git-annex-preferred-content(1)
NAME
git-annex-preferred-content - which files are wanted in a repository
DESCRIPTION
Each repository has a preferred content setting, which specifies content that the repository wants to have present. These settings can be configured using git annex vicfg or git annex wanted. They are used by the --auto option, by git annex sync --content, and by the git-annex assistant. While preferred content expresses a preference, it can be overridden by simply using git annex drop. On the other hand, required content settings are enforced; git annex drop will refuse to drop a file if doing so would violate its required content settings. A repository's required content can be configured using git annex vicfg or git annex required.
SYNTAX
Preferred content expressions use a similar syntax to the git-
annex-matching-options(1), without the dashes. For example:
exclude=archive/* and (include=*.mp3 or smallerthan=1mb)
The idea is that you write an expression that files are matched
against. If a file matches, the repository wants to store its content.
If it doesn't, the repository wants to drop its content (if there are
enough copies elsewhere to allow removing it).
EXPRESSIONS
include=glob / exclude=glob
Match files to include, or exclude.
While --include=glob and --exclude=glob match files relative to
the current directory, preferred content expressions always
match files relative to the top of the git repository.
For example, suppose you put files into archive directories when
you're done with them. Then you could configure your laptop to
prefer to not retain those files, like this: exclude=*/archive/*
copies=number
Matches only files that git-annex believes to have the specified
number of copies, or more. Note that it does not check remotes
to verify that the copies still exist.
To decide if content should be dropped, git-annex evaluates the
preferred content expression under the assumption that the
content has *already* been dropped. If the content would not be
wanted then, the drop can be done. So, for example, copies=2 in
a preferred content expression lets content be dropped only when
there are currently 3 copies of it, including the repo it's
being dropped from. This is different than running git annex
drop --copies=2, which will drop files that currently have 2
copies.
copies=trustlevel:number
Matches only files that git-annex believes have the specified
number copies, on remotes with the specified trust level. For
example, copies=trusted:2
To match any trust level at or higher than a given level, use
trustlevel+. For example, copies=semitrusted+:2
copies=groupname:number
Matches only files that git-annex believes have the specified
number of copies, on remotes in the specified group. For
example, copies=archive:2
Preferred content expressions have no equivalent to the --in
option, but groups can accomplish similar things. You can add
repositories to groups, and match against the groups in a
preferred content expression. So rather than --in=usbdrive, put
all the USB drives into a "transfer" group, and use
copies=transfer:1
lackingcopies=number
Matches only files that git-annex believes need the specified
number or more additional copies to be made in order to satisfy
their numcopies settings.
approxlackingcopies=number
Like lackingcopies, but does not look at .gitattributes
annex.numcopies settings. This makes it significantly faster.
inbackend=name
Matches only files whose content is stored using the specified
key-value backend.
inallgroup=groupname
Matches only files that git-annex believes are present in all
repositories in the specified group.
smallerthan=size / largerthan=size
Matches only files whose content is smaller than, or larger than
the specified size.
The size can be specified with any commonly used units, for
example, "0.5 gb" or "100 KiloBytes"
metadata=field=glob
Matches only files that have a metadata field attached with a
value that matches the glob. The values of metadata fields are
matched case insensitively.
To match a tag "done", use metadata=tag=done
To match author metadata, use metadata=author=*Smith
metadata=field<number / metadata=field>number
metadata=field<=number / metadata=field>=number
Matches only files that have a metadata field attached with a
value that is a number and is less than or greater than the
specified number.
To match PDFs with between 100 and 200 pages (assuming something
has set that metadata), use metadata=pagecount>=100 and
metadata=pagecount<=200
present
Makes content be wanted if it's present, but not otherwise.
This leaves it up to you to use git-annex manually to move
content around. You can use this to avoid preferred content
settings from affecting a subdirectory. For example: auto/* or
(include=ad-hoc/* and present)
Note that not present is a very bad thing to put in a preferred
content expression. It'll make it want to get content that's not
present, and drop content that is present! Don't go there..
inpreferreddir
Makes content be preferred if it's in a directory (located
anywhere in the tree) with a particular name.
The name of the directory can be configured using git annex
enableremote $remote preferreddir=$dirname
(If no directory name is configured, it uses "public" by
default.)
standard
git-annex comes with some built-in preferred content
expressions, that can be used with repositories that are in some
[[preferred content/standard groups/]].
When a repository is in exactly one such group, you can use the
"standard" keyword in its preferred content expression, to match
whatever content the group's expression matches. (If a
repository is put into multiple standard groups, "standard" will
match anything.. so don't do that!)
Most often, the whole preferred content expression is simply
"standard". But, you can do more complicated things, for
example: standard or include=otherdir/*
groupwanted
The "groupwanted" keyword can be used to refer to a preferred
content expression that is associated with a group. This is like
the "standard" keyword, but you can configure the preferred
content expressions using git annex groupwanted.
Note that when writing a groupwanted preferred content
expression, you can use all of the keywords listed above,
including "standard". (But not "groupwanted".)
For example, to make a variant of the standard client preferred
content expression that does not want files in the "out"
directory, you could run: git annex groupwanted client "standard
and exclude=out/*"
Then repositories that are in the client group and have their
preferred content expression set to "groupwanted" will use that,
while other client repositories that have their preferred
content expression set to "standard" will use the standard
expression.
Or, you could make a new group, with your own custom preferred
content expression tuned for your needs, and every repository
you put in this group and make its preferred content be
"groupwanted" will use it.
For example, the archive group only wants to archive 1 copy of
each file, spread among every repository in the group. Here's
how to configure a group named redundantarchive, that instead
wants to contain 3 copies of each file:
git annex groupwanted redundantarchive "not
(copies=redundantarchive:3)"
for repo in foo bar baz; do
git annex group $repo redundantarchive
git annex wanted $repo groupwanted
done
unused Matches only keys that git annex unused has determined to be
unused.
This is related the the --unused option. However, putting
unused in a preferred content expression doesn't make git-annex
consider those unused keys. So when git-annex is only checking
preferred content expressions against files in the repository
(which are obviously used), unused in a preferred content
expression won't match anything.
So when is unused useful in a preferred content expression?
Using git annex sync --content --all will operate on all files,
including unused ones, and take unused in preferred content
expressions into account.
The git-annex assistant periodically scans for unused files, and
moves them to some repository whose preferred content expression
says it wants them. (Or, if annex.expireunused is set, it may
just delete them.)
anything
Always matches.
nothing
Never matches. (Same as "not anything")
not expression
Inverts what the expression matches. For example, not
include=archive/* is the same as exclude=archive/*
and / or / ( expression )
These can be used to build up more complicated expressions.
TESTING
To check at the command line which files are matched by a repository's preferred content settings, you can use the --want-get and --want-drop options. For example, git annex find --want-get --not --in . will find all the files that git annex get --auto will want to get, and git annex find --want-drop --in . will find all the files that git annex drop --auto will want to drop.
SEE ALSO
git-annex(1) git-annex-vicfg(1) git-annex-wanted(1) <https://git-annex.branchable.com/preferred_content/>
AUTHOR
Joey Hess <[email protected]> <http://git-annex.branchable.com/> git-annex-preferred-content(1)
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