job class HelloWorld(Job): def __init__(self, message): Job.__init__(self, memory="2G", cores=2, disk="3G") self.message = message def run(self, fileStore): return f"Hello, world!, here's a message: {self.message}" if __name__ == "__main__": options = Job.Runner.getDefaultOptions("./toilWorkflowRun") options.logLevel = "OFF" options.clean = "always" hello_job = HelloWorld("Woot") with Toil(options) as toil: print(toil.start(hello_job)) NOTE: Do not include a . in the name of your python script (besides .py at the end). This is to allow toil to import the types and functions defined in your file while starting a new process. This uses the toil.common.Toil class, which is used to run and resume Toil workflows. It is used as a context manager and allows for preliminary setup, such as staging of files into the job store on the leader node. An instance of the class is initialized by specifying an options object. The actual workflow is then invoked by calling the toil.common.Toil.start() method, passing the root job of the workflow, or, if a workflow is being restarted, toil.common.Toil.restart() should be used. Note that the context manager should have explicit if else branches addressing restart and non restart cases. The boolean value for these if else blocks is toil.options.restart. For example: from toil.common import Toil from toil.job import Job class HelloWorld(Job): def __init__(self, message): Job.__init__(self, memory="2G", cores=2, disk="3G") self.message = message def run(self, fileStore): return f"Hello, world!, I have a message: {self.message}" if __name__ == "__main__": options = Job.Runner.getDefaultOptions("./toilWorkflowRun") options.logLevel = "INFO" options.clean = "always" with Toil(options) as toil: if not toil.options.restart: job = HelloWorld("Woot!") output = toil.start(job) else: output = toil.restart() print(output) The call to toil.job.Job.Runner.getDefaultOptions() creates a set of default options for the workflow. The only argument is a description of how to store the workflow's state in what we call a job-store. Here the job-store is contained in a directory within the current working directory called "toilWorkflowRun". Alternatively this string can encode other ways to store the necessary state, e.g. an S3 bucket object store location. By default the job-store is deleted if the workflow completes successfully. The workflow is executed in the final line, which creates an instance of HelloWorld and runs it as a workflow. Note all Toil workflows start from a single starting job, referred to as the root job. The return value of the root job is returned as the result of the completed workflow (see promises below to see how this is a useful feature!). Specifying Commandline Arguments To allow command line control of the options we can use the toil.job.Job.Runner.getDefaultArgumentParser() method to create a argparse.ArgumentParser object which can be used to parse command line options for a Toil script. For example: from toil.common import Toil from toil.job import Job class HelloWorld(Job): def __init__(self, message): Job.__init__(self, memory="2G", cores=2, disk="3G") self.message = message def run(self, fileStore): return "Hello, world!, here's a message: %s" % self.message if __name__ == "__main__": parser = Job.Runner.getDefaultArgumentParser() options = parser.parse_args() options.logLevel = "OFF" options.clean = "always" hello_job = HelloWorld("Woot") with Toil(options) as toil: print(toil.start(hello_job)) Creates a fully fledged script with all the options Toil exposed as command line arguments. Running this script with "--help" will print the full list of options. Alternatively an existing argparse.ArgumentParser or optparse.OptionParser object can have Toil script command line options added to it with the toil.job.Job.Runner.addToilOptions() method. Resuming a Workflow In the event that a workflow fails, either because of programmatic error within the jobs being run, or because of node failure, the workflow can be resumed. Workflows can only not be reliably resumed if the job-store itself becomes corrupt. Critical to resumption is that jobs can be rerun, even if they have apparently completed successfully. Put succinctly, a user defined job should not corrupt its input arguments. That way, regardless of node, network or leader failure the job can be restarted and the workflow resumed. To resume a workflow specify the "restart" option in the options object passed to toil.common.Toil.start(). If node failures are expected it can also be useful to use the integer "retryCount" option, which will attempt to rerun a job retryCount number of times before marking it fully failed. In the common scenario that a small subset of jobs fail (including retry attempts) within a workflow Toil will continue to run other jobs until it can do no more, at which point toil.common.Toil.start() will raise a toil.leader.FailedJobsException exception. Typically at this point the user can decide to fix the script and resume the workflow or delete the job-store manually and rerun the complete workflow. Functions and Job Functions Defining jobs by creating class definitions generally involves the boilerplate of creating a constructor. To avoid this the classes toil.job.FunctionWrappingJob and toil.job.JobFunctionWrappingTarget allow functions to be directly converted to jobs. For example, the quick start example (repeated here): from toil.common import Toil from toil.job import Job def helloWorld(message, memory="2G", cores=2, disk="3G"): return f"Hello, world!, here's a message: {message}" if __name__ == "__main__": options = Job.Runner.getDefaultOptions("./toilWorkflowRun") options.logLevel = "OFF" options.clean = "always" hello_job = Job.wrapFn(helloWorld, "Woot") with Toil(options) as toil: print(toil.start(hello_job)) # prints "Hello, world!, ..." Is equivalent to the previous example, but using a function to define the job. The function call: Job.wrapFn(helloWorld, "Woot") Creates the instance of the toil.job.FunctionWrappingTarget that wraps the function. The keyword arguments memory, cores and disk allow resource requirements to be specified as before. Even if they are not included as keyword arguments within a function header they can be passed as arguments when wrapping a function as a job and will be used to specify resource requirements. We can also use the function wrapping syntax to a job function, a function whose first argument is a reference to the wrapping job. Just like a self argument in a class, this allows access to the methods of the wrapping job, see toil.job.JobFunctionWrappingTarget. For example: from toil.common import Toil from toil.job import Job def helloWorld(job, message): job.log(f"Hello world, I have a message: {message}") if __name__ == "__main__": options = Job.Runner.getDefaultOptions("./toilWorkflowRun") options.logLevel = "INFO" options.clean = "always" hello_job = Job.wrapJobFn(helloWorld, "Woot!") with Toil(options) as toil: toil.start(hello_job) Here helloWorld() is a job function. It uses the toil.job.Job.log() to log a message that will be printed to the output console. Here the only subtle difference to note is the line: hello_job = Job.wrapJobFn(helloWorld, "Woot") Which uses the function toil.job.Job.wrapJobFn() to wrap the job function instead of toil.job.Job.wrapFn() which wraps a vanilla function. Workflows with Multiple Jobs A parent job can have child jobs and follow-on jobs. These relationships are specified by methods of the job class, e.g. toil.job.Job.addChild() and toil.job.Job.addFollowOn(). Considering a set of jobs the nodes in a job graph and the child and follow-on relationships the directed edges of the graph, we say that a job B that is on a directed path of child/follow-on edges from a job A in the job graph is a successor of A, similarly A is a predecessor of B. A parent job's child jobs are run directly after the parent job has completed, and in parallel. The follow-on jobs of a job are run after its child jobs and their successors have completed. They are also run in parallel. Follow-ons allow the easy specification of cleanup tasks that happen after a set of parallel child tasks. The following shows a simple example that uses the earlier helloWorld() job function: from toil.common import Toil from toil.job import Job def helloWorld(job, message, memory="2G", cores=2, disk="3G"): job.log(f"Hello world, I have a message: {message}") if __name__ == "__main__": options = Job.Runner.getDefaultOptions("./toilWorkflowRun") options.logLevel = "INFO" options.clean = "always" j1 = Job.wrapJobFn(helloWorld, "first") j2 = Job.wrapJobFn(helloWorld, "second or third") j3 = Job.wrapJobFn(helloWorld, "second or third") j4 = Job.wrapJobFn(helloWorld, "last") j1.addChild(j2) j1.addChild(j3) j1.addFollowOn(j4) with Toil(options) as toil: toil.start(j1) In the example four jobs are created, first j1 is run, then j2 and j3 are run in parallel as children of j1, finally j4 is run as a follow-on of j1. There are multiple short hand functions to achieve the same workflow, for example: from toil.common import Toil from toil.job import Job def helloWorld(job, message, memory="2G", cores=2, disk="3G"): job.log(f"Hello world, I have a message: {message}") if __name__ == "__main__": options = Job.Runner.getDefaultOptions("./toilWorkflowRun") options.logLevel = "INFO" options.clean = "always" j1 = Job.wrapJobFn(helloWorld, "first") j2 = j1.addChildJobFn(helloWorld, "second or third") j3 = j1.addChildJobFn(helloWorld, "second or third") j4 = j1.addFollowOnJobFn(helloWorld, "last") with Toil(options) as toil: toil.start(j1) Equivalently defines the workflow, where the functions toil.job.Job.addChildJobFn() and toil.job.Job.addFollowOnJobFn() are used to create job functions as children or follow-ons of an earlier job. Jobs graphs are not limited to trees, and can express arbitrary directed acyclic graphs. For a precise definition of legal graphs see toil.job.Job.checkJobGraphForDeadlocks(). The previous example could be specified as a DAG as follows: from toil.common import Toil from toil.job import Job def helloWorld(job, message, memory="2G", cores=2, disk="3G"): job.log(f"Hello world, I have a message: {message}") if __name__ == "__main__": options = Job.Runner.getDefaultOptions("./toilWorkflowRun") options.logLevel = "INFO" options.clean = "always" j1 = Job.wrapJobFn(helloWorld, "first") j2 = j1.addChildJobFn(helloWorld, "second or third") j3 = j1.addChildJobFn(helloWorld, "second or third") j4 = j2.addChildJobFn(helloWorld, "last") j3.addChild(j4) with Toil(options) as toil: toil.start(j1) Note the use of an extra child edge to make j4 a child of both j2 and j3. Dynamic Job Creation The previous examples show a workflow being defined outside of a job. However, Toil also allows jobs to be created dynamically within jobs. For example: from toil.common import Toil from toil.job import Job def binaryStringFn(job, depth, message=""): if depth > 0: job.addChildJobFn(binaryStringFn, depth-1, message + "0") job.addChildJobFn(binaryStringFn, depth-1, message + "1") else: job.log(f"Binary string: {message}") if __name__ == "__main__": options = Job.Runner.getDefaultOptions("./toilWorkflowRun") options.logLevel = "INFO" options.clean = "always" with Toil(options) as toil: toil.start(Job.wrapJobFn(binaryStringFn, depth=5)) The job function binaryStringFn logs all possible binary strings of length n (here n=5), creating a total of 2^(n+2) - 1 jobs dynamically and recursively. Static and dynamic creation of jobs can be mixed in a Toil workflow, with jobs defined within a job or job function being created at run time. Promises The previous example of dynamic job creation shows variables from a parent job being passed to a child job. Such forward variable passing is naturally specified by recursive invocation of successor jobs within parent jobs. This can also be achieved statically by passing around references to the return variables of jobs. In Toil this is achieved with promises, as illustrated in the following example: from toil.common import Toil from toil.job import Job def fn(job, i): job.log("i is: %s" % i, level=100) return i + 1 if __name__ == "__main__": options = Job.Runner.getDefaultOptions("./toilWorkflowRun") options.logLevel = "INFO" options.clean = "always" j1 = Job.wrapJobFn(fn, 1) j2 = j1.addChildJobFn(fn, j1.rv()) j3 = j1.addFollowOnJobFn(fn, j2.rv()) with Toil(options) as toil: toil.start(j1) Running this workflow results in three log messages from the jobs: i is 1 from j1, i is 2 from j2 and i is 3 from j3. The return value from the first job is promised to the second job by the call to toil.job.Job.rv() in the following line: j2 = j1.addChildFn(fn, j1.rv()) The value of j1.rv() is a promise, rather than the actual return value of the function, because j1 for the given input has at that point not been evaluated. A promise (toil.job.Promise) is essentially a pointer to for the return value that is replaced by the actual return value once it has been evaluated. Therefore, when j2 is run the promise becomes 2. Promises also support indexing of return values: def parent(job): indexable = Job.wrapJobFn(fn) job.addChild(indexable) job.addFollowOnFn(raiseWrap, indexable.rv(2)) def raiseWrap(arg): raise RuntimeError(arg) # raises "2" def fn(job): return (0, 1, 2, 3) Promises can be quite useful. For example, we can combine dynamic job creation with promises to achieve a job creation process that mimics the functional patterns possible in many programming languages: from toil.common import Toil from toil.job import Job def binaryStrings(job, depth, message=""): if depth > 0: s = [job.addChildJobFn(binaryStrings, depth - 1, message + "0").rv(), job.addChildJobFn(binaryStrings, depth - 1, message + "1").rv()] return job.addFollowOnFn(merge, s).rv() return [message] def merge(strings): return strings[0] + strings[1] if __name__ == "__main__": options = Job.Runner.getDefaultOptions("./toilWorkflowRun") options.loglevel = "OFF" options.clean = "always" with Toil(options) as toil: print(toil.start(Job.wrapJobFn(binaryStrings, depth=5))) The return value l of the workflow is a list of all binary strings of length 10, computed recursively. Although a toy example, it demonstrates how closely Toil workflows can mimic typical programming patterns. Promised Requirements Promised requirements are a special case of Promises that allow a job's return value to be used as another job's resource requirements. This is useful when, for example, a job's storage requirement is determined by a file staged to the job store by an earlier job: import os from toil.common import Toil from toil.job import Job, PromisedRequirement def parentJob(job): downloadJob = Job.wrapJobFn(stageFn, "file://" + os.path.realpath(__file__), cores=0.1, memory='32M', disk='1M') job.addChild(downloadJob) analysis = Job.wrapJobFn(analysisJob, fileStoreID=downloadJob.rv(0), disk=PromisedRequirement(downloadJob.rv(1))) job.addFollowOn(analysis) def stageFn(job, url, cores=1): importedFile = job.fileStore.import_file(url) return importedFile, importedFile.size def analysisJob(job, fileStoreID, cores=2): # now do some analysis on the file pass if __name__ == "__main__": options = Job.Runner.getDefaultOptions("./toilWorkflowRun") options.logLevel = "INFO" options.clean = "always" with Toil(options) as toil: toil.start(Job.wrapJobFn(parentJob)) Note that this also makes use of the size attribute of the FileID object. This promised requirements mechanism can also be used in combination with an aggregator for multiple jobs' output values: def parentJob(job): aggregator = [] for fileNum in range(0, 10): downloadJob = Job.wrapJobFn(stageFn, "file://" + os.path.realpath(__file__), cores=0.1, memory='32M', disk='1M') job.addChild(downloadJob) aggregator.append(downloadJob) analysis = Job.wrapJobFn(analysisJob, fileStoreID=downloadJob.rv(0), disk=PromisedRequirement(lambda xs: sum(xs), [j.rv(1) for j in aggregator])) job.addFollowOn(analysis) Limitations Just like regular promises, the return value must be determined prior to scheduling any job that depends on the return value. In our example above, notice how the dependent jobs were follow ons to the parent while promising jobs are children of the parent. This ordering ensures that all promises are properly fulfilled. FileID The toil.fileStore.FileID class is a small wrapper around Python's builtin string class. It is used to represent a file's ID in the file store, and has a size attribute that is the file's size in bytes. This object is returned by importFile and writeGlobalFile. Managing files within a workflow It is frequently the case that a workflow will want to create files, both persistent and temporary, during its run. The toil.fileStores.abstractFileStore.AbstractFileStore class is used by jobs to manage these files in a manner that guarantees cleanup and resumption on failure. The toil.job.Job.run() method has a file store instance as an argument. The following example shows how this can be used to create temporary files that persist for the length of the job, be placed in a specified local disk of the node and that will be cleaned up, regardless of failure, when the job finishes: from toil.common import Toil from toil.job import Job class LocalFileStoreJob(Job): def run(self, fileStore): # self.tempDir will always contain the name of a directory within the allocated disk space reserved for the job scratchDir = self.tempDir # Similarly create a temporary file. scratchFile = fileStore.getLocalTempFile() if __name__ == "__main__": options = Job.Runner.getDefaultOptions("./toilWorkflowRun") options.logLevel = "INFO" options.clean = "always" # Create an instance of FooJob which will have at least 2 gigabytes of storage space. j = LocalFileStoreJob(disk="2G") # Run the workflow with Toil(options) as toil: toil.start(j) Job functions can also access the file store for the job. The equivalent of the LocalFileStoreJob class is def localFileStoreJobFn(job): scratchDir = job.tempDir scratchFile = job.fileStore.getLocalTempFile() Note that the fileStore attribute is accessed as an attribute of the job argument. In addition to temporary files that exist for the duration of a job, the file store allows the creation of files in a global store, which persists during the workflow and are globally accessible (hence the name) between jobs. For example: import os from toil.common import Toil from toil.job import Job def globalFileStoreJobFn(job): job.log("The following example exercises all the methods provided " "by the toil.fileStores.abstractFileStore.AbstractFileStore class") # Create a local temporary file. scratchFile = job.fileStore.getLocalTempFile() # Write something in the scratch file. with open(scratchFile, 'w') as fH: fH.write("What a tangled web we weave") # Write a copy of the file into the file-store; fileID is the key that can be used to retrieve the file. # This write is asynchronous by default fileID = job.fileStore.writeGlobalFile(scratchFile) # Write another file using a stream; fileID2 is the # key for this second file. with job.fileStore.writeGlobalFileStream(cleanup=True) as (fH, fileID2): fH.write(b"Out brief candle") # Now read the first file; scratchFile2 is a local copy of the file that is read-only by default. scratchFile2 = job.fileStore.readGlobalFile(fileID) # Read the second file to a desired location: scratchFile3. scratchFile3 = os.path.join(job.tempDir, "foo.txt") job.fileStore.readGlobalFile(fileID2, userPath=scratchFile3) # Read the second file again using a stream. with job.fileStore.readGlobalFileStream(fileID2) as fH: print(fH.read()) # This prints "Out brief candle" # Delete the first file from the global file-store. job.fileStore.deleteGlobalFile(fileID) # It is unnecessary to delete the file keyed by fileID2 because we used the cleanup flag, # which removes the file after this job and all its successors have run (if the file still exists) if __name__ == "__main__": options = Job.Runner.getDefaultOptions("./toilWorkflowRun") options.logLevel = "INFO" options.clean = "always" with Toil(options) as toil: toil.start(Job.wrapJobFn(globalFileStoreJobFn)) The example demonstrates the global read, write and delete functionality of the file-store, using both local copies of the files and streams to read and write the files. It covers all the methods provided by the file store interface. What is obvious is that the file-store provides no functionality to update an existing "global" file, meaning that files are, barring deletion, immutable. Also worth noting is that there is no file system hierarchy for files in the global file store. These limitations allow us to fairly easily support different object stores and to use caching to limit the amount of network file transfer between jobs. Staging of Files into the Job Store External files can be imported into or exported out of the job store prior to running a workflow when the toil.common.Toil context manager is used on the leader. The context manager provides methods toil.common.Toil.importFile(), and toil.common.Toil.exportFile() for this purpose. The destination and source locations of such files are described with URLs passed to the two methods. Local files can be imported and exported as relative paths, and should be relative to the directory where the toil workflow is initially run from. Using absolute paths and appropriate schema where possible (prefixing with "file://" or "s3:/" for example), make imports and exports less ambiguous and is recommended. A list of the currently supported URLs can be found at toil.jobStores.abstractJobStore.AbstractJobStore.importFile(). To import an external file into the job store as a shared file, pass the optional sharedFileName parameter to that method. If a workflow fails for any reason an imported file acts as any other file in the job store. If the workflow was configured such that it not be cleaned up on a failed run, the file will persist in the job store and needs not be staged again when the workflow is resumed. Example: import os from toil.common import Toil from toil.job import Job class HelloWorld(Job): def __init__(self, id): Job.__init__(self, memory="2G", cores=2, disk="3G") self.inputFileID = id def run(self, fileStore): with fileStore.readGlobalFileStream(self.inputFileID, encoding='utf-8') as fi: with fileStore.writeGlobalFileStream(encoding='utf-8') as (fo, outputFileID): fo.write(fi.read() + 'World!') return outputFileID if __name__ == "__main__": options = Job.Runner.getDefaultOptions("./toilWorkflowRun") options.logLevel = "INFO" options.clean = "always" with Toil(options) as toil: if not toil.options.restart: ioFileDirectory = os.path.join(os.path.dirname(os.path.abspath(__file__)), "stagingExampleFiles") inputFileID = toil.importFile("file://" + os.path.abspath(os.path.join(ioFileDirectory, "in.txt"))) outputFileID = toil.start(HelloWorld(inputFileID)) else: outputFileID = toil.restart() toil.exportFile(outputFileID, "file://" + os.path.abspath(os.path.join(ioFileDirectory, "out.txt"))) Using Docker Containers in Toil Docker containers are commonly used with Toil. The combination of Toil and Docker allows for pipelines to be fully portable between any platform that has both Toil and Docker installed. Docker eliminates the need for the user to do any other tool installation or environment setup. In order to use Docker containers with Toil, Docker must be installed on all workers of the cluster. Instructions for installing Docker can be found on the Docker website. When using Toil-based autoscaling, Docker will be automatically set up on the cluster's worker nodes, so no additional installation steps are necessary. Further information on using Toil-based autoscaling can be found in the Autoscaling documentation. In order to use docker containers in a Toil workflow, the container can be built locally or downloaded in real time from an online docker repository like Quay. If the container is not in a repository, the container's layers must be accessible on each node of the cluster. When invoking docker containers from within a Toil workflow, it is strongly recommended that you use dockerCall(), a toil job function provided in toil.lib.docker. dockerCall leverages docker's own python API, and provides container cleanup on job failure. When docker containers are run without this feature, failed jobs can result in resource leaks. Docker's API can be found at docker-py. In order to use dockerCall, your installation of Docker must be set up to run without sudo. Instructions for setting this up can be found here. An example of a basic dockerCall is below: dockerCall(job=job, tool='quay.io/ucsc_cgl/bwa', workDir=job.tempDir, parameters=['index', '/data/reference.fa']) Note the assumption that reference.fa file is located in /data. This is Toil's standard convention as a mount location to reduce boilerplate when calling dockerCall. Users can choose their own mount locations by supplying a volumes kwarg to dockerCall, such as: volumes={working_dir: {'bind': '/data', 'mode': 'rw'}}, where working_dir is an absolute path on the user's filesystem. dockerCall can also be added to workflows like any other job function: import os from toil.common import Toil from toil.job import Job from toil.lib.docker import apiDockerCall align = Job.wrapJobFn(apiDockerCall, image='ubuntu', working_dir=os.getcwd(), parameters=['ls', '-lha']) if __name__ == "__main__": options = Job.Runner.getDefaultOptions("./toilWorkflowRun") options.logLevel = "INFO" options.clean = "always" with Toil(options) as toil: toil.start(align) cgl-docker-lib contains dockerCall-compatible Dockerized tools that are commonly used in bioinformatics analysis. The documentation provides guidelines for developing your own Docker containers that can be used with Toil and dockerCall. In order for a container to be compatible with dockerCall, it must have an ENTRYPOINT set to a wrapper script, as described in cgl-docker-lib containerization standards. This can be set by passing in the optional keyword argument, 'entrypoint'. Example: entrypoint=["/bin/bash","-c"] dockerCall supports currently the 75 keyword arguments found in the python Docker API, under the 'run' command. Services It is sometimes desirable to run services, such as a database or server, concurrently with a workflow. The toil.job.Job.Service class provides a simple mechanism for spawning such a service within a Toil workflow, allowing precise specification of the start and end time of the service, and providing start and end methods to use for initialization and cleanup. The following simple, conceptual example illustrates how services work: from toil.common import Toil from toil.job import Job class DemoService(Job.Service): def start(self, fileStore): # Start up a database/service here # Return a value that enables another process to connect to the database return "loginCredentials" def check(self): # A function that if it returns False causes the service to quit # If it raises an exception the service is killed and an error is reported return True def stop(self, fileStore): # Cleanup the database here pass j = Job() s = DemoService() loginCredentialsPromise = j.addService(s) def dbFn(loginCredentials): # Use the login credentials returned from the service's start method to connect to the service pass j.addChildFn(dbFn, loginCredentialsPromise) if __name__ == "__main__": options = Job.Runner.getDefaultOptions("./toilWorkflowRun") options.logLevel = "INFO" options.clean = "always" with Toil(options) as toil: toil.start(j) In this example the DemoService starts a database in the start method, returning an object from the start method indicating how a client job would access the database. The service's stop method cleans up the database, while the service's check method is polled periodically to check the service is alive. A DemoService instance is added as a service of the root job j, with resource requirements specified. The return value from toil.job.Job.addService() is a promise to the return value of the service's start method. When the promised is fulfilled it will represent how to connect to the database. The promise is passed to a child job of j, which uses it to make a database connection. The services of a job are started before any of its successors have been run and stopped after all the successors of the job have completed successfully. Multiple services can be created per job, all run in parallel. Additionally, services can define sub-services using toil.job.Job.Service.addChild(). This allows complex networks of services to be created, e.g. Apache Spark clusters, within a workflow. Checkpoints Services complicate resuming a workflow after failure, because they can create complex dependencies between jobs. For example, consider a service that provides a database that multiple jobs update. If the database service fails and loses state, it is not clear that just restarting the service will allow the workflow to be resumed, because jobs that created that state may have already finished. To get around this problem Toil supports checkpoint jobs, specified as the boolean keyword argument checkpoint to a job or wrapped function, e.g.: j = Job(checkpoint=True) A checkpoint job is rerun if one or more of its successors fails its retry attempts, until it itself has exhausted its retry attempts. Upon restarting a checkpoint job all its existing successors are first deleted, and then the job is rerun to define new successors. By checkpointing a job that defines a service, upon failure of the service the database and the jobs that access the service can be redefined and rerun. To make the implementation of checkpoint jobs simple, a job can only be a checkpoint if when first defined it has no successors, i.e. it can only define successors within its run method. Encapsulation Let A be a root job potentially with children and follow-ons. Without an encapsulated job the simplest way to specify a job B which runs after A and all its successors is to create a parent of A, call it Ap, and then make B a follow-on of Ap. e.g.: from toil.common import Toil from toil.job import Job if __name__ == "__main__": # A is a job with children and follow-ons, for example: A = Job() A.addChild(Job()) A.addFollowOn(Job()) # B is a job which needs to run after A and its successors B = Job() # The way to do this without encapsulation is to make a parent of A, Ap, and make B a follow-on of Ap. Ap = Job() Ap.addChild(A) Ap.addFollowOn(B) options = Job.Runner.getDefaultOptions("./toilWorkflowRun") options.logLevel = "INFO" options.clean = "always" with Toil(options) as toil: print(toil.start(Ap)) An encapsulated job E(A) of A saves making Ap, instead we can write: from toil.common import Toil from toil.job import Job if __name__ == "__main__": # A A = Job() A.addChild(Job()) A.addFollowOn(Job()) # Encapsulate A A = A.encapsulate() # B is a job which needs to run after A and its successors B = Job() # With encapsulation A and its successor subgraph appear to be a single job, hence: A.addChild(B) options = Job.Runner.getDefaultOptions("./toilWorkflowRun") options.logLevel = "INFO" options.clean = "always" with Toil(options) as toil: print(toil.start(A)) Note the call to toil.job.Job.encapsulate() creates the toil.job.Job.EncapsulatedJob. Depending on Toil If you are packing your workflow(s) as a pip-installable distribution on PyPI, you might be tempted to declare Toil as a dependency in your setup.py, via the install_requires keyword argument to setup(). Unfortunately, this does not work, for two reasons: For one, Toil uses Setuptools' extra mechanism to manage its own optional dependencies. If you explicitly declared a dependency on Toil, you would have to hard-code a particular combination of extras (or no extras at all), robbing the user of the choice what Toil extras to install. Secondly, and more importantly, declaring a dependency on Toil would only lead to Toil being installed on the leader node of a cluster, but not the worker nodes. Auto-deployment does not work here because Toil cannot auto-deploy itself, the classic "Which came first, chicken or egg?" problem. In other words, you shouldn't explicitly depend on Toil. Document the dependency instead (as in "This workflow needs Toil version X.Y.Z to be installed") and optionally add a version check to your setup.py. Refer to the check_version() function in the toil-lib project's setup.py for an example. Alternatively, you can also just depend on toil-lib and you'll get that check for free. If your workflow depends on a dependency of Toil, consider not making that dependency explicit either. If you do, you risk a version conflict between your project and Toil. The pip utility may silently ignore that conflict, breaking either Toil or your workflow. It is safest to simply assume that Toil installs that dependency for you. The only downside is that you are locked into the exact version of that dependency that Toil declares. But such is life with Python, which, unlike Java, has no means of dependencies belonging to different software components within the same process, and whose favored software distribution utility is incapable of properly resolving overlapping dependencies and detecting conflicts. Best Practices for Dockerizing Toil Workflows Computational Genomics Lab's Dockstore based production system provides workflow authors a way to run Dockerized versions of their pipeline in an automated, scalable fashion. To be compatible with this system of a workflow should meet the following requirements. In addition to the Docker container, a common workflow language descriptor file is needed. For inputs: · Only command line arguments should be used for configuring the workflow. If the workflow relies on a configuration file, like Toil-RNAseq or ProTECT, a wrapper script inside the Docker container can be used to parse the CLI and generate the necessary configuration file. · All inputs to the pipeline should be explicitly enumerated rather than implicit. For example, don't rely on one FASTQ read's path to discover the location of its pair. This is necessary since all inputs are mapped to their own isolated directories when the Docker is called via Dockstore. · All inputs must be documented in the CWL descriptor file. Examples of this file can be seen in both Toil-RNAseq and ProTECT. For outputs: · All outputs should be written to a local path rather than S3. · Take care to package outputs in a local and user-friendly way. For example, don't tar up all output if there are specific files that will care to see individually. · All output file names should be deterministic and predictable. For example, don't prepend the name of an output file with PASS/FAIL depending on the outcome of the pipeline. · All outputs must be documented in the CWL descriptor file. Examples of this file can be seen in both Toil-RNAseq and ProTECT.
TOIL CLASS API
The Toil class configures and starts a Toil run. class toil.common.Toil(options: argparse.Namespace) A context manager that represents a Toil workflow, specifically the batch system, job store, and its configuration. __init__(options: argparse.Namespace) -> None Initialize a Toil object from the given options. Note that this is very light-weight and that the bulk of the work is done when the context is entered. Parameters options -- command line options specified by the user config Type toil.common.Config start(rootJob) Invoke a Toil workflow with the given job as the root for an initial run. This method must be called in the body of a with Toil(...) as toil: statement. This method should not be called more than once for a workflow that has not finished. Parameters rootJob (toil.job.Job) -- The root job of the workflow Returns The root job's return value restart() Restarts a workflow that has been interrupted. Returns The root job's return value classmethod getJobStore(locator: str) -> AbstractJobStore Create an instance of the concrete job store implementation that matches the given locator. Parameters locator (str) -- The location of the job store to be represent by the instance Returns an instance of a concrete subclass of AbstractJobStore static createBatchSystem(config: toil.common.Config) -> AbstractBatchSystem Creates an instance of the batch system specified in the given config. Parameters config (toil.common.Config) -- the current configuration Return type batchSystems.abstractBatchSystem.AbstractBatchSystem Returns an instance of a concrete subclass of AbstractBatchSystem import_file(src_uri: str, shared_file_name: Optional[str] = None, symlink: bool = False) -> Optional[Union[toil.fileStores.FileID, str]] Imports the file at the given URL into job store. See toil.jobStores.abstractJobStore.AbstractJobStore.importFile() for a full description export_file(file_id: Union[toil.fileStores.FileID, str], dst_uri: str) -> None Exports file to destination pointed at by the destination URL. See toil.jobStores.abstractJobStore.AbstractJobStore.exportFile() for a full description static normalize_uri(uri: str, check_existence: bool = False) -> str Given a URI, if it has no scheme, prepend "file:". Parameters check_existence -- If set, raise an error if a URI points to a local file that does not exist. static getToilWorkDir(configWorkDir: Optional[str] = None) -> str Returns a path to a writable directory under which per-workflow directories exist. This directory is always required to exist on a machine, even if the Toil worker has not run yet. If your workers and leader have different temp directories, you may need to set TOIL_WORKDIR. Parameters configWorkDir (str) -- Value passed to the program using the --workDir flag Returns Path to the Toil work directory, constant across all machines Return type str classmethod getLocalWorkflowDir(workflowID: str, configWorkDir: Optional[str] = None) -> str Returns a path to the directory where worker directories and the cache will be located for this workflow on this machine. Parameters configWorkDir -- Value passed to the program using the --workDir flag Returns Path to the local workflow directory on this machine writePIDFile() Write a the pid of this process to a file in the jobstore. Overwriting the current contents of pid.log is a feature, not a bug of this method. Other methods will rely on always having the most current pid available. So far there is no reason to store any old pids.
JOB STORE API
The job store interface is an abstraction layer that that hides the specific details of file storage, for example standard file systems, S3, etc. The AbstractJobStore API is implemented to support a give file store, e.g. S3. Implement this API to support a new file store. class toil.jobStores.abstractJobStore.AbstractJobStore(locator: str) Represents the physical storage for the jobs and files in a Toil workflow. JobStores are responsible for storing toil.job.JobDescription (which relate jobs to each other) and files. Actual toil.job.Job objects are stored in files, referenced by JobDescriptions. All the non-file CRUD methods the JobStore provides deal in JobDescriptions and not full, executable Jobs. To actually get ahold of a toil.job.Job, use toil.job.Job.loadJob() with a JobStore and the relevant JobDescription. __init__(locator: str) -> None Create an instance of the job store. The instance will not be fully functional until either initialize() or resume() is invoked. Note that the destroy() method may be invoked on the object with or without prior invocation of either of these two methods. Takes and stores the locator string for the job store, which will be accessible via self.locator. initialize(config: toil.common.Config) -> None Initialize this job store. Create the physical storage for this job store, allocate a workflow ID and persist the given Toil configuration to the store. Parameters config -- the Toil configuration to initialize this job store with. The given configuration will be updated with the newly allocated workflow ID. Raises JobStoreExistsException -- if the physical storage for this job store already exists write_config() -> None Persists the value of the AbstractJobStore.config attribute to the job store, so that it can be retrieved later by other instances of this class. resume() -> None Connect this instance to the physical storage it represents and load the Toil configuration into the AbstractJobStore.config attribute. Raises NoSuchJobStoreException -- if the physical storage for this job store doesn't exist property config: toil.common.Config Return the Toil configuration associated with this job store. property locator: str Get the locator that defines the job store, which can be used to connect to it. setRootJob(rootJobStoreID: toil.fileStores.FileID) -> None Set the root job of the workflow backed by this job store. set_root_job(job_id: toil.fileStores.FileID) -> None Set the root job of the workflow backed by this job store. Parameters job_id -- The ID of the job to set as root load_root_job() -> toil.job.JobDescription Loads the JobDescription for the root job in the current job store. Raises toil.job.JobException -- If no root job is set or if the root job doesn't exist in this job store Returns The root job. create_root_job(job_description: toil.job.JobDescription) -> toil.job.JobDescription Create the given JobDescription and set it as the root job in this job store. Parameters job_description -- JobDescription to save and make the root job. get_root_job_return_value() -> Any Parse the return value from the root job. Raises an exception if the root job hasn't fulfilled its promise yet. import_file(src_uri: str, shared_file_name: Optional[str] = None, hardlink: bool = False, symlink: bool = False) -> Optional[toil.fileStores.FileID] Imports the file at the given URL into job store. The ID of the newly imported file is returned. If the name of a shared file name is provided, the file will be imported as such and None is returned. If an executable file on the local filesystem is uploaded, its executability will be preserved when it is downloaded. Currently supported schemes are: · 's3' for objects in Amazon S3 e.g. s3://bucket/key · 'file' for local files e.g. file:///local/file/path · 'http' e.g. http://someurl.com/path · 'gs' e.g. gs://bucket/file Parameters · src_uri (str) -- URL that points to a file or object in the storage mechanism of a supported URL scheme e.g. a blob in an AWS s3 bucket. · shared_file_name (str) -- Optional name to assign to the imported file within the job store Returns The jobStoreFileID of the imported file or None if sharedFileName was given Return type toil.fileStores.FileID or None export_file(file_id: toil.fileStores.FileID, dst_uri: str) -> None Exports file to destination pointed at by the destination URL. The exported file will be executable if and only if it was originally uploaded from an executable file on the local filesystem. Refer to AbstractJobStore.import_file() documentation for currently supported URL schemes. Note that the helper method _exportFile is used to read from the source and write to destination. To implement any optimizations that circumvent this, the _exportFile method should be overridden by subclasses of AbstractJobStore. Parameters · file_id (str) -- The id of the file in the job store that should be exported. · dst_uri (str) -- URL that points to a file or object in the storage mechanism of a supported URL scheme e.g. a blob in an AWS s3 bucket. abstract classmethod get_size(url: urllib.parse.ParseResult) -> None Get the size in bytes of the file at the given URL, or None if it cannot be obtained. Parameters url (ParseResult) -- URL that points to a file or object in the storage mechanism of a supported URL scheme e.g. a blob in an AWS s3 bucket. abstract destroy() -> None The inverse of initialize(), this method deletes the physical storage represented by this instance. While not being atomic, this method is at least idempotent, as a means to counteract potential issues with eventual consistency exhibited by the underlying storage mechanisms. This means that if the method fails (raises an exception), it may (and should be) invoked again. If the underlying storage mechanism is eventually consistent, even a successful invocation is not an ironclad guarantee that the physical storage vanished completely and immediately. A successful invocation only guarantees that the deletion will eventually happen. It is therefore recommended to not immediately reuse the same job store location for a new Toil workflow. get_env() -> Dict[str, str] Returns a dictionary of environment variables that this job store requires to be set in order to function properly on a worker. Return type dict[str,str] clean(jobCache: Optional[Dict[str, toil.job.JobDescription]] = None) -> toil.job.JobDescription Function to cleanup the state of a job store after a restart. Fixes jobs that might have been partially updated. Resets the try counts and removes jobs that are not successors of the current root job. Parameters jobCache -- if a value it must be a dict from job ID keys to JobDescription object values. Jobs will be loaded from the cache (which can be downloaded from the job store in a batch) instead of piecemeal when recursed into. abstract assign_job_id(job_description: toil.job.JobDescription) -> None Get a new jobStoreID to be used by the described job, and assigns it to the JobDescription. Files associated with the assigned ID will be accepted even if the JobDescription has never been created or updated. Parameters job_description (toil.job.JobDescription) -- The JobDescription to give an ID to batch() -> Iterator[None] If supported by the batch system, calls to create() with this context manager active will be performed in a batch after the context manager is released. abstract create_job(job_description: toil.job.JobDescription) -> toil.job.JobDescription Writes the given JobDescription to the job store. The job must have an ID assigned already. Must call jobDescription.pre_update_hook() Returns The JobDescription passed. Return type toil.job.JobDescription abstract job_exists(job_id: str) -> bool Indicates whether a description of the job with the specified jobStoreID exists in the job store Return type bool abstract get_public_url(file_name: str) -> str Returns a publicly accessible URL to the given file in the job store. The returned URL may expire as early as 1h after its been returned. Throw an exception if the file does not exist. Parameters file_name (str) -- the jobStoreFileID of the file to generate a URL for Raises NoSuchFileException -- if the specified file does not exist in this job store Return type str abstract get_shared_public_url(shared_file_name: str) -> str Differs from getPublicUrl() in that this method is for generating URLs for shared files written by writeSharedFileStream(). Returns a publicly accessible URL to the given file in the job store. The returned URL starts with 'http:', 'https:' or 'file:'. The returned URL may expire as early as 1h after its been returned. Throw an exception if the file does not exist. Parameters shared_file_name (str) -- The name of the shared file to generate a publically accessible url for. Raises NoSuchFileException -- raised if the specified file does not exist in the store Return type str abstract load_job(job_id: str) -> toil.job.JobDescription Loads the description of the job referenced by the given ID, assigns it the job store's config, and returns it. May declare the job to have failed (see toil.job.JobDescription.setupJobAfterFailure()) if there is evidence of a failed update attempt. Parameters job_id -- the ID of the job to load Raises NoSuchJobException -- if there is no job with the given ID abstract update_job(job_description: toil.job.JobDescription) -> None Persists changes to the state of the given JobDescription in this store atomically. Must call jobDescription.pre_update_hook() Parameters job (toil.job.JobDescription) -- the job to write to this job store abstract delete_job(job_id: str) -> None Removes the JobDescription from the store atomically. You may not then subsequently call load(), write(), update(), etc. with the same jobStoreID or any JobDescription bearing it. This operation is idempotent, i.e. deleting a job twice or deleting a non-existent job will succeed silently. Parameters job_id (str) -- the ID of the job to delete from this job store jobs() -> Iterator[toil.job.JobDescription] Best effort attempt to return iterator on JobDescriptions for all jobs in the store. The iterator may not return all jobs and may also contain orphaned jobs that have already finished successfully and should not be rerun. To guarantee you get any and all jobs that can be run instead construct a more expensive ToilState object Returns Returns iterator on jobs in the store. The iterator may or may not contain all jobs and may contain invalid jobs Return type Iterator[toil.job.jobDescription] abstract write_file(local_path: str, job_id: Optional[str] = None, cleanup: bool = False) -> str Takes a file (as a path) and places it in this job store. Returns an ID that can be used to retrieve the file at a later time. The file is written in a atomic manner. It will not appear in the jobStore until the write has successfully completed. Parameters · local_path (str) -- the path to the local file that will be uploaded to the job store. The last path component (basename of the file) will remain associated with the file in the file store, if supported, so that the file can be searched for by name or name glob. · job_id (str) -- the id of a job, or None. If specified, the may be associated with that job in a job-store-specific way. This may influence the returned ID. · cleanup (bool) -- Whether to attempt to delete the file when the job whose jobStoreID was given as jobStoreID is deleted with jobStore.delete(job). If jobStoreID was not given, does nothing. Raises · ConcurrentFileModificationException -- if the file was modified concurrently during an invocation of this method · NoSuchJobException -- if the job specified via jobStoreID does not exist FIXME: some implementations may not raise this Returns an ID referencing the newly created file and can be used to read the file in the future. Return type str abstract write_file_stream(job_id: Optional[str] = None, cleanup: bool = False, basename: Optional[str] = None, encoding: Optional[str] = None, errors: Optional[str] = None) -> Iterator[Tuple[IO[bytes], str]] Similar to writeFile, but returns a context manager yielding a tuple of 1) a file handle which can be written to and 2) the ID of the resulting file in the job store. The yielded file handle does not need to and should not be closed explicitly. The file is written in a atomic manner. It will not appear in the jobStore until the write has successfully completed. Parameters · job_id (str) -- the id of a job, or None. If specified, the may be associated with that job in a job-store-specific way. This may influence the returned ID. · cleanup (bool) -- Whether to attempt to delete the file when the job whose jobStoreID was given as jobStoreID is deleted with jobStore.delete(job). If jobStoreID was not given, does nothing. · basename (str) -- If supported by the implementation, use the given file basename so that when searching the job store with a query matching that basename, the file will be detected. · encoding (str) -- the name of the encoding used to encode the file. Encodings are the same as for encode(). Defaults to None which represents binary mode. · errors (str) -- an optional string that specifies how encoding errors are to be handled. Errors are the same as for open(). Defaults to 'strict' when an encoding is specified. Raises · ConcurrentFileModificationException -- if the file was modified concurrently during an invocation of this method · NoSuchJobException -- if the job specified via jobStoreID does not exist FIXME: some implementations may not raise this Returns a context manager yielding a file handle which can be written to and an ID that references the newly created file and can be used to read the file in the future. Return type Iterator[Tuple[IO[bytes], str]] abstract get_empty_file_store_id(job_id: Optional[str] = None, cleanup: bool = False, basename: Optional[str] = None) -> str Creates an empty file in the job store and returns its ID. Call to fileExists(getEmptyFileStoreID(jobStoreID)) will return True. Parameters · job_id (str) -- the id of a job, or None. If specified, the may be associated with that job in a job-store-specific way. This may influence the returned ID. · cleanup (bool) -- Whether to attempt to delete the file when the job whose jobStoreID was given as jobStoreID is deleted with jobStore.delete(job). If jobStoreID was not given, does nothing. · basename (str) -- If supported by the implementation, use the given file basename so that when searching the job store with a query matching that basename, the file will be detected. Returns a jobStoreFileID that references the newly created file and can be used to reference the file in the future. Return type str abstract read_file(file_id: str, local_path: str, symlink: bool = False) -> None Copies or hard links the file referenced by jobStoreFileID to the given local file path. The version will be consistent with the last copy of the file written/updated. If the file in the job store is later modified via updateFile or updateFileStream, it is implementation-defined whether those writes will be visible at localFilePath. The file is copied in an atomic manner. It will not appear in the local file system until the copy has completed. The file at the given local path may not be modified after this method returns! Note! Implementations of readFile need to respect/provide the executable attribute on FileIDs. Parameters · file_id (str) -- ID of the file to be copied · local_path (str) -- the local path indicating where to place the contents of the given file in the job store · symlink (bool) -- whether the reader can tolerate a symlink. If set to true, the job store may create a symlink instead of a full copy of the file or a hard link. abstract read_file_stream(file_id: Union[toil.fileStores.FileID, str], encoding: Optional[str] = None, errors: Optional[str] = None) -> Union[ContextManager[_io.BytesIO], ContextManager[TextIO]] Similar to readFile, but returns a context manager yielding a file handle which can be read from. The yielded file handle does not need to and should not be closed explicitly. Parameters · file_id (str) -- ID of the file to get a readable file handle for · encoding (str) -- the name of the encoding used to decode the file. Encodings are the same as for decode(). Defaults to None which represents binary mode. · errors (str) -- an optional string that specifies how encoding errors are to be handled. Errors are the same as for open(). Defaults to 'strict' when an encoding is specified. Returns a context manager yielding a file handle which can be read from Return type Iterator[Union[BytesIO, TextIO]] abstract delete_file(file_id: str) -> None Deletes the file with the given ID from this job store. This operation is idempotent, i.e. deleting a file twice or deleting a non-existent file will succeed silently. Parameters file_id (str) -- ID of the file to delete fileExists(jobStoreFileID: str) -> bool Determine whether a file exists in this job store. abstract file_exists(file_id: str) -> bool Determine whether a file exists in this job store. Parameters file_id -- an ID referencing the file to be checked getFileSize(jobStoreFileID: str) -> int Get the size of the given file in bytes. abstract get_file_size(file_id: str) -> int Get the size of the given file in bytes, or 0 if it does not exist when queried. Note that job stores which encrypt files might return overestimates of file sizes, since the encrypted file may have been padded to the nearest block, augmented with an initialization vector, etc. Parameters file_id (str) -- an ID referencing the file to be checked Return type int updateFile(jobStoreFileID: str, localFilePath: str) -> None Replaces the existing version of a file in the job store. abstract update_file(file_id: str, local_path: str) -> None Replaces the existing version of a file in the job store. Throws an exception if the file does not exist. Parameters · file_id -- the ID of the file in the job store to be updated · local_path -- the local path to a file that will overwrite the current version in the job store Raises · ConcurrentFileModificationException -- if the file was modified concurrently during an invocation of this method · NoSuchFileException -- if the specified file does not exist abstract update_file_stream(file_id: str, encoding: Optional[str] = None, errors: Optional[str] = None) -> Iterator[IO[Any]] Replaces the existing version of a file in the job store. Similar to writeFile, but returns a context manager yielding a file handle which can be written to. The yielded file handle does not need to and should not be closed explicitly. Parameters · file_id (str) -- the ID of the file in the job store to be updated · encoding (str) -- the name of the encoding used to encode the file. Encodings are the same as for encode(). Defaults to None which represents binary mode. · errors (str) -- an optional string that specifies how encoding errors are to be handled. Errors are the same as for open(). Defaults to 'strict' when an encoding is specified. Raises · ConcurrentFileModificationException -- if the file was modified concurrently during an invocation of this method · NoSuchFileException -- if the specified file does not exist abstract write_shared_file_stream(shared_file_name: str, encrypted: Optional[bool] = None, encoding: Optional[str] = None, errors: Optional[str] = None) -> Iterator[IO[bytes]] Returns a context manager yielding a writable file handle to the global file referenced by the given name. File will be created in an atomic manner. Parameters · shared_file_name (str) -- A file name matching AbstractJobStore.fileNameRegex, unique within this job store · encrypted (bool) -- True if the file must be encrypted, None if it may be encrypted or False if it must be stored in the clear. · encoding (str) -- the name of the encoding used to encode the file. Encodings are the same as for encode(). Defaults to None which represents binary mode. · errors (str) -- an optional string that specifies how encoding errors are to be handled. Errors are the same as for open(). Defaults to 'strict' when an encoding is specified. Raises ConcurrentFileModificationException -- if the file was modified concurrently during an invocation of this method Returns a context manager yielding a writable file handle Return type Iterator[IO[bytes]] abstract read_shared_file_stream(shared_file_name: str, encoding: Optional[str] = None, errors: Optional[str] = None) -> Iterator[_io.BytesIO] Returns a context manager yielding a readable file handle to the global file referenced by the given name. Parameters · shared_file_name (str) -- A file name matching AbstractJobStore.fileNameRegex, unique within this job store · encoding (str) -- the name of the encoding used to decode the file. Encodings are the same as for decode(). Defaults to None which represents binary mode. · errors (str) -- an optional string that specifies how encoding errors are to be handled. Errors are the same as for open(). Defaults to 'strict' when an encoding is specified. Returns a context manager yielding a readable file handle Return type Iterator[BytesIO] abstract write_logs(msg: str) -> None Stores a message as a log in the jobstore. Parameters msg (str) -- the string to be written Raises ConcurrentFileModificationException -- if the file was modified concurrently during an invocation of this method abstract read_logs(callback: Callable[[...], Any], read_all: bool = False) -> int Reads logs accumulated by the write_logs() method. For each log this method calls the given callback function with the message as an argument (rather than returning logs directly, this method must be supplied with a callback which will process log messages). Only unread logs will be read unless the read_all parameter is set. Parameters · callback (Callable) -- a function to be applied to each of the stats file handles found · read_all (bool) -- a boolean indicating whether to read the already processed stats files in addition to the unread stats files Raises ConcurrentFileModificationException -- if the file was modified concurrently during an invocation of this method Returns the number of stats files processed Return type int
TOIL JOB API
Functions to wrap jobs and return values (promises). FunctionWrappingJob The subclass of Job for wrapping user functions. class toil.job.FunctionWrappingJob(userFunction, *args, **kwargs) Job used to wrap a function. In its run method the wrapped function is called. __init__(userFunction, *args, **kwargs) Parameters userFunction (callable) -- The function to wrap. It will be called with *args and **kwargs as arguments. The keywords memory, cores, disk, preemptable and checkpoint are reserved keyword arguments that if specified will be used to determine the resources required for the job, as toil.job.Job.__init__(). If they are keyword arguments to the function they will be extracted from the function definition, but may be overridden by the user (as you would expect). run(fileStore) Override this function to perform work and dynamically create successor jobs. Parameters fileStore -- Used to create local and globally sharable temporary files and to send log messages to the leader process. Returns The return value of the function can be passed to other jobs by means of toil.job.Job.rv(). JobFunctionWrappingJob The subclass of FunctionWrappingJob for wrapping user job functions. class toil.job.JobFunctionWrappingJob(userFunction, *args, **kwargs) A job function is a function whose first argument is a Job instance that is the wrapping job for the function. This can be used to add successor jobs for the function and perform all the functions the Job class provides. To enable the job function to get access to the toil.fileStores.abstractFileStore.AbstractFileStore instance (see toil.job.Job.run()), it is made a variable of the wrapping job called fileStore. To specify a job's resource requirements the following default keyword arguments can be specified: · memory · disk · cores For example to wrap a function into a job we would call: Job.wrapJobFn(myJob, memory='100k', disk='1M', cores=0.1) run(fileStore) Override this function to perform work and dynamically create successor jobs. Parameters fileStore -- Used to create local and globally sharable temporary files and to send log messages to the leader process. Returns The return value of the function can be passed to other jobs by means of toil.job.Job.rv(). EncapsulatedJob The subclass of Job for encapsulating a job, allowing a subgraph of jobs to be treated as a single job. class toil.job.EncapsulatedJob(job, unitName=None) A convenience Job class used to make a job subgraph appear to be a single job. Let A be the root job of a job subgraph and B be another job we'd like to run after A and all its successors have completed, for this use encapsulate: # Job A and subgraph, Job B A, B = A(), B() Aprime = A.encapsulate() Aprime.addChild(B) # B will run after A and all its successors have completed, A and its subgraph of # successors in effect appear to be just one job. If the job being encapsulated has predecessors (e.g. is not the root job), then the encapsulated job will inherit these predecessors. If predecessors are added to the job being encapsulated after the encapsulated job is created then the encapsulating job will NOT inherit these predecessors automatically. Care should be exercised to ensure the encapsulated job has the proper set of predecessors. The return value of an encapsulated job (as accessed by the toil.job.Job.rv() function) is the return value of the root job, e.g. A().encapsulate().rv() and A().rv() will resolve to the same value after A or A.encapsulate() has been run. __init__(job, unitName=None) Parameters · job (toil.job.Job) -- the job to encapsulate. · unitName (str) -- human-readable name to identify this job instance. addChild(childJob) Add a childJob to be run as child of this job. Child jobs will be run directly after this job's toil.job.Job.run() method has completed. Returns childJob: for call chaining addService(service, parentService=None) Add a service. The toil.job.Job.Service.start() method of the service will be called after the run method has completed but before any successors are run. The service's toil.job.Job.Service.stop() method will be called once the successors of the job have been run. Services allow things like databases and servers to be started and accessed by jobs in a workflow. Raises toil.job.JobException -- If service has already been made the child of a job or another service. Parameters · service -- Service to add. · parentService -- Service that will be started before 'service' is started. Allows trees of services to be established. parentService must be a service of this job. Returns a promise that will be replaced with the return value from toil.job.Job.Service.start() of service in any successor of the job. addFollowOn(followOnJob) Add a follow-on job. Follow-on jobs will be run after the child jobs and their successors have been run. Returns followOnJob for call chaining rv(*path) -> toil.job.Promise Create a promise (toil.job.Promise). The "promise" representing a return value of the job's run method, or, in case of a function-wrapping job, the wrapped function's return value. Parameters path ((Any)) -- Optional path for selecting a component of the promised return value. If absent or empty, the entire return value will be used. Otherwise, the first element of the path is used to select an individual item of the return value. For that to work, the return value must be a list, dictionary or of any other type implementing the __getitem__() magic method. If the selected item is yet another composite value, the second element of the path can be used to select an item from it, and so on. For example, if the return value is [6,{'a':42}], .rv(0) would select 6 , rv(1) would select {'a':3} while rv(1,'a') would select 3. To select a slice from a return value that is slicable, e.g. tuple or list, the path element should be a slice object. For example, assuming that the return value is [6, 7, 8, 9] then .rv(slice(1, 3)) would select [7, 8]. Note that slicing really only makes sense at the end of path. Returns A promise representing the return value of this jobs toil.job.Job.run() method. Return type toil.job.Promise prepareForPromiseRegistration(jobStore) Ensure that a promise by this job (the promissor) can register with the promissor when another job referring to the promise (the promissee) is being serialized. The promissee holds the reference to the promise (usually as part of the the job arguments) and when it is being pickled, so will the promises it refers to. Pickling a promise triggers it to be registered with the promissor. Returns Promise The class used to reference return values of jobs/services not yet run/started. class toil.job.Promise(*args) References a return value from a method as a promise before the method itself is run. References a return value from a toil.job.Job.run() or toil.job.Job.Service.start() method as a promise before the method itself is run. Let T be a job. Instances of Promise (termed a promise) are returned by T.rv(), which is used to reference the return value of T's run function. When the promise is passed to the constructor (or as an argument to a wrapped function) of a different, successor job the promise will be replaced by the actual referenced return value. This mechanism allows a return values from one job's run method to be input argument to job before the former job's run function has been executed. filesToDelete = {} A set of IDs of files containing promised values when we know we won't need them anymore __init__(job: toil.job.Job, path: Any) Initialize this promise. Parameters · job (Job) -- the job whose return value this promise references · path -- see Job.rv() class toil.job.PromisedRequirement(valueOrCallable, *args) Class for dynamically allocating job function resource requirements. (involving toil.job.Promise instances.) Use when resource requirements depend on the return value of a parent function. PromisedRequirements can be modified by passing a function that takes the Promise as input. For example, let f, g, and h be functions. Then a Toil workflow can be defined as follows:: A = Job.wrapFn(f) B = A.addChildFn(g, cores=PromisedRequirement(A.rv()) C = B.addChildFn(h, cores=PromisedRequirement(lambda x: 2*x, B.rv())) __init__(valueOrCallable, *args) Initialize this Promised Requirement. Parameters · valueOrCallable -- A single Promise instance or a function that takes args as input parameters. · args (int or Promise) -- variable length argument list getValue() Return PromisedRequirement value. static convertPromises(kwargs: Dict[str, Any]) -> bool Return True if reserved resource keyword is a Promise or PromisedRequirement instance. Converts Promise instance to PromisedRequirement. Parameters kwargs -- function keyword arguments
JOB METHODS API
Jobs are the units of work in Toil which are composed into workflows. class toil.job.Job(memory: Optional[Union[int, str]] = None, cores: Optional[Union[int, float, str]] = None, disk: Optional[Union[int, str]] = None, preemptable: Optional[Union[bool, int, str]] = None, unitName: Optional[str] = '', checkpoint: Optional[bool] = False, displayName: Optional[str] = '', descriptionClass: Optional[str] = None) Class represents a unit of work in toil. __init__(memory: Optional[Union[int, str]] = None, cores: Optional[Union[int, float, str]] = None, disk: Optional[Union[int, str]] = None, preemptable: Optional[Union[bool, int, str]] = None, unitName: Optional[str] = '', checkpoint: Optional[bool] = False, displayName: Optional[str] = '', descriptionClass: Optional[str] = None) -> None Job initializer. This method must be called by any overriding constructor. Parameters · memory (int or string convertible by toil.lib.conversions.human2bytes to an int) -- the maximum number of bytes of memory the job will require to run. · cores (float, int, or string convertible by toil.lib.conversions.human2bytes to an int) -- the number of CPU cores required. · disk (int or string convertible by toil.lib.conversions.human2bytes to an int) -- the amount of local disk space required by the job, expressed in bytes. · preemptable (bool, int in {0, 1}, or string in {'false', 'true'} in any case) -- if the job can be run on a preemptable node. · unitName (str) -- Human-readable name for this instance of the job. · checkpoint (bool) -- if any of this job's successor jobs completely fails, exhausting all their retries, remove any successor jobs and rerun this job to restart the subtree. Job must be a leaf vertex in the job graph when initially defined, see toil.job.Job.checkNewCheckpointsAreCutVertices(). · displayName (str) -- Human-readable job type display name. · descriptionClass (class) -- Override for the JobDescription class used to describe the job. property jobStoreID Get the ID of this Job. Return type str|toil.job.TemporaryID property description Expose the JobDescription that describes this job. Return type toil.job.JobDescription property disk: int The maximum number of bytes of disk the job will require to run. Return type int property memory The maximum number of bytes of memory the job will require to run. Return type int property cores The number of CPU cores required. Return type int|float property preemptable Whether the job can be run on a preemptable node. Return type bool property checkpoint Determine if the job is a checkpoint job or not. Return type bool assignConfig(config: toil.common.Config) Assign the given config object. It will be used by various actions implemented inside the Job class. Parameters config -- Config object to query run(fileStore: AbstractFileStore) -> Any Override this function to perform work and dynamically create successor jobs. Parameters fileStore -- Used to create local and globally sharable temporary files and to send log messages to the leader process. Returns The return value of the function can be passed to other jobs by means of toil.job.Job.rv(). addChild(childJob: toil.job.Job) -> toil.job.Job Add a childJob to be run as child of this job. Child jobs will be run directly after this job's toil.job.Job.run() method has completed. Returns childJob: for call chaining hasChild(childJob: toil.job.Job) -> bool Check if childJob is already a child of this job. Returns True if childJob is a child of the job, else False. addFollowOn(followOnJob: toil.job.Job) -> toil.job.Job Add a follow-on job. Follow-on jobs will be run after the child jobs and their successors have been run. Returns followOnJob for call chaining hasPredecessor(job: toil.job.Job) -> bool Check if a given job is already a predecessor of this job. hasFollowOn(followOnJob: toil.job.Job) -> bool Check if given job is already a follow-on of this job. Returns True if the followOnJob is a follow-on of this job, else False. addService(service: Service, parentService: Optional[Service] = None) -> Promise Add a service. The toil.job.Job.Service.start() method of the service will be called after the run method has completed but before any successors are run. The service's toil.job.Job.Service.stop() method will be called once the successors of the job have been run. Services allow things like databases and servers to be started and accessed by jobs in a workflow. Raises toil.job.JobException -- If service has already been made the child of a job or another service. Parameters · service -- Service to add. · parentService -- Service that will be started before 'service' is started. Allows trees of services to be established. parentService must be a service of this job. Returns a promise that will be replaced with the return value from toil.job.Job.Service.start() of service in any successor of the job. hasService(service: Service) -> bool Return True if the given Service is a service of this job, and False otherwise. addChildFn(fn: Callable, *args, **kwargs) -> toil.job.FunctionWrappingJob Add a function as a child job. Parameters fn -- Function to be run as a child job with *args and **kwargs as arguments to this function. See toil.job.FunctionWrappingJob for reserved keyword arguments used to specify resource requirements. Returns The new child job that wraps fn. addFollowOnFn(fn: Callable, *args, **kwargs) -> toil.job.FunctionWrappingJob Add a function as a follow-on job. Parameters fn -- Function to be run as a follow-on job with *args and **kwargs as arguments to this function. See toil.job.FunctionWrappingJob for reserved keyword arguments used to specify resource requirements. Returns The new follow-on job that wraps fn. addChildJobFn(fn: Callable, *args, **kwargs) -> toil.job.FunctionWrappingJob Add a job function as a child job. See toil.job.JobFunctionWrappingJob for a definition of a job function. Parameters fn -- Job function to be run as a child job with *args and **kwargs as arguments to this function. See toil.job.JobFunctionWrappingJob for reserved keyword arguments used to specify resource requirements. Returns The new child job that wraps fn. addFollowOnJobFn(fn: Callable, *args, **kwargs) -> toil.job.FunctionWrappingJob Add a follow-on job function. See toil.job.JobFunctionWrappingJob for a definition of a job function. Parameters fn -- Job function to be run as a follow-on job with *args and **kwargs as arguments to this function. See toil.job.JobFunctionWrappingJob for reserved keyword arguments used to specify resource requirements. Returns The new follow-on job that wraps fn. property tempDir: str Shortcut to calling job.fileStore.getLocalTempDir(). Temp dir is created on first call and will be returned for first and future calls :return: Path to tempDir. See job.fileStore.getLocalTempDir log(text: str, level=20) -> None Convenience wrapper for fileStore.logToMaster(). static wrapFn(fn, *args, **kwargs) Makes a Job out of a function. Convenience function for constructor of toil.job.FunctionWrappingJob. Parameters fn -- Function to be run with *args and **kwargs as arguments. See toil.job.JobFunctionWrappingJob for reserved keyword arguments used to specify resource requirements. Returns The new function that wraps fn. Return type toil.job.FunctionWrappingJob static wrapJobFn(fn, *args, **kwargs) Makes a Job out of a job function. Convenience function for constructor of toil.job.JobFunctionWrappingJob. Parameters fn -- Job function to be run with *args and **kwargs as arguments. See toil.job.JobFunctionWrappingJob for reserved keyword arguments used to specify resource requirements. Returns The new job function that wraps fn. Return type toil.job.JobFunctionWrappingJob encapsulate(name=None) Encapsulates the job, see toil.job.EncapsulatedJob. Convenience function for constructor of toil.job.EncapsulatedJob. Parameters name (str) -- Human-readable name for the encapsulated job. Returns an encapsulated version of this job. Return type toil.job.EncapsulatedJob rv(*path) -> Any Create a promise (toil.job.Promise). The "promise" representing a return value of the job's run method, or, in case of a function-wrapping job, the wrapped function's return value. Parameters path ((Any)) -- Optional path for selecting a component of the promised return value. If absent or empty, the entire return value will be used. Otherwise, the first element of the path is used to select an individual item of the return value. For that to work, the return value must be a list, dictionary or of any other type implementing the __getitem__() magic method. If the selected item is yet another composite value, the second element of the path can be used to select an item from it, and so on. For example, if the return value is [6,{'a':42}], .rv(0) would select 6 , rv(1) would select {'a':3} while rv(1,'a') would select 3. To select a slice from a return value that is slicable, e.g. tuple or list, the path element should be a slice object. For example, assuming that the return value is [6, 7, 8, 9] then .rv(slice(1, 3)) would select [7, 8]. Note that slicing really only makes sense at the end of path. Returns A promise representing the return value of this jobs toil.job.Job.run() method. Return type toil.job.Promise prepareForPromiseRegistration(jobStore) Ensure that a promise by this job (the promissor) can register with the promissor when another job referring to the promise (the promissee) is being serialized. The promissee holds the reference to the promise (usually as part of the the job arguments) and when it is being pickled, so will the promises it refers to. Pickling a promise triggers it to be registered with the promissor. Returns checkJobGraphForDeadlocks() Ensures that a graph of Jobs (that hasn't yet been saved to the JobStore) doesn't contain any pathological relationships between jobs that would result in deadlocks if we tried to run the jobs. See toil.job.Job.checkJobGraphConnected(), toil.job.Job.checkJobGraphAcyclic() and toil.job.Job.checkNewCheckpointsAreLeafVertices() for more info. Raises toil.job.JobGraphDeadlockException -- if the job graph is cyclic, contains multiple roots or contains checkpoint jobs that are not leaf vertices when defined (see toil.job.Job.checkNewCheckpointsAreLeaves()). getRootJobs() -> Set[toil.job.Job] Returns the set of root job objects that contain this job. A root job is a job with no predecessors (i.e. which are not children, follow-ons, or services). Only deals with jobs created here, rather than loaded from the job store. checkJobGraphConnected() Raises toil.job.JobGraphDeadlockException -- if toil.job.Job.getRootJobs() does not contain exactly one root job. As execution always starts from one root job, having multiple root jobs will cause a deadlock to occur. Only deals with jobs created here, rather than loaded from the job store. checkJobGraphAcylic() Raises toil.job.JobGraphDeadlockException -- if the connected component of jobs containing this job contains any cycles of child/followOn dependencies in the augmented job graph (see below). Such cycles are not allowed in valid job graphs. A follow-on edge (A, B) between two jobs A and B is equivalent to adding a child edge to B from (1) A, (2) from each child of A, and (3) from the successors of each child of A. We call each such edge an edge an "implied" edge. The augmented job graph is a job graph including all the implied edges. For a job graph G = (V, E) the algorithm is O(|V|^2). It is O(|V| + |E|) for a graph with no follow-ons. The former follow-on case could be improved! Only deals with jobs created here, rather than loaded from the job store. checkNewCheckpointsAreLeafVertices() A checkpoint job is a job that is restarted if either it fails, or if any of its successors completely fails, exhausting their retries. A job is a leaf it is has no successors. A checkpoint job must be a leaf when initially added to the job graph. When its run method is invoked it can then create direct successors. This restriction is made to simplify implementation. Only works on connected components of jobs not yet added to the JobStore. Raises toil.job.JobGraphDeadlockException -- if there exists a job being added to the graph for which checkpoint=True and which is not a leaf. defer(function, *args, **kwargs) Register a deferred function, i.e. a callable that will be invoked after the current attempt at running this job concludes. A job attempt is said to conclude when the job function (or the toil.job.Job.run() method for class-based jobs) returns, raises an exception or after the process running it terminates abnormally. A deferred function will be called on the node that attempted to run the job, even if a subsequent attempt is made on another node. A deferred function should be idempotent because it may be called multiple times on the same node or even in the same process. More than one deferred function may be registered per job attempt by calling this method repeatedly with different arguments. If the same function is registered twice with the same or different arguments, it will be called twice per job attempt. Examples for deferred functions are ones that handle cleanup of resources external to Toil, like Docker containers, files outside the work directory, etc. Parameters · function (callable) -- The function to be called after this job concludes. · args (list) -- The arguments to the function · kwargs (dict) -- The keyword arguments to the function getTopologicalOrderingOfJobs() Returns a list of jobs such that for all pairs of indices i, j for which i < j, the job at index i can be run before the job at index j. Only considers jobs in this job's subgraph that are newly added, not loaded from the job store. Ignores service jobs. Return type list[Job] saveBody(jobStore) Save the execution data for just this job to the JobStore, and fill in the JobDescription with the information needed to retrieve it. The Job's JobDescription must have already had a real jobStoreID assigned to it. Does not save the JobDescription. Parameters jobStore (toil.jobStores.abstractJobStore.AbstractJobStore) -- The job store to save the job body into. saveAsRootJob(jobStore) Save this job to the given jobStore as the root job of the workflow. Parameters jobStore (toil.jobStores.abstractJobStore.AbstractJobStore) -- Returns the JobDescription describing this job. classmethod loadJob(jobStore: AbstractJobStore, jobDescription: toil.job.JobDescription) -> Job Retrieves a toil.job.Job instance from a JobStore Parameters · jobStore -- The job store. · jobDescription -- the JobDescription of the job to retrieve. Returns The job referenced by the JobDescription. JobDescription The class used to store all the information that the Toil Leader ever needs to know about a Job. class toil.job.JobDescription(requirements: Mapping[str, Union[int, str, bool]], jobName: str, unitName: str = '', displayName: str = '', command: Optional[str] = None) Stores all the information that the Toil Leader ever needs to know about a Job. (requirements information, dependency information, commands to issue, etc.) Can be obtained from an actual (i.e. executable) Job object, and can be used to obtain the Job object from the JobStore. Never contains other Jobs or JobDescriptions: all reference is by ID. Subclassed into variants for checkpoint jobs and service jobs that have their specific parameters. __init__(requirements: Mapping[str, Union[int, str, bool]], jobName: str, unitName: str = '', displayName: str = '', command: Optional[str] = None) -> None Create a new JobDescription. Parameters · requirements -- Dict from string to number, string, or bool describing the resource requirements of the job. 'cores', 'memory', 'disk', and 'preemptable' fields, if set, are parsed and broken out into properties. If unset, the relevant property will be unspecified, and will be pulled from the assigned Config object if queried (see toil.job.Requirer.assignConfig()). · jobName -- Name of the kind of job this is. May be used in job store IDs and logging. Also used to let the cluster scaler learn a model for how long the job will take. Ought to be the job class's name if no real user-defined name is available. · unitName -- Name of this instance of this kind of job. May appear with jobName in logging. · displayName -- A human-readable name to identify this particular job instance. Ought to be the job class's name if no real user-defined name is available. serviceHostIDsInBatches() -> Iterator[List[str]] Find all batches of service host job IDs that can be started at the same time. (in the order they need to start in) successorsAndServiceHosts() -> Iterator[str] Get an iterator over all child, follow-on, and service job IDs. allSuccessors() Get an iterator over all child and follow-on job IDs. property services Get a collection of the IDs of service host jobs for this job, in arbitrary order. Will be empty if the job has no unfinished services. nextSuccessors() -> List[str] Return the collection of job IDs for the successors of this job that are ready to run. If those jobs have multiple predecessor relationships, they may still be blocked on other jobs. Returns None when at the final phase (all successors done), and an empty collection if there are more phases but they can't be entered yet (e.g. because we are waiting for the job itself to run). property stack: Tuple[Tuple[str, ...], ...] Get IDs of successors that need to run still. Batches of successors are in reverse order of the order they need to run in. Some successors in each batch may have already been finished. Batches may be empty. Exists so that code that used the old stack list immutably can work still. New development should use nextSuccessors(), and all mutations should use filterSuccessors() (which automatically removes completed phases). Returns Batches of successors that still need to run, in reverse order. An empty batch may exist under a non-empty batch, or at the top when the job itself is not done. Return type tuple(tuple(str)) filterSuccessors(predicate: Callable[[str], bool]) -> None Keep only successor jobs for which the given predicate function approves. The predicate function is called with the job's ID. Treats all other successors as complete and forgets them. filterServiceHosts(predicate: Callable[[str], bool]) -> None Keep only services for which the given predicate approves. The predicate function is called with the service host job's ID. Treats all other services as complete and forgets them. clearSuccessorsAndServiceHosts() -> None Remove all references to child, follow-on, and associated service jobs. replace(other: toil.job.JobDescription) -> None Take on the ID of another JobDescription, retaining our own state and type. When updated in the JobStore, we will save over the other JobDescription. Useful for chaining jobs: the chained-to job can replace the parent job. Merges cleanup state from the job being replaced into this one. Parameters other -- Job description to replace. addChild(childID: str) -> None Make the job with the given ID a child of the described job. addFollowOn(followOnID: str) -> None Make the job with the given ID a follow-on of the described job. addServiceHostJob(serviceID, parentServiceID=None) Make the ServiceHostJob with the given ID a service of the described job. If a parent ServiceHostJob ID is given, that parent service will be started first, and must have already been added. hasChild(childID: str) -> bool Return True if the job with the given ID is a child of the described job. hasFollowOn(followOnID: str) -> bool Test if the job with the given ID is a follow-on of the described job. hasServiceHostJob(serviceID) -> bool Test if the ServiceHostJob is a service of the described job. renameReferences(renames: Dict[toil.job.TemporaryID, str]) -> None Apply the given dict of ID renames to all references to jobs. Does not modify our own ID or those of finished predecessors. IDs not present in the renames dict are left as-is. Parameters renames -- Rename operations to apply. addPredecessor() -> None Notify the JobDescription that a predecessor has been added to its Job. onRegistration(jobStore: AbstractJobStore) -> None Called by the Job saving logic when this JobDescription meets the JobStore and has its ID assigned. Overridden to perform setup work (like hooking up flag files for service jobs) that requires the JobStore. Parameters jobStore -- The job store we are being placed into setupJobAfterFailure(exitStatus=None) Reduce the remainingTryCount if greater than zero and set the memory to be at least as big as the default memory (in case of exhaustion of memory, which is common). Requires a configuration to have been assigned (see toil.job.Requirer.assignConfig()). Parameters exitReason (toil.batchSystems.abstractBatchSystem.BatchJobExitReason) -- The configuration for the current workflow run. getLogFileHandle(jobStore) Returns a context manager that yields a file handle to the log file. Assumes logJobStoreFileID is set. property remainingTryCount The try count set on the JobDescription, or the default based on the retry count from the config if none is set. clearRemainingTryCount() -> bool Clear remainingTryCount and set it back to its default value. Returns True if a modification to the JobDescription was made, and False otherwise. pre_update_hook() -> None Called by the job store before pickling and saving a created or updated version of a job.
JOB.RUNNER API
The Runner contains the methods needed to configure and start a Toil run. class Job.Runner Used to setup and run Toil workflow. static getDefaultArgumentParser() -> argparse.ArgumentParser Get argument parser with added toil workflow options. Returns The argument parser used by a toil workflow with added Toil options. Return type argparse.ArgumentParser static getDefaultOptions(jobStore: str) -> argparse.Namespace Get default options for a toil workflow. Parameters jobStore (string) -- A string describing the jobStore for the workflow. Returns The options used by a toil workflow. Return type argparse.ArgumentParser values object static addToilOptions(parser) Adds the default toil options to an optparse or argparse parser object. Parameters parser (optparse.OptionParser or argparse.ArgumentParser) -- Options object to add toil options to. static startToil(job, options) Run the toil workflow using the given options. Deprecated by toil.common.Toil.start. (see Job.Runner.getDefaultOptions and Job.Runner.addToilOptions) starting with this job. :param toil.job.Job job: root job of the workflow :raises: toil.leader.FailedJobsException if at the end of function their remain failed jobs. :return: The return value of the root job's run function. :rtype: Any
JOB.FILESTORE API
The AbstractFileStore is an abstraction of a Toil run's shared storage. class toil.fileStores.abstractFileStore.AbstractFileStore(jobStore: toil.jobStores.abstractJobStore.AbstractJobStore, jobDesc: toil.job.JobDescription, localTempDir: str, waitForPreviousCommit: Callable[[], Any]) Interface used to allow user code run by Toil to read and write files. Also provides the interface to other Toil facilities used by user code, including: · normal (non-real-time) logging · finding the correct temporary directory for scratch work · importing and exporting files into and out of the workflow Stores user files in the jobStore, but keeps them separate from actual jobs. May implement caching. Passed as argument to the toil.job.Job.run() method. Access to files is only permitted inside the context manager provided by toil.fileStores.abstractFileStore.AbstractFileStore.open(). Also responsible for committing completed jobs back to the job store with an update operation, and allowing that commit operation to be waited for. __init__(jobStore: toil.jobStores.abstractJobStore.AbstractJobStore, jobDesc: toil.job.JobDescription, localTempDir: str, waitForPreviousCommit: Callable[[], Any]) -> None Create a new file store object. Parameters · jobStore -- the job store in use for the current Toil run. · jobDesc -- the JobDescription object for the currently running job. · localTempDir -- the per-worker local temporary directory, under which per-job directories will be created. Assumed to be inside the workflow directory, which is assumed to be inside the work directory. · waitForPreviousCommit -- the waitForCommit method of the previous job's file store, when jobs are running in sequence on the same worker. Used to prevent this file store's startCommit and the previous job's startCommit methods from running at the same time and racing. If they did race, it might be possible for the later job to be fully marked as completed in the job store before the eralier job was. static createFileStore(jobStore: toil.jobStores.abstractJobStore.AbstractJobStore, jobDesc: toil.job.JobDescription, localTempDir: str, waitForPreviousCommit: Callable[[], Any], caching: bool) -> Union[NonCachingFileStore, CachingFileStore] Create a concreate FileStore. static shutdownFileStore(workflowDir: str, workflowID: str) -> None Carry out any necessary filestore-specific cleanup. This is a destructive operation and it is important to ensure that there are no other running processes on the system that are modifying or using the file store for this workflow. This is the intended to be the last call to the file store in a Toil run, called by the batch system cleanup function upon batch system shutdown. Parameters · workflowDir -- The path to the cache directory · workflowID -- The workflow ID for this invocation of the workflow open(job: toil.job.Job) -> Generator[None, None, None] Create the context manager around tasks prior and after a job has been run. File operations are only permitted inside the context manager. Implementations must only yield from within with super().open(job):. Parameters job -- The job instance of the toil job to run. getLocalTempDir() -> str Get a new local temporary directory in which to write files. The directory will only persist for the duration of the job. Returns The absolute path to a new local temporary directory. This directory will exist for the duration of the job only, and is guaranteed to be deleted once the job terminates, removing all files it contains recursively. getLocalTempFile() -> str Get a new local temporary file that will persist for the duration of the job. Returns The absolute path to a local temporary file. This file will exist for the duration of the job only, and is guaranteed to be deleted once the job terminates. getLocalTempFileName() -> str Get a valid name for a new local file. Don't actually create a file at the path. Returns Path to valid file abstract writeGlobalFile(localFileName: str, cleanup: bool = False) -> toil.fileStores.FileID Upload a file (as a path) to the job store. If the file is in a FileStore-managed temporary directory (i.e. from toil.fileStores.abstractFileStore.AbstractFileStore.getLocalTempDir()), it will become a local copy of the file, eligible for deletion by toil.fileStores.abstractFileStore.AbstractFileStore.deleteLocalFile(). If an executable file on the local filesystem is uploaded, its executability will be preserved when it is downloaded again. Parameters · localFileName -- The path to the local file to upload. The last path component (basename of the file) will remain associated with the file in the file store, if supported by the backing JobStore, so that the file can be searched for by name or name glob. · cleanup -- if True then the copy of the global file will be deleted once the job and all its successors have completed running. If not the global file must be deleted manually. Returns an ID that can be used to retrieve the file. writeGlobalFileStream(cleanup: bool = False, basename: Optional[str] = None, encoding: Optional[str] = None, errors: Optional[str] = None) -> Iterator[Tuple[toil.lib.io.WriteWatchingStream, toil.fileStores.FileID]] Similar to writeGlobalFile, but allows the writing of a stream to the job store. The yielded file handle does not need to and should not be closed explicitly. Parameters · encoding -- The name of the encoding used to decode the file. Encodings are the same as for decode(). Defaults to None which represents binary mode. · errors -- Specifies how encoding errors are to be handled. Errors are the same as for open(). Defaults to 'strict' when an encoding is specified. · cleanup -- is as in toil.fileStores.abstractFileStore.AbstractFileStore.writeGlobalFile(). · basename -- If supported by the backing JobStore, use the given file basename so that when searching the job store with a query matching that basename, the file will be detected. Returns A context manager yielding a tuple of 1) a file handle which can be written to and 2) the toil.fileStores.FileID of the resulting file in the job store. logAccess(fileStoreID: Union[toil.fileStores.FileID, str], destination: Optional[str] = None) -> None Record that the given file was read by the job. (to be announced if the job fails) If destination is not None, it gives the path that the file was downloaded to. Otherwise, assumes that the file was streamed. Must be called by readGlobalFile() and readGlobalFileStream() implementations. abstract readGlobalFile(fileStoreID: str, userPath: Optional[str] = None, cache: bool = True, mutable: bool = False, symlink: bool = False) -> str Make the file associated with fileStoreID available locally. If mutable is True, then a copy of the file will be created locally so that the original is not modified and does not change the file for other jobs. If mutable is False, then a link can be created to the file, saving disk resources. The file that is downloaded will be executable if and only if it was originally uploaded from an executable file on the local filesystem. If a user path is specified, it is used as the destination. If a user path isn't specified, the file is stored in the local temp directory with an encoded name. The destination file must not be deleted by the user; it can only be deleted through deleteLocalFile. Implementations must call logAccess() to report the download. Parameters · fileStoreID -- job store id for the file · userPath -- a path to the name of file to which the global file will be copied or hard-linked (see below). · cache -- Described in toil.fileStores.CachingFileStore.readGlobalFile() · mutable -- Described in toil.fileStores.CachingFileStore.readGlobalFile() Returns An absolute path to a local, temporary copy of the file keyed by fileStoreID. abstract readGlobalFileStream(fileStoreID: str, encoding: Optional[str] = None, errors: Optional[str] = None) -> ContextManager[Union[BinaryIO, TextIO]] Read a stream from the job store; similar to readGlobalFile. The yielded file handle does not need to and should not be closed explicitly. Parameters · encoding -- the name of the encoding used to decode the file. Encodings are the same as for decode(). Defaults to None which represents binary mode. · errors -- an optional string that specifies how encoding errors are to be handled. Errors are the same as for open(). Defaults to 'strict' when an encoding is specified. Implementations must call logAccess() to report the download. Returns a context manager yielding a file handle which can be read from. getGlobalFileSize(fileStoreID: Union[toil.fileStores.FileID, str]) -> int Get the size of the file pointed to by the given ID, in bytes. If a FileID or something else with a non-None 'size' field, gets that. Otherwise, asks the job store to poll the file's size. Note that the job store may overestimate the file's size, for example if it is encrypted and had to be augmented with an IV or other encryption framing. Parameters fileStoreID -- File ID for the file Returns File's size in bytes, as stored in the job store abstract deleteLocalFile(fileStoreID: Union[toil.fileStores.FileID, str]) -> None Delete local copies of files associated with the provided job store ID. Raises an OSError with an errno of errno.ENOENT if no such local copies exist. Thus, cannot be called multiple times in succession. The files deleted are all those previously read from this file ID via readGlobalFile by the current job into the job's file-store-provided temp directory, plus the file that was written to create the given file ID, if it was written by the current job from the job's file-store-provided temp directory. Parameters fileStoreID -- File Store ID of the file to be deleted. abstract deleteGlobalFile(fileStoreID: Union[toil.fileStores.FileID, str]) -> None Delete local files and then permanently deletes them from the job store. To ensure that the job can be restarted if necessary, the delete will not happen until after the job's run method has completed. Parameters fileStoreID -- the File Store ID of the file to be deleted. logToMaster(text: str, level: int = 20) -> None Send a logging message to the leader. The message will also be logged by the worker at the same level. Parameters · text -- The string to log. · level -- The logging level. abstract startCommit(jobState: bool = False) -> None Update the status of the job on the disk. May start an asynchronous process. Call waitForCommit() to wait on that process. Parameters jobState -- If True, commit the state of the FileStore's job, and file deletes. Otherwise, commit only file creates/updates. abstract waitForCommit() -> bool Blocks while startCommit is running. This function is called by this job's successor to ensure that it does not begin modifying the job store until after this job has finished doing so. Might be called when startCommit is never called on a particular instance, in which case it does not block. Returns Always returns True abstract classmethod shutdown(dir_: str) -> None Shutdown the filestore on this node. This is intended to be called on batch system shutdown. Parameters dir -- The implementation-specific directory containing the required information for shutting down the file store and removing all its state and all job local temp directories from the node. class toil.fileStores.FileID(fileStoreID: str, *args: Any) A small wrapper around Python's builtin string class. It is used to represent a file's ID in the file store, and has a size attribute that is the file's size in bytes. This object is returned by importFile and writeGlobalFile. Calls into the file store can use bare strings; size will be queried from the job store if unavailable in the ID. __init__(fileStoreID: str, size: int, executable: bool = False) -> None pack() -> str Pack the FileID into a string so it can be passed through external code. classmethod unpack(packedFileStoreID: str) -> toil.fileStores.FileID Unpack the result of pack() into a FileID object.
BATCH SYSTEM API
The batch system interface is used by Toil to abstract over different ways of running batches of jobs, for example Slurm, GridEngine, Mesos, Parasol and a single node. The toil.batchSystems.abstractBatchSystem.AbstractBatchSystem API is implemented to run jobs using a given job management system, e.g. Mesos. Batch System Enivronmental Variables Environmental variables allow passing of scheduler specific parameters. For SLURM: export TOIL_SLURM_ARGS="-t 1:00:00 -q fatq" For TORQUE there are two environment variables - one for everything but the resource requirements, and another - for resources requirements (without the -l prefix): export TOIL_TORQUE_ARGS="-q fatq" export TOIL_TORQUE_REQS="walltime=1:00:00" For GridEngine (SGE, UGE), there is an additional environmental variable to define the parallel environment for running multicore jobs: export TOIL_GRIDENGINE_PE='smp' export TOIL_GRIDENGINE_ARGS='-q batch.q' For HTCondor, additional parameters can be included in the submit file passed to condor_submit: export TOIL_HTCONDOR_PARAMS='requirements = TARGET.has_sse4_2 == true; accounting_group = test' The environment variable is parsed as a semicolon-separated string of parameter = value pairs. Batch System API class toil.batchSystems.abstractBatchSystem.AbstractBatchSystem An abstract (as far as Python currently allows) base class to represent the interface the batch system must provide to Toil. abstract classmethod supportsAutoDeployment() -> bool Whether this batch system supports auto-deployment of the user script itself. If it does, the setUserScript() can be invoked to set the resource object representing the user script. Note to implementors: If your implementation returns True here, it should also override abstract classmethod supportsWorkerCleanup() -> bool Indicates whether this batch system invokes BatchSystemSupport.workerCleanup() after the last job for a particular workflow invocation finishes. Note that the term worker refers to an entire node, not just a worker process. A worker process may run more than one job sequentially, and more than one concurrent worker process may exist on a worker node, for the same workflow. The batch system is said to shut down after the last worker process terminates. setUserScript(userScript: toil.resource.Resource) -> None Set the user script for this workflow. This method must be called before the first job is issued to this batch system, and only if supportsAutoDeployment() returns True, otherwise it will raise an exception. Parameters userScript -- the resource object representing the user script or module and the modules it depends on. abstract issueBatchJob(jobDesc: toil.job.JobDescription, job_environment: Optional[Dict[str, str]] = None) -> int Issues a job with the specified command to the batch system and returns a unique jobID. :param jobDesc a toil.job.JobDescription :param job_environment: a collection of job-specific environment variables to be set on the worker. Returns a unique jobID that can be used to reference the newly issued job abstract killBatchJobs(jobIDs: List[int]) -> None Kills the given job IDs. After returning, the killed jobs will not appear in the results of getRunningBatchJobIDs. The killed job will not be returned from getUpdatedBatchJob. Parameters jobIDs -- list of IDs of jobs to kill abstract getIssuedBatchJobIDs() -> List[int] Gets all currently issued jobs Returns A list of jobs (as jobIDs) currently issued (may be running, or may be waiting to be run). Despite the result being a list, the ordering should not be depended upon. abstract getRunningBatchJobIDs() -> Dict[int, float] Gets a map of jobs as jobIDs that are currently running (not just waiting) and how long they have been running, in seconds. Returns dictionary with currently running jobID keys and how many seconds they have been running as the value abstract getUpdatedBatchJob(maxWait: int) -> Optional[toil.batchSystems.abstractBatchSystem.UpdatedBatchJobInfo] Returns information about job that has updated its status (i.e. ceased running, either successfully or with an error). Each such job will be returned exactly once. Does not return info for jobs killed by killBatchJobs, although they may cause None to be returned earlier than maxWait. Parameters maxWait -- the number of seconds to block, waiting for a result Returns If a result is available, returns UpdatedBatchJobInfo. Otherwise it returns None. wallTime is the number of seconds (a strictly positive float) in wall-clock time the job ran for, or None if this batch system does not support tracking wall time. getSchedulingStatusMessage() -> Optional[str] Get a log message fragment for the user about anything that might be going wrong in the batch system, if available. If no useful message is available, return None. This can be used to report what resource is the limiting factor when scheduling jobs, for example. If the leader thinks the workflow is stuck, the message can be displayed to the user to help them diagnose why it might be stuck. Returns User-directed message about scheduling state. abstract shutdown() -> None Called at the completion of a toil invocation. Should cleanly terminate all worker threads. setEnv(name: str, value: Optional[str] = None) -> None Set an environment variable for the worker process before it is launched. The worker process will typically inherit the environment of the machine it is running on but this method makes it possible to override specific variables in that inherited environment before the worker is launched. Note that this mechanism is different to the one used by the worker internally to set up the environment of a job. A call to this method affects all jobs issued after this method returns. Note to implementors: This means that you would typically need to copy the variables before enqueuing a job. If no value is provided it will be looked up from the current environment. classmethod add_options(parser: Union[argparse.ArgumentParser, argparse._ArgumentGroup]) -> None If this batch system provides any command line options, add them to the given parser. classmethod setOptions(setOption: Callable[[str, Optional[Callable[[Any], toil.batchSystems.abstractBatchSystem.OptionType]], Optional[Callable[[toil.batchSystems.abstractBatchSystem.OptionType], None]], Optional[toil.batchSystems.abstractBatchSystem.OptionType], Optional[List[str]]], None]) -> None Process command line or configuration options relevant to this batch system. Parameters setOption -- A function with signature setOption(option_name, parsing_function=None, check_function=None, default=None, env=None) returning nothing, used to update run configuration as a side effect. getWorkerContexts() -> List[ContextManager[Any]] Get a list of picklable context manager objects to wrap worker work in, in order. Can be used to ask the Toil worker to do things in-process (such as configuring environment variables, hot-deploying user scripts, or cleaning up a node) that would otherwise require a wrapping "executor" process.
JOB.SERVICE API
The Service class allows databases and servers to be spawned within a Toil workflow. class Job.Service(memory=None, cores=None, disk=None, preemptable=None, unitName=None) Abstract class used to define the interface to a service. Should be subclassed by the user to define services. Is not executed as a job; runs within a ServiceHostJob. __init__(memory=None, cores=None, disk=None, preemptable=None, unitName=None) Memory, core and disk requirements are specified identically to as in toil.job.Job.__init__(). abstract start(job) Start the service. Parameters job (toil.job.Job) -- The underlying host job that the service is being run in. Can be used to register deferred functions, or to access the fileStore for creating temporary files. Returns An object describing how to access the service. The object must be pickleable and will be used by jobs to access the service (see toil.job.Job.addService()). abstract stop(job) Stops the service. Function can block until complete. Parameters job (toil.job.Job) -- The underlying host job that the service is being run in. Can be used to register deferred functions, or to access the fileStore for creating temporary files. check() Checks the service is still running. Raises exceptions.RuntimeError -- If the service failed, this will cause the service job to be labeled failed. Returns True if the service is still running, else False. If False then the service job will be terminated, and considered a success. Important point: if the service job exits due to a failure, it should raise a RuntimeError, not return False!
EXCEPTIONS API
Toil specific exceptions. exception toil.job.JobException(message: str) General job exception. __init__(message: str) -> None exception toil.job.JobGraphDeadlockException(string) An exception raised in the event that a workflow contains an unresolvable dependency, such as a cycle. See toil.job.Job.checkJobGraphForDeadlocks(). __init__(string) exception toil.jobStores.abstractJobStore.ConcurrentFileModificationException(jobStoreFileID: toil.fileStores.FileID) Indicates that the file was attempted to be modified by multiple processes at once. __init__(jobStoreFileID: toil.fileStores.FileID) Parameters jobStoreFileID -- the ID of the file that was modified by multiple workers or processes concurrently exception toil.jobStores.abstractJobStore.JobStoreExistsException(locator: str) Indicates that the specified job store already exists. __init__(locator: str) Parameters locator (str) -- The location of the job store exception toil.jobStores.abstractJobStore.NoSuchFileException(jobStoreFileID: toil.fileStores.FileID, customName: Optional[str] = None, *extra: Any) Indicates that the specified file does not exist. __init__(jobStoreFileID: toil.fileStores.FileID, customName: Optional[str] = None, *extra: Any) Parameters · jobStoreFileID -- the ID of the file that was mistakenly assumed to exist · customName -- optionally, an alternate name for the nonexistent file · extra (list) -- optional extra information to add to the error message exception toil.jobStores.abstractJobStore.NoSuchJobException(jobStoreID: toil.fileStores.FileID) Indicates that the specified job does not exist. __init__(jobStoreID: toil.fileStores.FileID) Parameters jobStoreID (str) -- the jobStoreID that was mistakenly assumed to exist exception toil.jobStores.abstractJobStore.NoSuchJobStoreException(locator: str) Indicates that the specified job store does not exist. __init__(locator: str) Parameters locator (str) -- The location of the job store
RUNNING TESTS
Test make targets, invoked as $ make <target>, subject to which environment variables are set (see Running Integration Tests). ┌───────────────────────┬──────────────────────────────────┐ │TARGET │ DESCRIPTION │ ├───────────────────────┼──────────────────────────────────┤ │test │ Invokes all tests. │ ├───────────────────────┼──────────────────────────────────┤ │integration_test │ Invokes only the integration │ │ │ tests. │ ├───────────────────────┼──────────────────────────────────┤ │test_offline │ Skips building the Docker │ │ │ appliance and only invokes tests │ │ │ that have no docker │ │ │ dependencies. │ ├───────────────────────┼──────────────────────────────────┤ │integration_test_local │ Makes integration tests easier │ │ │ to debug locally by running the │ │ │ integration tests serially and │ │ │ doesn't redirect output. This │ │ │ makes it appears on the terminal │ │ │ as expected. │ └───────────────────────┴──────────────────────────────────┘ Before running tests for the first time, initialize your virtual environment following the steps in buildFromSource. Run all tests (including slow tests): $ make test Run only quick tests (as of Jul 25, 2018, this was ~ 20 minutes): $ export TOIL_TEST_QUICK=True; make test Run an individual test with: $ make test tests=src/toil/test/sort/sortTest.py::SortTest::testSort The default value for tests is "src" which includes all tests in the src/ subdirectory of the project root. Tests that require a particular feature will be skipped implicitly. If you want to explicitly skip tests that depend on a currently installed feature, use $ make test tests="-m 'not aws' src" This will run only the tests that don't depend on the aws extra, even if that extra is currently installed. Note the distinction between the terms feature and extra. Every extra is a feature but there are features that are not extras, such as the gridengine and parasol features. To skip tests involving both the parasol feature and the aws extra, use the following: $ make test tests="-m 'not aws and not parasol' src" Running Tests with pytest Often it is simpler to use pytest directly, instead of calling the make wrapper. This usually works as expected, but some tests need some manual preparation. To run a specific test with pytest, use the following: python -m pytest src/toil/test/sort/sortTest.py::SortTest::testSort For more information, see the pytest documentation. Running Integration Tests These tests are generally only run using in our CI workflow due to their resource requirements and cost. However, they can be made available for local testing: · Running tests that make use of Docker (e.g. autoscaling tests and Docker tests) require an appliance image to be hosted. First, make sure you have gone through the set up found in Using Docker with Quay. Then to build and host the appliance image run the make target push_docker. $ make push_docker · Running integration tests require activation via an environment variable as well as exporting information relevant to the desired tests. Enable the integration tests: $ export TOIL_TEST_INTEGRATIVE=True · Finally, set the environment variables for keyname and desired zone: $ export TOIL_X_KEYNAME=[Your Keyname] $ export TOIL_X_ZONE=[Desired Zone] Where X is one of our currently supported cloud providers (GCE, AWS). · See the above sections for guidance on running tests. Test Environment Variables ┌──────────────────────┬──────────────────────────────────┐ │TOIL_TEST_TEMP │ An absolute path to a directory │ │ │ where Toil tests will write │ │ │ their temporary files. Defaults │ │ │ to the system's standard │ │ │ temporary directory. │ ├──────────────────────┼──────────────────────────────────┤ │TOIL_TEST_INTEGRATIVE │ If True, this allows the │ │ │ integration tests to run. Only │ │ │ valid when running the tests │ │ │ from the source directory via │ │ │ make test or make test_parallel. │ ├──────────────────────┼──────────────────────────────────┤ │TOIL_AWS_KEYNAME │ An AWS keyname (see prepareAWS), │ │ │ which is required to run the AWS │ │ │ tests. │ ├──────────────────────┼──────────────────────────────────┤ │TOIL_GOOGLE_PROJECTID │ A Google Cloud account projectID │ │ │ (see runningGCE), which is │ │ │ required to to run the Google │ │ │ Cloud tests. │ ├──────────────────────┼──────────────────────────────────┤ │TOIL_TEST_QUICK │ If True, long running tests are │ │ │ skipped. │ └──────────────────────┴──────────────────────────────────┘ Partial install and failing tests Some tests may fail with an ImportError if the required extras are not installed. Install Toil with all of the extras do prevent such errors. Using Docker with Quay Docker is needed for some of the tests. Follow the appropriate installation instructions for your system on their website to get started. When running make test you might still get the following error: $ make test Please set TOIL_DOCKER_REGISTRY, e.g. to quay.io/USER. To solve, make an account with Quay and specify it like so: $ TOIL_DOCKER_REGISTRY=quay.io/USER make test where USER is your Quay username. For convenience you may want to add this variable to your bashrc by running $ echo 'export TOIL_DOCKER_REGISTRY=quay.io/USER' >> $HOME/.bashrc Running Mesos Tests If you're running Toil's Mesos tests, be sure to create the virtualenv with --system-site-packages to include the Mesos Python bindings. Verify this by activating the virtualenv and running pip list | grep mesos. On macOS, this may come up empty. To fix it, run the following: for i in /usr/local/lib/python2.7/site-packages/*mesos*; do ln -snf $i venv/lib/python2.7/site-packages/; done
DEVELOPING WITH DOCKER
To develop on features reliant on the Toil Appliance (the docker image toil uses for AWS autoscaling), you should consider setting up a personal registry on Quay or Docker Hub. Because the Toil Appliance images are tagged with the Git commit they are based on and because only commits on our master branch trigger an appliance build on Quay, as soon as a developer makes a commit or dirties the working copy they will no longer be able to rely on Toil to automatically detect the proper Toil Appliance image. Instead, developers wishing to test any appliance changes in autoscaling should build and push their own appliance image to a personal Docker registry. This is described in the next section. Making Your Own Toil Docker Image Note! Toil checks if the docker image specified by TOIL_APPLIANCE_SELF exists prior to launching by using the docker v2 schema. This should be valid for any major docker repository, but there is an option to override this if desired using the option: -\-forceDockerAppliance. Here is a general workflow (similar instructions apply when using Docker Hub): 1. Make some changes to the provisioner of your local version of Toil 2. Go to the location where you installed the Toil source code and run $ make docker to automatically build a docker image that can now be uploaded to your personal Quay account. If you have not installed Toil source code yet see buildFromSource. 3. If it's not already you will need Docker installed and need to log into Quay. Also you will want to make sure that your Quay account is public. 4. Set the environment variable TOIL_DOCKER_REGISTRY to your Quay account. If you find yourself doing this often you may want to add export TOIL_DOCKER_REGISTRY=quay.io/<MY_QUAY_USERNAME> to your .bashrc or equivalent. 5. Now you can run $ make push_docker which will upload the docker image to your Quay account. Take note of the image's tag for the next step. 6. Finally you will need to tell Toil from where to pull the Appliance image you've created (it uses the Toil release you have installed by default). To do this set the environment variable TOIL_APPLIANCE_SELF to the url of your image. For more info see envars. 7. Now you can launch your cluster! For more information see Autoscaling. Running a Cluster Locally The Toil Appliance container can also be useful as a test environment since it can simulate a Toil cluster locally. An important caveat for this is autoscaling, since autoscaling will only work on an EC2 instance and cannot (at this time) be run on a local machine. To spin up a local cluster, start by using the following Docker run command to launch a Toil leader container: docker run \ --entrypoint=mesos-master \ --net=host \ -d \ --name=leader \ --volume=/home/jobStoreParentDir:/jobStoreParentDir \ quay.io/ucsc_cgl/toil:3.6.0 \ --registry=in_memory \ --ip=127.0.0.1 \ --port=5050 \ --allocation_interval=500ms A couple notes on this command: the -d flag tells Docker to run in daemon mode so the container will run in the background. To verify that the container is running you can run docker ps to see all containers. If you want to run your own container rather than the official UCSC container you can simply replace the quay.io/ucsc_cgl/toil:3.6.0 parameter with your own container name. Also note that we are not mounting the job store directory itself, but rather the location where the job store will be written. Due to complications with running Docker on MacOS, I recommend only mounting directories within your home directory. The next command will launch the Toil worker container with similar parameters: docker run \ --entrypoint=mesos-slave \ --net=host \ -d \ --name=worker \ --volume=/home/jobStoreParentDir:/jobStoreParentDir \ quay.io/ucsc_cgl/toil:3.6.0 \ --work_dir=/var/lib/mesos \ --master=127.0.0.1:5050 \ --ip=127.0.0.1 \ —-attributes=preemptable:False \ --resources=cpus:2 Note here that we are specifying 2 CPUs and a non-preemptable worker. We can easily change either or both of these in a logical way. To change the number of cores we can change the 2 to whatever number you like, and to change the worker to be preemptable we change preemptable:False to preemptable:True. Also note that the same volume is mounted into the worker. This is needed since both the leader and worker write and read from the job store. Now that your cluster is running, you can run docker exec -it leader bash to get a shell in your leader 'node'. You can also replace the leader parameter with worker to get shell access in your worker. Docker-in-Docker issues If you want to run Docker inside this Docker cluster (Dockerized tools, perhaps), you should also mount in the Docker socket via -v /var/run/docker.sock:/var/run/docker.sock. This will give the Docker client inside the Toil Appliance access to the Docker engine on the host. Client/engine version mismatches have been known to cause issues, so we recommend using Docker version 1.12.3 on the host to be compatible with the Docker client installed in the Appliance. Finally, be careful where you write files inside the Toil Appliance - 'child' Docker containers launched in the Appliance will actually be siblings to the Appliance since the Docker engine is located on the host. This means that the 'child' container can only mount in files from the Appliance if the files are located in a directory that was originally mounted into the Appliance from the host - that way the files are accessible to the sibling container. Note: if Docker can't find the file/directory on the host it will silently fail and mount in an empty directory.
MAINTAINER'S GUIDELINES
In general, as developers and maintainers of the code, we adhere to the following guidelines: · We strive to never break the build on master. All development should be done on branches, in either the main Toil repository or in developers' forks. · Pull requests should be used for any and all changes (except truly trivial ones). · Pull requests should be in response to issues. If you find yourself making a pull request without an issue, you should create the issue first. Naming Conventions · Commit messages should be great. Most importantly, they must: · Have a short subject line. If in need of more space, drop down two lines and write a body to explain what is changing and why it has to change. · Write the subject line as a command: Destroy all humans, not All humans destroyed. · Reference the issue being fixed in a Github-parseable format, such as (resolves #1234) at the end of the subject line, or This will fix #1234. somewhere in the body. If no single commit on its own fixes the issue, the cross-reference must appear in the pull request title or body instead. · Branches in the main Toil repository must start with issues/, followed by the issue number (or numbers, separated by a dash), followed by a short, lowercase, hyphenated description of the change. (There can be many open pull requests with their associated branches at any given point in time and this convention ensures that we can easily identify branches.) Say there is an issue numbered #123 titled Foo does not work. The branch name would be issues/123-fix-foo and the title of the commit would be Fix foo in case of bar (resolves #123). Pull Requests · All pull requests must be reviewed by a person other than the request's author. Review the PR by following the reviewingPRs checklist. · Modified pull requests must be re-reviewed before merging. Note that Github does not enforce this! · Merge pull requests by following the mergingPRs checklist. · When merging a pull request, make sure to update the Draft Changelog on the Github wiki, which we will use to produce the changelog for the next release. The PR template tells you to do this, so don't forget. New entries should go at the bottom. · Pull requests will not be merged unless CI tests pass. Gitlab tests are only run on code in the main Toil repository on some branch, so it is the responsibility of the approving reviewer to make sure that pull requests from outside repositories are copied to branches in the main repository. This can be accomplished with (from a Toil clone): ./contrib/admin/test-pr theirusername their-branch issues/123-fix-description-here This must be repeated every time the PR submitter updates their PR, after checking to see that the update is not malicious. If there is no issue corresponding to the PR, after which the branch can be named, the reviewer of the PR should first create the issue. Developers who have push access to the main Toil repository are encouraged to make their pull requests from within the repository, to avoid this step. · Prefer using "Squash and marge" when merging pull requests to master especially when the PR contains a "single unit" of work (i.e. if one were to rewrite the PR from scratch with all the fixes included, they would have one commit for the entire PR). This makes the commit history on master more readable and easier to debug in case of a breakage. When squashing a PR from multiple authors, please add Co-authored-by to give credit to all contributing authors. See Issue #2816 for more details. Publishing a Release These are the steps to take to publish a Toil release: · Determine the release version X.Y.Z. This should follow semantic versioning; if user-workflow-breaking changes are made, X should be incremented, and Y and Z should be zero. If non-breaking changes are made but new functionality is added, X should remain the same as the last release, Y should be incremented, and Z should be zero. If only patches are released, X and Y should be the same as the last release and Z should be incremented. · If it does not exist already, create a release branch in the Toil repo named X.Y.x, where x is a literal lower-case "x". For patch releases, find the existing branch and make sure it is up to date with the patch commits that are to be released. They may be cherry-picked over from master. · On the release branch, edit version_template.py in the root of the repository. Find the line that looks like this (slightly different for patch releases): baseVersion = 'X.Y.0a1' Make it look like this instead: baseVersion = 'X.Y.Z' Commit your change to the branch. · Tag the current state of the release branch as releases/X.Y.Z. · Make the Github release here, referencing that tag. For a non-patch release, fill in the description with the changelog from the wiki page, which you should clear. For a patch release, just describe the patch. · For a non-patch release, set up the main branch so that development builds will declare themselves to be alpha versions of what the next release will probably be. Edit version_template.py in the root of the repository on the main branch to set baseVersion like this: baseVersion = 'X.Y+1.0a1' Make sure to replace X and Y+1 with actual numbers. Adding Retries to a Function See toil.lib.retry . retry() can be used to decorate any function based on the list of errors one wishes to retry on. This list of errors can contain normal Exception objects, and/or RetryCondition objects wrapping Exceptions to include additional conditions. For example, retrying on a one Exception (HTTPError): from requests import get from requests.exceptions import HTTPError @retry(errors=[HTTPError]) def update_my_wallpaper(): return get('https://www.deviantart.com/') Or: from requests import get from requests.exceptions import HTTPError @retry(errors=[HTTPError, ValueError]) def update_my_wallpaper(): return get('https://www.deviantart.com/') The examples above will retry for the default interval on any errors specified the "errors=" arg list. To retry on specifically 500/502/503/504 errors, you could specify an ErrorCondition object instead, for example: from requests import get from requests.exceptions import HTTPError @retry(errors=[ ErrorCondition( error=HTTPError, error_codes=[500, 502, 503, 504] )]) def update_my_wallpaper(): return requests.get('https://www.deviantart.com/') To retry on specifically errors containing the phrase "NotFound": from requests import get from requests.exceptions import HTTPError @retry(errors=[ ErrorCondition( error=HTTPError, error_message_must_include="NotFound" )]) def update_my_wallpaper(): return requests.get('https://www.deviantart.com/') To retry on all HTTPError errors EXCEPT an HTTPError containing the phrase "NotFound": from requests import get from requests.exceptions import HTTPError @retry(errors=[ HTTPError, ErrorCondition( error=HTTPError, error_message_must_include="NotFound", retry_on_this_condition=False )]) def update_my_wallpaper(): return requests.get('https://www.deviantart.com/') To retry on boto3's specific status errors, an example of the implementation is: import boto3 from botocore.exceptions import ClientError @retry(errors=[ ErrorCondition( error=ClientError, boto_error_codes=["BucketNotFound"] )]) def boto_bucket(bucket_name): boto_session = boto3.session.Session() s3_resource = boto_session.resource('s3') return s3_resource.Bucket(bucket_name) Any combination of these will also work, provided the codes are matched to the correct exceptions. A ValueError will not return a 404, for example. The retry function as a decorator should make retrying functions easier and clearer. It also encourages smaller independent functions, as opposed to lumping many different things that may need to be retried on different conditions in the same function. The ErrorCondition object tries to take some of the heavy lifting of writing specific retry conditions and boil it down to an API that covers all common use-cases without the user having to write any new bespoke functions. Use-cases covered currently: 1. Retrying on a normal error, like a KeyError. 2. Retrying on HTTP error codes (use ErrorCondition). 3. Retrying on boto's specific status errors, like "BucketNotFound" (use ErrorCondition). 4. Retrying when an error message contains a certain phrase (use ErrorCondition). 5. Explicitly NOT retrying on a condition (use ErrorCondition). If new functionality is needed, it's currently best practice in Toil to add functionality to the ErrorCondition itself rather than making a new custom retry method.
PULL REQUEST CHECKLISTS
This document contains checklists for dealing with PRs. More general PR information is available at PRs. Reviewing Pull Requests This checklist is to be kept in sync with the checklist in the pull request template. When reviewing a PR, do the following: · Make sure it is coming from issues/XXXX-fix-the-thing in the Toil repo, or from an external repo. · If it is coming from an external repo, make sure to pull it in for CI with: contrib/admin/test-pr otheruser theirbranchname issues/XXXX-fix-the-thing · If there is no associated issue, create one. · Read through the code changes. Make sure that it doesn't have: · Addition of trailing whitespace. · New variable or member names in camelCase that want to be in snake_case. · New functions without type hints. · New functions or classes without informative docstrings. · Changes to semantics not reflected in the relevant docstrings. · New or changed command line options for Toil workflows that are not reflected in docs/running/cliOptions.rst · New features without tests. · Comment on the lines of code where problems exist with a review comment. You can shift-click the line numbers in the diff to select multiple lines. · Finish the review with an overall description of your opinion. Merging Pull Requests This checklist is to be kept in sync with the checklist in the pull request template. When merging a PR, do the following: · Make sure the PR passes tests. · Make sure the PR has been reviewed since its last modification. If not, review it. · Merge with the Github Squash and merge feature. · If there are multiple authors' commits, add Co-authored-by to give credit to all contributing authors. · Copy its recommended changelog entry to the Draft Changelog. · Append the issue number in parentheses to the changelog entry.
TOIL ARCHITECTURE
The following diagram layouts out the software architecture of Toil. [image: Toil's architecture is composed of the leader, the job store, the worker processes, the batch system, the node provisioner, and the stats and logging monitor.] [image] Figure 1: The basic components of Toil's architecture..UNINDENT These components are described below: · the leader: The leader is responsible for deciding which jobs should be run. To do this it traverses the job graph. Currently this is a single threaded process, but we make aggressive steps to prevent it becoming a bottleneck (see Read-only Leader described below). · the job-store: Handles all files shared between the components. Files in the job-store are the means by which the state of the workflow is maintained. Each job is backed by a file in the job store, and atomic updates to this state are used to ensure the workflow can always be resumed upon failure. The job-store can also store all user files, allowing them to be shared between jobs. The job-store is defined by the AbstractJobStore class. Multiple implementations of this class allow Toil to support different back-end file stores, e.g.: S3, network file systems, Google file store, etc. · workers: The workers are temporary processes responsible for running jobs, one at a time per worker. Each worker process is invoked with a job argument that it is responsible for running. The worker monitors this job and reports back success or failure to the leader by editing the job's state in the file-store. If the job defines successor jobs the worker may choose to immediately run them (see Job Chaining below). · the batch-system: Responsible for scheduling the jobs given to it by the leader, creating a worker command for each job. The batch-system is defined by the AbstractBatchSystem class. Toil uses multiple existing batch systems to schedule jobs, including Apache Mesos, GridEngine and a multi-process single node implementation that allows workflows to be run without any of these frameworks. Toil can therefore fairly easily be made to run a workflow using an existing cluster. · the node provisioner: Creates worker nodes in which the batch system schedules workers. It is defined by the AbstractProvisioner class. · the statistics and logging monitor: Monitors logging and statistics produced by the workers and reports them. Uses the job-store to gather this information. Jobs and JobDescriptions As noted in jobBasics, a job is the atomic unit of work in a Toil workflow. User scripts inherit from the Job class to define units of work. These jobs are pickled and stored in the job-store by the leader, and are retrieved and un-pickled by the worker when they are scheduled to run. During scheduling, Toil does not work with the actual Job objects. Instead, JobDescription objects are used to store all the information that the Toil Leader ever needs to know about the Job. This includes requirements information, dependency information, commands to issue, etc. Internally, the JobDescription object is referenced by its jobStoreID, which is often not human readable. However, the Job and JobDescription objects contain several human-readable names that are useful for logging and identification: ┌────────────┬──────────────────────────────────┐ │jobName │ Name of the kind of job this is. │ │ │ This may be used in job store │ │ │ IDs and logging. Also used to │ │ │ let the cluster scaler learn a │ │ │ model for how long the job will │ │ │ take. Defaults to the job │ │ │ class's name if no real │ │ │ user-defined name is available. │ │ │ │ │ │ For a FunctionWrappingJob, the │ │ │ jobName is replaced by the │ │ │ wrapped function's name. │ │ │ │ │ │ For a CWL workflow, the jobName │ │ │ is the class name of the │ │ │ internal job that is running the │ │ │ CWL workflow, such as "CWLJob". │ ├────────────┼──────────────────────────────────┤ │unitName │ Name of this instance of this │ │ │ kind of job. If set by the user, │ │ │ it will appear with the jobName │ │ │ in logging. │ │ │ │ │ │ For a CWL workflow, the unitName │ │ │ is set to a descriptive name │ │ │ that includes the CWL file name │ │ │ and the ID in the file if set. │ ├────────────┼──────────────────────────────────┤ │displayName │ A human-readable name to │ │ │ identify this particular job │ │ │ instance. Used as an identifier │ │ │ of the job class in the stats │ │ │ report. Defaults to the job │ │ │ class's name if no real │ │ │ user-defined name is available. │ │ │ │ │ │ For a CWL workflow, the │ │ │ displayName is the absolute │ │ │ workflow URI. │ └────────────┴──────────────────────────────────┘ Optimizations Toil implements lots of optimizations designed for scalability. Here we detail some of the key optimizations. Read-only leader The leader process is currently implemented as a single thread. Most of the leader's tasks revolve around processing the state of jobs, each stored as a file within the job-store. To minimise the load on this thread, each worker does as much work as possible to manage the state of the job it is running. As a result, with a couple of minor exceptions, the leader process never needs to write or update the state of a job within the job-store. For example, when a job is complete and has no further successors the responsible worker deletes the job from the job-store, marking it complete. The leader then only has to check for the existence of the file when it receives a signal from the batch-system to know that the job is complete. This off-loading of state management is orthogonal to future parallelization of the leader. Job chaining The scheduling of successor jobs is partially managed by the worker, reducing the number of individual jobs the leader needs to process. Currently this is very simple: if the there is a single next successor job to run and its resources fit within the resources of the current job and closely match the resources of the current job then the job is run immediately on the worker without returning to the leader. Further extensions of this strategy are possible, but for many workflows which define a series of serial successors (e.g. map sequencing reads, post-process mapped reads, etc.) this pattern is very effective at reducing leader workload. Preemptable node support Critical to running at large-scale is dealing with intermittent node failures. Toil is therefore designed to always be resumable providing the job-store does not become corrupt. This robustness allows Toil to run on preemptible nodes, which are only available when others are not willing to pay more to use them. Designing workflows that divide into many short individual jobs that can use preemptable nodes allows for workflows to be efficiently scheduled and executed. Caching Running bioinformatic pipelines often require the passing of large datasets between jobs. Toil caches the results from jobs such that child jobs running on the same node can directly use the same file objects, thereby eliminating the need for an intermediary transfer to the job store. Caching also reduces the burden on the local disks, because multiple jobs can share a single file. The resulting drop in I/O allows pipelines to run faster, and, by the sharing of files, allows users to run more jobs in parallel by reducing overall disk requirements. To demonstrate the efficiency of caching, we ran an experimental internal pipeline on 3 samples from the TCGA Lung Squamous Carcinoma (LUSC) dataset. The pipeline takes the tumor and normal exome fastqs, and the tumor rna fastq and input, and predicts MHC presented neoepitopes in the patient that are potential targets for T-cell based immunotherapies. The pipeline was run individually on the samples on c3.8xlarge machines on AWS (60GB RAM,600GB SSD storage, 32 cores). The pipeline aligns the data to hg19-based references, predicts MHC haplotypes using PHLAT, calls mutations using 2 callers (MuTect and RADIA) and annotates them using SnpEff, then predicts MHC:peptide binding using the IEDB suite of tools before running an in-house rank boosting algorithm on the final calls. To optimize time taken, The pipeline is written such that mutations are called on a per-chromosome basis from the whole-exome bams and are merged into a complete vcf. Running mutect in parallel on whole exome bams requires each mutect job to download the complete Tumor and Normal Bams to their working directories -- An operation that quickly fills the disk and limits the parallelizability of jobs. The script was run in Toil, with and without caching, and Figure 2 shows that the workflow finishes faster in the cached case while using less disk on average than the uncached run. We believe that benefits of caching arising from file transfers will be much higher on magnetic disk-based storage systems as compared to the SSD systems we tested this on. [image: Graph outlining the efficiency gain from caching.] [image] Figure 2: Efficiency gain from caching. The lower half of each plot describes the disk used by the pipeline recorded every 10 minutes over the duration of the pipeline, and the upper half shows the corresponding stage of the pipeline that is being processed. Since jobs requesting the same file shared the same inode, the effective load on the disk is considerably lower than in the uncached case where every job downloads a personal copy of every file it needs. We see that in all cases, the uncached run uses almost 300-400GB more that the cached run in the resource heavy mutation calling step. We also see a benefit in terms of wall time for each stage since we eliminate the time taken for file transfers..UNINDENT Toil support for Common Workflow Language The CWL document and input document are loaded using the 'cwltool.load_tool' module. This performs normalization and URI expansion (for example, relative file references are turned into absolute file URIs), validates the document against the CWL schema, initializes Python objects corresponding to major document elements (command line tools, workflows, workflow steps), and performs static type checking that sources and sinks have compatible types. Input files referenced by the CWL document and input document are imported into the Toil file store. CWL documents may use any URI scheme supported by Toil file store, including local files and object storage. The 'location' field of File references are updated to reflect the import token returned by the Toil file store. For directory inputs, the directory listing is stored in Directory object. Each individual files is imported into Toil file store. An initial workflow Job is created from the toplevel CWL document. Then, control passes to the Toil engine which schedules the initial workflow job to run. When the toplevel workflow job runs, it traverses the CWL workflow and creates a toil job for each step. The dependency graph is expressed by making downstream jobs children of upstream jobs, and initializing the child jobs with an input object containing the promises of output from upstream jobs. Because Toil jobs have a single output, but CWL permits steps to have multiple output parameters that may feed into multiple other steps, the input to a CWLJob is expressed with an "indirect dictionary". This is a dictionary of input parameters, where each entry value is a tuple of a promise and a promise key. When the job runs, the indirect dictionary is turned into a concrete input object by resolving each promise into its actual value (which is always a dict), and then looking up the promise key to get the actual value for the the input parameter. If a workflow step specifies a scatter, then a scatter job is created and connected into the workflow graph as described above. When the scatter step runs, it creates child jobs for each parameterizations of the scatter. A gather job is added as a follow-on to gather the outputs into arrays. When running a command line tool, it first creates output and temporary directories under the Toil local temp dir. It runs the command line tool using the single_job_executor from CWLTool, providing a Toil-specific constructor for filesystem access, and overriding the default PathMapper to use ToilPathMapper. The ToilPathMapper keeps track of a file's symbolic identifier (the Toil FileID), its local path on the host (the value returned by readGlobalFile) and the the location of the file inside the Docker container. After executing single_job_executor from CWLTool, it gets back the output object and status. If the underlying job failed, raise an exception. Files from the output object are added to the file store using writeGlobalFile and the 'location' field of File references are updated to reflect the token returned by the Toil file store. When the workflow completes, it returns an indirect dictionary linking to the outputs of the job steps that contribute to the final output. This is the value returned by toil.start() or toil.restart(). This is resolved to get the final output object. The files in this object are exported from the file store to 'outdir' on the host file system, and the 'location' field of File references are updated to reflect the final exported location of the output files.
MINIMUM AWS IAM PERMISSIONS
Toil requires at least the following permissions in an IAM role to operate on a cluster. These are added by default when launching a cluster. However, ensure that they are present if creating a custom IAM role when launching a cluster with the --awsEc2ProfileArn parameter. { "Version": "2012-10-17", "Statement": [ { "Effect": "Allow", "Action": [ "ec2:*", "s3:*", "sdb:*", "iam:PassRole" ], "Resource": "*" } ] }
AUTO-DEPLOYMENT
If you want to run your workflow in a distributed environment, on multiple worker machines, either in the cloud or on a bare-metal cluster, your script needs to be made available to those other machines. If your script imports other modules, those modules also need to be made available on the workers. Toil can automatically do that for you, with a little help on your part. We call this feature auto-deployment of a workflow. Let's first examine various scenarios of auto-deploying a workflow, which, as we'll see shortly cannot be auto-deployed. Lastly, we'll deal with the issue of declaring Toil as a dependency of a workflow that is packaged as a setuptools distribution. Toil can be easily deployed to a remote host. First, assuming you've followed our prepareAWS section to install Toil and use it to create a remote leader node on (in this example) AWS, you can now log into this into using sshCluster and once on the remote host, create and activate a virtualenv (noting to make sure to use the --system-site-packages option!): $ virtualenv --system-site-packages venv $ . venv/bin/activate Note the --system-site-packages option, which ensures that globally-installed packages are accessible inside the virtualenv. Do not (re)install Toil after this! The --system-site-packages option has already transferred Toil and the dependencies from your local installation of Toil for you. From here, you can install a project and its dependencies: $ tree . ├── util │ ├── __init__.py │ └── sort │ ├── __init__.py │ └── quick.py └── workflow ├── __init__.py └── main.py 3 directories, 5 files $ pip install matplotlib $ cp -R workflow util venv/lib/python2.7/site-packages Ideally, your project would have a setup.py file (see setuptools) which streamlines the installation process: $ tree . ├── util │ ├── __init__.py │ └── sort │ ├── __init__.py │ └── quick.py ├── workflow │ ├── __init__.py │ └── main.py └── setup.py 3 directories, 6 files $ pip install . Or, if your project has been published to PyPI: $ pip install my-project In each case, we have created a virtualenv with the --system-site-packages flag in the venv subdirectory then installed the matplotlib distribution from PyPI along with the two packages that our project consists of. (Again, both Python and Toil are assumed to be present on the leader and all worker nodes.) We can now run our workflow: $ python main.py --batchSystem=mesos … IMPORTANT: If workflow's external dependencies contain native code (i.e. are not pure Python) then they must be manually installed on each worker. WARNING: Neither python setup.py develop nor pip install -e . can be used in this process as, instead of copying the source files, they create .egg-link files that Toil can't auto-deploy. Similarly, python setup.py install doesn't work either as it installs the project as a Python .egg which is also not currently supported by Toil (though it could be in the future). Also note that using the --single-version-externally-managed flag with setup.py will prevent the installation of your package as an .egg. It will also disable the automatic installation of your project's dependencies. Auto Deployment with Sibling Modules This scenario applies if the user script imports modules that are its siblings: $ cd my_project $ ls userScript.py utilities.py $ ./userScript.py --batchSystem=mesos … Here userScript.py imports additional functionality from utilities.py. Toil detects that userScript.py has sibling modules and copies them to the workers, alongside the user script. Note that sibling modules will be auto-deployed regardless of whether they are actually imported by the user script–all .py files residing in the same directory as the user script will automatically be auto-deployed. Sibling modules are a suitable method of organizing the source code of reasonably complicated workflows. Auto-Deploying a Package Hierarchy Recall that in Python, a package is a directory containing one or more .py files—one of which must be called __init__.py—and optionally other packages. For more involved workflows that contain a significant amount of code, this is the recommended way of organizing the source code. Because we use a package hierarchy, we can't really refer to the user script as such, we call it the user module instead. It is merely one of the modules in the package hierarchy. We need to inform Toil that we want to use a package hierarchy by invoking Python's -m option. That enables Toil to identify the entire set of modules belonging to the workflow and copy all of them to each worker. Note that while using the -m option is optional in the scenarios above, it is mandatory in this one. The following shell session illustrates this: $ cd my_project $ tree . ├── utils │ ├── __init__.py │ └── sort │ ├── __init__.py │ └── quick.py └── workflow ├── __init__.py └── main.py 3 directories, 5 files $ python -m workflow.main --batchSystem=mesos … Here the user module main.py does not reside in the current directory, but is part of a package called util, in a subdirectory of the current directory. Additional functionality is in a separate module called util.sort.quick which corresponds to util/sort/quick.py. Because we invoke the user module via python -m workflow.main, Toil can determine the root directory of the hierarchy–my_project in this case–and copy all Python modules underneath it to each worker. The -m option is documented here When -m is passed, Python adds the current working directory to sys.path, the list of root directories to be considered when resolving a module name like workflow.main. Without that added convenience we'd have to run the workflow as PYTHONPATH="$PWD" python -m workflow.main. This also means that Toil can detect the root directory of the user module's package hierarchy even if it isn't the current working directory. In other words we could do this: $ cd my_project $ export PYTHONPATH="$PWD" $ cd /some/other/dir $ python -m workflow.main --batchSystem=mesos … Also note that the root directory itself must not be package, i.e. must not contain an __init__.py. Relying on Shared Filesystems Bare-metal clusters typically mount a shared file system like NFS on each node. If every node has that file system mounted at the same path, you can place your project on that shared filesystem and run your user script from there. Additionally, you can clone the Toil source tree into a directory on that shared file system and you won't even need to install Toil on every worker. Be sure to add both your project directory and the Toil clone to PYTHONPATH. Toil replicates PYTHONPATH from the leader to every worker. Using a shared filesystem Toil currently only supports a tempdir set to a local, non-shared directory. Toil Appliance The term Toil Appliance refers to the Mesos Docker image that Toil uses to simulate the machines in the virtual mesos cluster. It's easily deployed, only needs Docker, and allows for workflows to be run in single-machine mode and for clusters of VMs to be provisioned. To specify a different image, see the Toil envars section. For more information on the Toil Appliance, see the runningAWS section.
ENVIRONMENT VARIABLES
There are several environment variables that affect the way Toil runs. ┌────────────────────────────────┬─────────────────────────────────────┐ │TOIL_CHECK_ENV │ A flag that determines whether │ │ │ Toil will try to refer back to a │ │ │ Python virtual environment in │ │ │ which it is installed when │ │ │ composing commands that may be │ │ │ run on other hosts. If set to │ │ │ True, if Toil is installed in │ │ │ the current virtual environment, │ │ │ it will use absolute paths to │ │ │ its own executables (and the │ │ │ virtual environment must thus be │ │ │ available on at the same path on │ │ │ all nodes). Otherwise, Toil │ │ │ internal commands such as │ │ │ _toil_worker will be resolved │ │ │ according to the PATH on the │ │ │ node where they are executed. │ │ │ This setting can be useful in a │ │ │ shared HPC environment, where │ │ │ users may have their own Toil │ │ │ installations in virtual │ │ │ environments. │ ├────────────────────────────────┼─────────────────────────────────────┤ │TOIL_WORKDIR │ An absolute path to a directory │ │ │ where Toil will write its │ │ │ temporary files. This directory │ │ │ must exist on each worker node │ │ │ and may be set to a different │ │ │ value on each worker. The │ │ │ --workDir command line option │ │ │ overrides this. When using the │ │ │ Toil docker container, such as │ │ │ on Kubernetes, this defaults to │ │ │ /var/lib/toil. When using Toil │ │ │ autoscaling with Mesos, this is │ │ │ somewhere inside the Mesos │ │ │ sandbox. In all other cases, the │ │ │ system's standard temporary │ │ │ directory is used. │ ├────────────────────────────────┼─────────────────────────────────────┤ │TOIL_WORKDIR_OVERRIDE │ An absolute path to a directory │ │ │ where Toil will write its │ │ │ temporary files. This overrides │ │ │ TOIL_WORKDIR and the --workDir │ │ │ command line option. │ ├────────────────────────────────┼─────────────────────────────────────┤ │TOIL_KUBERNETES_HOST_PATH │ A path on Kubernetes hosts that │ │ │ will be mounted as the Toil work │ │ │ directory in the workers, to │ │ │ allow for shared caching. │ └────────────────────────────────┴─────────────────────────────────────┘ │TOIL_KUBERNETES_OWNER │ A name prefix for easy │ │ │ identification of Kubernetes │ │ │ jobs. If not set, Toil will use │ │ │ the current user name. │ ├────────────────────────────────┼─────────────────────────────────────┤ │TOIL_KUBERNETES_SERVICE_ACCOUNT │ A service account name to apply │ │ │ when creating Kubernetes pods. │ ├────────────────────────────────┼─────────────────────────────────────┤ │KUBE_WATCH_ENABLED │ A boolean variable that allows │ │ │ for users to utilize kubernetes │ │ │ watch stream feature instead of │ │ │ polling for running jobs. │ │ │ Default value is set to False. │ ├────────────────────────────────┼─────────────────────────────────────┤ │TOIL_TES_ENDPOINT │ URL to the TES server to run │ │ │ against when using the tes batch │ │ │ system. │ ├────────────────────────────────┼─────────────────────────────────────┤ │TOIL_TES_USER │ Username to use with HTTP Basic │ │ │ Authentication to log into the │ │ │ TES server. │ ├────────────────────────────────┼─────────────────────────────────────┤ │TOIL_TES_PASSWORD │ Password to use with HTTP Basic │ │ │ Authentication to log into the │ │ │ TES server. │ ├────────────────────────────────┼─────────────────────────────────────┤ │TOIL_TES_BEARER_TOKEN │ Token to use to authenticate to │ │ │ the TES server. │ ├────────────────────────────────┼─────────────────────────────────────┤ │TOIL_APPLIANCE_SELF │ The fully qualified reference │ │ │ for the Toil Appliance you wish │ │ │ to use, in the form │ │ │ REPO/IMAGE:TAG. │ │ │ quay.io/ucsc_cgl/toil:3.6.0 and │ │ │ cket/toil:3.5.0 are both │ │ │ examples of valid options. Note │ │ │ that since Docker defaults to │ │ │ Dockerhub repos, only quay.io │ │ │ repos need to specify their │ │ │ registry. │ ├────────────────────────────────┼─────────────────────────────────────┤ │TOIL_DOCKER_REGISTRY │ The URL of the registry of the │ │ │ Toil Appliance image you wish to │ │ │ use. Docker will use Dockerhub │ │ │ by default, but the quay.io │ │ │ registry is also very popular │ │ │ and easily specifiable by │ │ │ setting this option to quay.io. │ ├────────────────────────────────┼─────────────────────────────────────┤ │TOIL_DOCKER_NAME │ The name of the Toil Appliance │ │ │ image you wish to use. Generally │ │ │ this is simply toil but this │ │ │ option is provided to override │ │ │ this, since the image can be │ │ │ built with arbitrary names. │ ├────────────────────────────────┼─────────────────────────────────────┤ │TOIL_AWS_SECRET_NAME │ For the Kubernetes batch system, │ │ │ the name of a Kubernetes secret │ │ │ which contains a credentials │ │ │ file granting access to AWS │ │ │ resources. Will be mounted as │ │ │ ~/.aws inside Kubernetes-managed │ │ │ Toil containers. Enables the │ │ │ AWSJobStore to be used with the │ │ │ Kubernetes batch system, if the │ │ │ credentials allow access to S3 │ │ │ and SimpleDB. │ ├────────────────────────────────┼─────────────────────────────────────┤ │TOIL_AWS_ZONE │ The EC2 zone to provision nodes │ │ │ in if using Toil's provisioner. │ ├────────────────────────────────┼─────────────────────────────────────┤ │TOIL_AWS_AMI │ ID of the AMI to use in node │ │ │ provisioning. If in doubt, don't │ │ │ set this variable. │ ├────────────────────────────────┼─────────────────────────────────────┤ │TOIL_AWS_NODE_DEBUG │ Determines whether to preserve │ │ │ nodes that have failed health │ │ │ checks. If set to True, nodes │ │ │ that fail EC2 health checks │ │ │ won't immediately be terminated │ │ │ so they can be examined and the │ │ │ cause of failure determined. If │ │ │ any EC2 nodes are left behind in │ │ │ this manner, the security group │ │ │ will also be left behind by │ │ │ necessity as it cannot be │ │ │ deleted until all associated │ │ │ nodes have been terminated. │ └────────────────────────────────┴─────────────────────────────────────┘ │TOIL_GOOGLE_PROJECTID │ The Google project ID to use │ │ │ when generating Google job store │ │ │ names for tests or CWL │ │ │ workflows. │ ├────────────────────────────────┼─────────────────────────────────────┤ │TOIL_SLURM_ARGS │ Arguments for sbatch for the │ │ │ slurm batch system. Do not pass │ │ │ CPU or memory specifications │ │ │ here. Instead, define resource │ │ │ requirements for the job. There │ │ │ is no default value for this │ │ │ variable. │ ├────────────────────────────────┼─────────────────────────────────────┤ │TOIL_GRIDENGINE_ARGS │ Arguments for qsub for the │ │ │ gridengine batch system. Do not │ │ │ pass CPU or memory │ │ │ specifications here. Instead, │ │ │ define resource requirements for │ │ │ the job. There is no default │ │ │ value for this variable. │ ├────────────────────────────────┼─────────────────────────────────────┤ │TOIL_GRIDENGINE_PE │ Parallel environment arguments │ │ │ for qsub and for the gridengine │ │ │ batch system. There is no │ │ │ default value for this variable. │ ├────────────────────────────────┼─────────────────────────────────────┤ │TOIL_TORQUE_ARGS │ Arguments for qsub for the │ │ │ Torque batch system. Do not │ │ │ pass CPU or memory │ │ │ specifications here. Instead, │ │ │ define extra parameters for the │ │ │ job such as queue. Example: -q │ │ │ medium Use TOIL_TORQUE_REQS to │ │ │ pass extra values for the -l │ │ │ resource requirements parameter. │ │ │ There is no default value for │ │ │ this variable. │ ├────────────────────────────────┼─────────────────────────────────────┤ │TOIL_TORQUE_REQS │ Arguments for the resource │ │ │ requirements for Torque batch │ │ │ system. Do not pass CPU or │ │ │ memory specifications here. │ │ │ Instead, define extra resource │ │ │ requirements as a string that │ │ │ goes after the -l argument to │ │ │ qsub. Example: │ │ │ walltime=2:00:00,file=50gb There │ │ │ is no default value for this │ │ │ variable. │ ├────────────────────────────────┼─────────────────────────────────────┤ │TOIL_LSF_ARGS │ Additional arguments for the │ │ │ LSF's bsub command. Instead, │ │ │ define extra parameters for the │ │ │ job such as queue. Example: -q │ │ │ medium. There is no default │ │ │ value for this variable. │ ├────────────────────────────────┼─────────────────────────────────────┤ │TOIL_HTCONDOR_PARAMS │ Additional parameters to include │ │ │ in the HTCondor submit file │ │ │ passed to condor_submit. Do not │ │ │ pass CPU or memory │ │ │ specifications here. Instead │ │ │ define extra parameters which │ │ │ may be required by HTCondor. │ │ │ This variable is parsed as a │ │ │ semicolon-separated string of │ │ │ parameter = value pairs. │ │ │ Example: requirements = │ │ │ TARGET.has_sse4_2 == true; │ │ │ accounting_group = test. There │ │ │ is no default value for this │ │ │ variable. │ ├────────────────────────────────┼─────────────────────────────────────┤ │TOIL_CUSTOM_DOCKER_INIT_COMMAND │ Any custom bash command to run │ │ │ in the Toil docker container │ │ │ prior to running the Toil │ │ │ services. Can be used for any │ │ │ custom initialization in the │ │ │ worker and/or primary nodes such │ │ │ as private docker docker │ │ │ authentication. Example for AWS │ │ │ ECR: pip install awscli && eval │ │ │ $(aws ecr get-login │ │ │ --no-include-email --region │ │ │ us-east-1). │ └────────────────────────────────┴─────────────────────────────────────┘ │TOIL_CUSTOM_INIT_COMMAND │ Any custom bash command to run │ │ │ prior to starting the Toil │ │ │ appliance. Can be used for any │ │ │ custom initialization in the │ │ │ worker and/or primary nodes such │ │ │ as private docker authentication │ │ │ for the Toil appliance itself │ │ │ (i.e. from TOIL_APPLIANCE_SELF). │ ├────────────────────────────────┼─────────────────────────────────────┤ │TOIL_S3_HOST │ the IP address or hostname to │ │ │ use for connecting to S3. │ │ │ Example: TOIL_S3_HOST=127.0.0.1 │ ├────────────────────────────────┼─────────────────────────────────────┤ │TOIL_S3_PORT │ a port number to use for │ │ │ connecting to S3. Example: │ │ │ TOIL_S3_PORT=9001 │ ├────────────────────────────────┼─────────────────────────────────────┤ │TOIL_S3_USE_SSL │ enable or disable the usage of │ │ │ SSL for connecting to S3 (True │ │ │ by default). Example: │ │ │ TOIL_S3_USE_SSL=False │ ├────────────────────────────────┼─────────────────────────────────────┤ │TOIL_WES_BROKER_URL │ An optional broker URL to use to │ │ │ communicate between the WES │ │ │ server and Celery task queue. If │ │ │ unset, │ │ │ amqp://guest:guest@localhost:5672// │ │ │ is used. │ ├────────────────────────────────┼─────────────────────────────────────┤ │TOIL_OWNER_TAG │ This will tag cloud resources with │ │ │ a tag reading: "Owner: │ │ │ $TOIL_OWNER_TAG". This is used │ │ │ internally at UCSC to stop a bot we │ │ │ have that terminates untagged │ │ │ resources. │ ├────────────────────────────────┼─────────────────────────────────────┤ │SINGULARITY_DOCKER_HUB_MIRROR │ An http or https URL for the │ │ │ Singularity wrapper in the Toil │ │ │ Docker container to use as a mirror │ │ │ for Docker Hub. │ ├────────────────────────────────┼─────────────────────────────────────┤ │OMP_NUM_THREADS │ The number of cores set for OpenMP │ │ │ applications in the workers. If not │ │ │ set, Toil will use the number of │ │ │ job threads. │ └────────────────────────────────┴─────────────────────────────────────┘ · genindex · search
AUTHOR
UCSC Computational Genomics Lab
COPYRIGHT
2022 – 2022 UCSC Computational Genomics Lab