Provided by: task_2.2.0-3_amd64 
NAME
task-sync - A tutorial for the task(1) data synchronization capabilities.
DESCRIPTION
Taskwarrior has built-in support for synchronization, which can be used to keep two task
databases up to date, regardless of which one is used. This capability can also be used
to keep a backup copy of your task database on another machine.
Taskwarrior can use various protocols for transferring the data.
HOW IT WORKS
If you were to manually attempt to keep two separate task databases up to date, you would
need to inspect both databases, and detect changes that occurred in each one. Those
changes would need to be migrated to the other database, while being careful not to miss a
change, and not to confuse an 'add' in one with a 'delete' in the other.
The synchronization feature does just this. It can transfer task databases, compare
tasks, and apply changes where necessary.
NEW COMMANDS
Taskwarrior has 'pull', 'push' and 'merge' commands which perform the steps necessary to
move files around and combine them. In the common use case, you would only need to use
the 'merge' command. These commands take an argument that is a URI, which indicates where
the remote database resides.
To be clear, the local database always refers to your ~/.task directory (unless
overridden), and the remote database is always specified by URI.
MERGE
The merge command will fetch task data via URI and combine it with the local task
database. The syntax is:
task merge [<URI>]
The URI is optional if the merge.default.uri configuration variable is set. The URI may
point to a different directory, or it may be a different computer. Here is an example of
the merge command:
$ task merge ~/work/
This URI (~/work/) is a path name, which means the remote database is on the same
computer. Taskwarrior will fetch the data from the URI, and merge it with your local data
in ~/.task.
When complete, you will be asked whether you would like to push the combined data back to
the remote location specified by the URI. This is useful if you are keeping two task
databases synchronized, but it can be turned off. See CONFIGURATION.
Note that a merge operation is not atomically reversible. You could however run the 'task
undo' command repeatedly to undo the effects.
PUSH
The push command will copy the local task database to the specified URI. The syntax is:
task push [<URI>]
The URI is optional if the push.default.uri configuration variable is set. This command
is useful for making backup copies of your task database.
Note that the task files at the location specified by the URI are simply overwritten, so
don't expect any merging to occur. Misused, push can be dangerous.
PULL
The pull command will copy a task database from a URI to the local task database (~/.task
by default). The syntax is:
task pull [<URI>]
The URI is optional if the pull.default.uri configuration variable is set. This command
is useful for restoring a backup copy of your task database.
Note that your local task database files will be simply overwritten by the files obtained
from the location specified by the URI, so don't expect any merging to occur. Misused,
pull can be dangerous.
URI TYPES
The most basic URI is a path name on the local machine. An example would be:
/home/bob/.task/
All the other URIs allow access to remote machines. The first uses SSH and scp (either
form can be used):
ssh://[user@]host[:port]/absolute/path/to/.task/
[user@]host:/absolute/path/to/.task/
In both cases paths are considered to be absolute. You can specify paths relative to the
users home directory as follows:
ssh://[user@]host[:port]/.task/
[user@]host:.task/
or even shorter
[user@]host:.task/
Remark: Since taskwarrior simply calls the scp binary you can specify very much anything
that scp would accept, e.g. host configurations from ~/.ssh/config or ~username expansion:
ssh://configured-host/~[username]/.task/
configured-host:~[username]/.task/
Rsync is another supported protocol that minimizes network traffic, by a clever algorithm
that doesn't copy files that have not changed:
rsync://[user@]host.xz[:port]/path/to/.task/
Curl supports several protocols that can transfer data using HTTP, HTTPS and FTP:
http://host[:port]/path/to/.task/
https://host[:port]/path/to/.task/
ftp://[user@]host[:port]/path/to/.task/
You can use single quotes to encapsulate user names that contain delimiting characters
like '@', '/' or ':', e.g.:
ssh://'user@name'@host/
Remember to escape the quotes on your shell:
$ task push ftp://´user@name´:host/
CONFLICTS
When modifications on the local and remote machine conflict, for example if both machines
change the project name of the same task to different values, then Taskwarrior
automatically selects the most recent change. Thus, there are no conflicts.
EXAMPLE - Backup on another machine
One very good use of 'push' is to make backup copies of your task database in another
location. Suppose your task database is kept in the usual place, in the ~/.task
directory, and you wanted to make a backup copy in ~/backup. You would use this command:
$ task push ~/backup/
This would copy the files in ~/.task to ~/backup, overwriting the files that were already
in ~/backup. To backup your files to another machine, you could use:
$ task push user@host:backup
This could be improved by setting the push.default.uri configuration variable and then
relying on the default, like this:
$ task config push.default.uri user@host:backup
and then you need only run the push command:
$ task push
and the default push URI will be used. If you wanted to restore a backup, you simply use
the pull command instead:
$ task pull user@host:backup
This can be simplified by setting the pull.default.uri configuration variable and then
relying on the default, like this:
$ task config pull.default.uri user@host:backup
Note that pull and push will blindly overwrite the task files without any merging. Be
careful.
EXAMPLE - Keeping two task databases synchronized
The most common synchronization will be to keep two task databases synchronized on
different machines. Here is a full example, including setup that illustrates this.
Suppose there are two machines, named 'local' and 'remote', for simplicity. Taskwarrior
is installed on both machines. The different machines are indicated here by the prompt.
Suppose Alice enters two tasks on her local machine:
local> task add Deliver the new budget proposal due:tuesday
local> task add Set up a meeting with Bob
Then later adds a task on the remote machine:
remote> task add Present the budget proposal at the big meeting due:thursday
Now on the local machine, Alice merges the two task databases:
local> task merge alice@remote:.task
Would you like to push the changes to 'alice@remote:.task'? Y
Taskwarrior has combined the two task databases on local, then pushed the changes back to
remote. Now suppose Alice changes the due date for task 1 on remote:
remote> task 1 due:wednesday
Now on the local machine, Alice sets up a default URI and autopush:
local> task config merge.default.uri alice@remote:.task
local> task config merge.autopush yes
Now Alice can simply run merge to make sure that the new due date is copied to the local
machine:
local> task merge
This time the URI is determined automatically, and after the merge the files are pushed
back to the remote machine. In a similar way, the remote machine can also be configured
to merge from the local machine and push back to it. Then it is just a matter of Alice
remembering to merge now and then, from either machine, to have her data in two (or even
more) places.
CONFIGURATION
By setting these configuration variables, it is possible to simplify the synchronization
commands, by relying on the defaults or alias names.
merge.autopush=yes|no|ask
This controls whether the automatic push after a merge is performed, not performed,
or whether the user is asked every time. The default value is 'ask'.
merge.default.uri=<uri>
Sets a default URI so that just the 'task merge' command be run without the need to
retype the URI every time. You can also use this configuration scheme to set alias
names, e.g. set merge.desktop.uri and run 'task merge desktop'.
push.default.uri=<uri>
Sets a default URI so that just the 'task push' command be run without the need to
retype the URI every time. You can also use this configuration scheme to set alias
names, e.g. set push.desktop.uri and run 'task push desktop'.
pull.default.uri=<uri>
Sets a default URI so that just the 'task pull' command be run without the need to
retype the URI every time. You can also use this configuration scheme to set alias
names, e.g. set pull.desktop.uri and run 'task pull desktop'.
Note that, when using SSH/scp, hostnames will be expanded due to the ssh configuration
file ~/.ssh/config.
EXTERNAL DEPENDENCIES
Depending on the URI protocols used, the utilities 'scp', 'rsync' and 'curl' must be
installed and accessible via the $PATH environment variable.
If you have deleted your ~/.task/undo.data file to save space, you will be unable to
merge. The change transactions stored in the undo.data file are used for synchronization.
CREDITS & COPYRIGHTS
Copyright (C) 2006 - 2013 P. Beckingham, F. Hernandez.
The sync capabilities were written by J. Schlatow. Parts copyright (C) 2010 - 2013 J.
Schlatow.
Taskwarrior is distributed under the MIT license. See
http://www.opensource.org/licenses/mit-license.php for more information.
SEE ALSO
task(1), taskrc(5), task-faq(5), task-color(5), task-tutorial(5), ssh_config(5)
For more information regarding task, the following may be referenced:
The official site at
<http://taskwarrior.org>
The official code repository at
<git://tasktools.org/task.git/>
You can contact the project by writing an email to
<support@taskwarrior.org>
REPORTING BUGS
Bugs in task may be reported to the issue-tracker at
<http://taskwarrior.org>