Provided by: git-annex_8.20210223-2ubuntu2_amd64 
NAME
git-annex-export - export a tree of files to a special remote
SYNOPSIS
git annex export treeish --to remote
DESCRIPTION
Use this command to export a tree of files from a git-annex repository.
Normally files are stored on a git-annex special remote named by their keys. That is great
for reliable data storage, but your filenames are obscured. Exporting replicates the tree
to the special remote as-is.
Mixing key/value storage and exports in the same remote would be a mess and so is not
allowed. You have to configure a special remote with exporttree=yes when initially setting
it up with git-annex-initremote(1).
The treeish to export can be the name of a git branch, or a tag, or any other treeish
accepted by git, including eg master:subdir to only export a subdirectory from a branch.
When the remote has a preferred content expression set by git-annex-wanted(1), the treeish
is filtered through it, excluding annexed files it does not want from being exported to
it. (Note that things in the expression like "include=" match relative to the top of the
treeish being exported.)
Any files in the treeish that are stored on git will also be exported to the special
remote.
Repeated exports are done efficiently, by diffing the old and new tree, and transferring
only the changed files, and renaming files as necessary.
Exports can be interrupted and resumed. However, partially uploaded files will be
re-started from the beginning in most cases.
Once content has been exported to a remote, commands like git annex get can download
content from there the same as from other remotes. However, since an export is not a
key/value store, git-annex has to do more verification of content downloaded from an
export. Some types of keys, that are not based on checksums, cannot be downloaded from an
export. And, git-annex will never trust an export to retain the content of a key.
However, some special remotes, notably S3, support keeping track of old versions of files
stored in them. If a special remote is set up to do that, it can be used as a key/value
store and the limitations in the above paragraph do not apply. Note that dropping content
from such a remote is not supported. See individual special remotes' documentation for
details of how to enable such versioning.
The git annex sync --content command (and the git-annex assistant) can also be used to
export a branch to a special remote, updating the special remote whenever the branch is
changed. To do this, you need to configure "remote.<name>.annex-tracking-branch" to tell
it what branch to track. For example:
git config remote.myremote.annex-tracking-branch master
git annex sync --content
You can combine using git annex export to send changes to a special remote with git annex
import to fetch changes from a special remote. When a file on a special remote has been
modified by software other than git-annex, exporting to it will not overwrite the modified
file, and the export will not succeed. You can resolve this conflict by using git annex
import.
(Some types of special remotes such as S3 with versioning may instead let an export
overwrite the modified file; then git annex import will create a sequence of commits that
includes the modified file, so the overwritten modification is not lost.)
OPTIONS
--to=remote
Specify the special remote to export to.
--tracking
This is a deprecated way to set "remote.<name>.annex-tracking-branch". Instead of
using this option, you should just set the git configuration yourself.
--fast This sets up an export of a tree, but avoids any expensive file uploads to the
remote. You can later run git annex sync --content to upload the files to the
export.
--jobs=N -JN
Exports multiple files in parallel. This may be faster. For example: -J4
Setting this to "cpus" will run one job per CPU core.
--json Enable JSON output. This is intended to be parsed by programs that use git-annex.
Each line of output is a JSON object.
--json-progress
Include progress objects in JSON output.
--json-error-messages
Messages that would normally be output to standard error are included in the json
instead.
EXAMPLE
git annex initremote myremote type=directory directory=/mnt/myremote exporttree=yes
encryption=none
git annex export master --to myremote
After that, /mnt/myremote will contain the same tree of files as the master branch does.
git mv myfile subdir/myfile
git commit -m renamed
git annex export master --to myremote
That updates /mnt/myremote to reflect the renamed file.
git annex export master:subdir --to myremote
That updates /mnt/myremote, to contain only the files in the "subdir" directory of the
master branch.
EXPORT CONFLICTS
If two different git-annex repositories are both exporting different trees to the same
special remote, it's possible for an export conflict to occur. This leaves the special
remote with some files from one tree, and some files from the other. Files in the special
remote may have entirely the wrong content as well.
It's not possible for git-annex to detect when making an export will result in an export
conflict. The best way to avoid export conflicts is to either only ever export to a
special remote from a single repository, or to have a rule about the tree that you export
to the special remote. For example, if you always export origin/master after pushing to
origin, then an export conflict can't happen.
An export conflict can only be detected after the two git repositories that produced it
get back in sync. Then the next time you run git annex export, it will detect the export
conflict, and resolve it.
SEE ALSO
git-annex(1)
git-annex-initremote(1)
git-annex-import(1)
git-annex-sync(1)
git-annex-preferred-content(1)
HISTORY
The export command was introduced in git-annex version 6.20170925.
AUTHOR
Joey Hess <id@joeyh.name>
git-annex-export(1)