git-annex/doc/git-annex.mdwn

369 lines
11 KiB
Markdown

# NAME
git-annex - manage files with git, without checking their contents in
# SYNOPSIS
git annex subcommand [params ...]
# DESCRIPTION
git-annex allows managing files with git, without checking the file
contents into git. While that may seem paradoxical, it is useful when
dealing with files larger than git can currently easily handle, whether due
to limitations in memory, checksumming time, or disk space.
Even without file content tracking, being able to manage files with git,
move files around and delete files with versioned directory trees, and use
branches and distributed clones, are all very handy reasons to use git. And
annexed files can co-exist in the same git repository with regularly
versioned files, which is convenient for maintaining documents, Makefiles,
etc that are associated with annexed files but that benefit from full
revision control.
When a file is annexed, its content is moved into a key-value store, and
a symlink is made that points to the content. These symlinks are checked into
git and versioned like regular files. You can move them around, delete
them, and so on. Pushing to another git repository will make git-annex
there aware of the annexed file, and it can be used to retrieve its
content from the key-value store.
# EXAMPLES
# git annex get video/hackity_hack_and_kaxxt.mov
get video/_why_hackity_hack_and_kaxxt.mov (not available)
I was unable to access these remotes: server
Try making some of these repositories available:
5863d8c0-d9a9-11df-adb2-af51e6559a49 -- my home file server
58d84e8a-d9ae-11df-a1aa-ab9aa8c00826 -- portable USB drive
ca20064c-dbb5-11df-b2fe-002170d25c55 -- backup SATA drive
failed
# sudo mount /media/usb
# git remote add usbdrive /media/usb
# git annex get video/hackity_hack_and_kaxxt.mov
get video/hackity_hack_and_kaxxt.mov (copying from usbdrive...) ok
# git commit -a -m "got a video I want to rewatch on the plane"
# git annex add iso
add iso/Debian_5.0.iso ok
# git commit -a -m "saving Debian CD for later"
# git annex drop iso/Debian_4.0.iso
drop iso/Debian_4.0.iso ok
# git commit -a -m "freed up space"
# git annex move iso --to=usbdrive
move iso/Debian_5.0.iso (moving to usbdrive...) ok
# SUBCOMMANDS
Like many git commands, git-annex can be passed a path that
is either a file or a directory. In the latter case it acts on all relevant
files in the directory.
Many git-annex subcommands will stage changes for later `git commit` by you.
* add [path ...]
Adds files in the path to the annex. Files that are already checked into
git, or that git has been configured to ignore will be silently skipped.
* get [path ...]
Makes the content of annexed files available in this repository. Depending
on the backend used, this will involve copying them from another repository,
or downloading them, or transferring them from some kind of key-value store.
* drop [path ...]
Drops the content of annexed files from this repository.
git-annex may refuse to drop content if the backend does not think
it is safe to do so, typically because of the setting of annex.numcopies.
* unlock [path ...]
Normally, the content of annexed files is protected from being changed.
Unlocking a annexed file allows it to be modified. This replaces the
symlink for each specified file with a copy of the file's content.
You can then modify it and `git annex add` (or `git commit`) to inject
it back into the annex.
* edit [path ...]
This is an alias for the unlock subcommand. May be easier to remember,
if you think of this as allowing you to edit an annexed file.
* move [path ...]
When used with the --to option, moves the content of annexed files from
the current repository to the specified one.
When used with the --from option, moves the content of annexed files
from the specified repository to the current one.
* copy [path ...]
When used with the --to option, copies the content of annexed files from
the current repository to the specified one.
When used with the --from option, copies the content of annexed files
from the specified repository to the current one.
* init description
Initializes git-annex with a description of the git repository,
and sets up `.gitattributes` and the pre-commit hook.
* lock [path ...]
Use this to undo an unlock command if you don't want to modify
the files, or have made modifications you want to discard.
* fsck [path ...]
With no parameters, this subcommand checks the whole annex for consistency,
and warns about any problems found.
With parameters, only the specified files are checked.
* unused
Checks the annex for data that is not used by any files currently
in the annex, and prints a numbered list of the data.
* dropunused [number ...]
Drops the data corresponding to the numbers, as listed by the last
`git annex unused`
* find [path ...]
Outputs a list of annexed files whose content is currently present.
With no parameters, defaults to finding all files in the current directory
and its subdirectories.
* unannex [path ...]
Use this to undo an accidental add command. This is not the command you
should use if you intentionally annexed a file and don't want its contents
any more. In that case you should use `git annex drop` instead, and you
can also `git rm` the file.
* uninit
Use this to stop using git annex. It will unannex every file in the
repository, and remove all of git-annex's other data, leaving you with a
git repository plus the previously annexed files.
* fix [path ...]
Fixes up symlinks that have become broken to again point to annexed content.
This is useful to run if you have been moving the symlinks around.
* pre-commit [path ...]
Fixes up symlinks that are staged as part of a commit, to ensure they
point to annexed content. Also handles injecting changes to unlocked
files into the annex.
This is meant to be called from git's pre-commit hook. `git annex init`
automatically creates a pre-commit hook using this.
* trust [repository ...]
Records that a repository is [[trusted]] to not unexpectedly lose content.
Use with care.
* untrust [repository ...]
Undoes a trust command.
* fromkey file
This can be used to maually set up a file to link to a specified key
in the key-value backend. How you determine an existing key in the backend
varies. For the URL backend, the key is just a URL to the content.
Example:
git annex fromkey --backend=URL --key=http://www.archive.org/somefile somefile
* dropkey [key ...]
This plumbing-level command drops the annexed data for the specified
keys from this repository.
This can be used to drop content for arbitrary keys, which do not need
to have a file in the git repository pointing at them.
A backend will typically need to be specified with --backend. If none
is specified, the first configured backend is used.
Example:
git annex dropkey --backend=SHA1 7da006579dd64330eb2456001fd01948430572f2
* setkey file
This plumbing-level command sets the annxed data for a key to the content of
the specified file, and then removes the file.
A backend will typically need to be specified with --backend. If none
is specified, the first configured backend is used.
Example:
git annex setkey --backend=WORM --key=1287765018:3 /tmp/file
# OPTIONS
* --force
Force unsafe actions, such as dropping a file's content when no other
source of it can be verified to still exist. Use with care.
* --quiet
Avoid the default verbose logging of what is done; only show errors
and progress displays.
* --verbose
Enable verbose logging.
* --from=repository
Specifies a repository that content will be retrieved from.
It should be specified using the name of a configured git remote.
* --to=repository
Specifies a git repository that content will be sent to.
It should be specified using the name of a configured git remote.
* --exclude=glob
Skips files matching the glob pattern. The glob is matched relative to
the current directory.
* --backend=name
Specifies which key-value backend to use.
* --key=name
Specifies a key to operate on.
# CONFIGURATION
Like other git commands, git-annex is configured via `.git/config`.
Here are all the supported configuration settings.
* `annex.uuid`
A unique UUID for this repository (automatically set).
* `annex.numcopies`
Number of copies of files to keep across all repositories. (default: 1)
* `annex.backends`
Space-separated list of names of the key-value backends to use.
The first listed is used to store new files by default.
(default: "WORM SHA1 URL")
* `remote.<name>.annex-cost`
When determining which repository to
transfer annexed files from or to, ones with lower costs are preferred.
The default cost is 100 for local repositories, and 200 for remote
repositories.
* `remote.<name>.annex-ignore`
If set to `true`, prevents git-annex
from ever using this remote. This is, for example, useful if the
remote is a bare repository, which git-annex does not currently support.
* `remote.<name>.annex-uuid`
git-annex caches UUIDs of repositories here.
* `remote.<name>.annex-scp-options`
Options to use when using scp
to or from this repository. For example, to force ipv6, and limit
the bandwidth to 1000Kbit/s, set it to "-6 -l 1000"
* `remote.<name>.annex-ssh-options`
Options to use when using ssh to talk to this repository.
* `remote.<name>.annex-rsync-options`
Options to use when using rsync
to or from this repository. For example, to force ipv6, and limit
the bandwidth to 100Kbyte/s, set it to "-6 --bwlimit 100"
* `annex.scp-options`, `annex.ssh-options`, `annex.rsync-options`
Default scp, ssh, and rsync options to use if a remote does not have
specific options.
* `annex.version`
Automatically maintained, and used to automate upgrades between versions.
# CONFIGURATION VIA .gitattributes
The backend used when adding a new file to the annex can be configured
on a per-file-type basis via `.gitattributes` files. In the file,
the `annex.backend` attribute can be set to the name of the backend to
use. For example, this here's how to use the WORM backend by default,
but the SHA1 backend for ogg files:
* annex.backend=WORM
*.ogg annex.backend=SHA1
The numcopies setting can also be configured on a per-file-type basis via
the `annex.numcopies` attribute in `.gitattributes` files.
For example, this makes two copies be needed for wav files:
*.wav annex.numcopies=2
# FILES
These files are used by git-annex, in your git repository:
`.git/annex/objects/` contains the annexed file contents that are currently
available. Annexed files in your git repository symlink to that content.
`.git-annex/uuid.log` is used to map between repository UUID and
decscriptions.
`.git-annex/trust.log` is used to list the UUIDs of trusted repositories.
`.git-annex/*.log` is where git-annex records its content tracking
information. These files should be committed to git.
`.gitattributes` is configured to use git's union merge driver
to avoid conflicts when merging files in the `.git-annex` directory.
# SEE ALSO
Most of git-annex's documentation is available on its web site,
<http://git-annex.branchable.com/>
If git-annex is installed from a package, a copy of its documentation
should be included, in, for example, `/usr/share/doc/git-annex/`
# AUTHOR
Joey Hess <joey@kitenet.net>
<http://git-annex.branchable.com/>
Warning: this page is automatically made into a man page via [mdwn2man](http://git.ikiwiki.info/?p=ikiwiki;a=blob;f=mdwn2man;hb=HEAD). Edit with care