git-submodule(1)
NAME
git-submodule - Initialize, update or inspect submodules
SYNOPSIS
git submodule [--quiet] add [-b <branch>] [-f|--force] [--name <name>]
[--reference <repository>] [--depth <depth>] [--] <repository> [<path>]
git submodule [--quiet] status [--cached] [--recursive] [--] [<path>...]
git submodule [--quiet] init [--] [<path>...]
git submodule [--quiet] deinit [-f|--force] (--all|[--] <path>...)
git submodule [--quiet] update [--init] [--remote] [-N|--no-fetch]
[--[no-]recommend-shallow] [-f|--force] [--rebase|--merge]
[--reference <repository>] [--depth <depth>] [--recursive]
[--jobs <n>] [--] [<path>...]
git submodule [--quiet] summary [--cached|--files] [(-n|--summary-limit) <n>]
[commit] [--] [<path>...]
git submodule [--quiet] foreach [--recursive] <command>
git submodule [--quiet] sync [--recursive] [--] [<path>...]
DESCRIPTION
Inspects, updates and manages submodules. A submodule allows you to keep another Git repository in a subdirectory of your repository. The other repository has its own history, which does not interfere with the history of the current repository. This can be used to have external dependencies such as third party libraries for example. When cloning or pulling a repository containing submodules however, these will not be checked out by default; the init and update subcommands will maintain submodules checked out and at appropriate revision in your working tree. Submodules are composed from a so-called gitlink tree entry in the main repository that refers to a particular commit object within the inner repository that is completely separate. A record in the .gitmodules (see gitmodules(5)) file at the root of the source tree assigns a logical name to the submodule and describes the default URL the submodule shall be cloned from. The logical name can be used for overriding this URL within your local repository configuration (see submodule init). Submodules are not to be confused with remotes, which are other repositories of the same project; submodules are meant for different projects you would like to make part of your source tree, while the history of the two projects still stays completely independent and you cannot modify the contents of the submodule from within the main project. If you want to merge the project histories and want to treat the aggregated whole as a single project from then on, you may want to add a remote for the other project and use the subtree merge strategy, instead of treating the other project as a submodule. Directories that come from both projects can be cloned and checked out as a whole if you choose to go that route.
COMMANDS
add
Add the given repository as a submodule at the given path to the
changeset to be committed next to the current project: the current
project is termed the "superproject".
This requires at least one argument: <repository>. The optional
argument <path> is the relative location for the cloned submodule
to exist in the superproject. If <path> is not given, the
"humanish" part of the source repository is used ("repo" for
"/path/to/repo.git" and "foo" for "host.xz:foo/.git"). The <path>
is also used as the submodule's logical name in its configuration
entries unless --name is used to specify a logical name.
<repository> is the URL of the new submodule's origin repository.
This may be either an absolute URL, or (if it begins with ./ or
../), the location relative to the superproject's origin repository
(Please note that to specify a repository foo.git which is located
right next to a superproject bar.git, you'll have to use ../foo.git
instead of ./foo.git - as one might expect when following the rules
for relative URLs - because the evaluation of relative URLs in Git
is identical to that of relative directories). If the superproject
doesn't have an origin configured the superproject is its own
authoritative upstream and the current working directory is used
instead.
<path> is the relative location for the cloned submodule to exist
in the superproject. If <path> does not exist, then the submodule
is created by cloning from the named URL. If <path> does exist and
is already a valid Git repository, then this is added to the
changeset without cloning. This second form is provided to ease
creating a new submodule from scratch, and presumes the user will
later push the submodule to the given URL.
In either case, the given URL is recorded into .gitmodules for use
by subsequent users cloning the superproject. If the URL is given
relative to the superproject's repository, the presumption is the
superproject and submodule repositories will be kept together in
the same relative location, and only the superproject's URL needs
to be provided: git-submodule will correctly locate the submodule
using the relative URL in .gitmodules.
status
Show the status of the submodules. This will print the SHA-1 of the
currently checked out commit for each submodule, along with the
submodule path and the output of git describe for the SHA-1. Each
SHA-1 will be prefixed with - if the submodule is not initialized,
+ if the currently checked out submodule commit does not match the
SHA-1 found in the index of the containing repository and U if the
submodule has merge conflicts.
If --recursive is specified, this command will recurse into nested
submodules, and show their status as well.
If you are only interested in changes of the currently initialized
submodules with respect to the commit recorded in the index or the
HEAD, git-status(1) and git-diff(1) will provide that information
too (and can also report changes to a submodule's work tree).
init
Initialize the submodules recorded in the index (which were added
and committed elsewhere) by copying submodule names and urls from
.gitmodules to .git/config. Optional <path> arguments limit which
submodules will be initialized. It will also copy the value of
submodule.$name.update into .git/config. The key used in
.git/config is submodule.$name.url. This command does not alter
existing information in .git/config. You can then customize the
submodule clone URLs in .git/config for your local setup and
proceed to git submodule update; you can also just use git
submodule update --init without the explicit init step if you do
not intend to customize any submodule locations.
deinit
Unregister the given submodules, i.e. remove the whole
submodule.$name section from .git/config together with their work
tree. Further calls to git submodule update, git submodule foreach
and git submodule sync will skip any unregistered submodules until
they are initialized again, so use this command if you don't want
to have a local checkout of the submodule in your working tree
anymore. If you really want to remove a submodule from the
repository and commit that use git-rm(1) instead.
When the command is run without pathspec, it errors out, instead of
deinit-ing everything, to prevent mistakes.
If --force is specified, the submodule's working tree will be
removed even if it contains local modifications.
update
Update the registered submodules to match what the superproject
expects by cloning missing submodules and updating the working tree
of the submodules. The "updating" can be done in several ways
depending on command line options and the value of
submodule.<name>.update configuration variable. Supported update
procedures are:
checkout
the commit recorded in the superproject will be checked out in
the submodule on a detached HEAD. This is done when --checkout
option is given, or no option is given, and
submodule.<name>.update is unset, or if it is set to checkout.
If --force is specified, the submodule will be checked out
(using git checkout --force if appropriate), even if the commit
specified in the index of the containing repository already
matches the commit checked out in the submodule.
rebase
the current branch of the submodule will be rebased onto the
commit recorded in the superproject. This is done when --rebase
option is given, or no option is given, and
submodule.<name>.update is set to rebase.
merge
the commit recorded in the superproject will be merged into the
current branch in the submodule. This is done when --merge
option is given, or no option is given, and
submodule.<name>.update is set to merge.
custom command
arbitrary shell command that takes a single argument (the sha1
of the commit recorded in the superproject) is executed. This
is done when no option is given, and submodule.<name>.update
has the form of !command.
When no option is given and submodule.<name>.update is set to none,
the submodule is not updated.
If the submodule is not yet initialized, and you just want to use
the setting as stored in .gitmodules, you can automatically
initialize the submodule with the --init option.
If --recursive is specified, this command will recurse into the
registered submodules, and update any nested submodules within.
summary
Show commit summary between the given commit (defaults to HEAD) and
working tree/index. For a submodule in question, a series of
commits in the submodule between the given super project commit and
the index or working tree (switched by --cached) are shown. If the
option --files is given, show the series of commits in the
submodule between the index of the super project and the working
tree of the submodule (this option doesn't allow to use the
--cached option or to provide an explicit commit).
Using the --submodule=log option with git-diff(1) will provide that
information too.
foreach
Evaluates an arbitrary shell command in each checked out submodule.
The command has access to the variables $name, $path, $sha1 and
$toplevel: $name is the name of the relevant submodule section in
.gitmodules, $path is the name of the submodule directory relative
to the superproject, $sha1 is the commit as recorded in the
superproject, and $toplevel is the absolute path to the top-level
of the superproject. Any submodules defined in the superproject but
not checked out are ignored by this command. Unless given --quiet,
foreach prints the name of each submodule before evaluating the
command. If --recursive is given, submodules are traversed
recursively (i.e. the given shell command is evaluated in nested
submodules as well). A non-zero return from the command in any
submodule causes the processing to terminate. This can be
overridden by adding || : to the end of the command.
As an example, git submodule foreach 'echo $path `git rev-parse
HEAD`' will show the path and currently checked out commit for each
submodule.
sync
Synchronizes submodules' remote URL configuration setting to the
value specified in .gitmodules. It will only affect those
submodules which already have a URL entry in .git/config (that is
the case when they are initialized or freshly added). This is
useful when submodule URLs change upstream and you need to update
your local repositories accordingly.
"git submodule sync" synchronizes all submodules while "git
submodule sync -- A" synchronizes submodule "A" only.
If --recursive is specified, this command will recurse into the
registered submodules, and sync any nested submodules within.
OPTIONS
-q, --quiet
Only print error messages.
--all
This option is only valid for the deinit command. Unregister all
submodules in the working tree.
-b, --branch
Branch of repository to add as submodule. The name of the branch is
recorded as submodule.<name>.branch in .gitmodules for update
--remote. A special value of . is used to indicate that the name
of the branch in the submodule should be the same name as the
current branch in the current repository.
-f, --force
This option is only valid for add, deinit and update commands. When
running add, allow adding an otherwise ignored submodule path. When
running deinit the submodule working trees will be removed even if
they contain local changes. When running update (only effective
with the checkout procedure), throw away local changes in
submodules when switching to a different commit; and always run a
checkout operation in the submodule, even if the commit listed in
the index of the containing repository matches the commit checked
out in the submodule.
--cached
This option is only valid for status and summary commands. These
commands typically use the commit found in the submodule HEAD, but
with this option, the commit stored in the index is used instead.
--files
This option is only valid for the summary command. This command
compares the commit in the index with that in the submodule HEAD
when this option is used.
-n, --summary-limit
This option is only valid for the summary command. Limit the
summary size (number of commits shown in total). Giving 0 will
disable the summary; a negative number means unlimited (the
default). This limit only applies to modified submodules. The size
is always limited to 1 for added/deleted/typechanged submodules.
--remote
This option is only valid for the update command. Instead of using
the superproject's recorded SHA-1 to update the submodule, use the
status of the submodule's remote-tracking branch. The remote used
is branch's remote (branch.<name>.remote), defaulting to origin.
The remote branch used defaults to master, but the branch name may
be overridden by setting the submodule.<name>.branch option in
either .gitmodules or .git/config (with .git/config taking
precedence).
This works for any of the supported update procedures (--checkout,
--rebase, etc.). The only change is the source of the target SHA-1.
For example, submodule update --remote --merge will merge upstream
submodule changes into the submodules, while submodule update
--merge will merge superproject gitlink changes into the
submodules.
In order to ensure a current tracking branch state, update --remote
fetches the submodule's remote repository before calculating the
SHA-1. If you don't want to fetch, you should use submodule update
--remote --no-fetch.
Use this option to integrate changes from the upstream subproject
with your submodule's current HEAD. Alternatively, you can run git
pull from the submodule, which is equivalent except for the remote
branch name: update --remote uses the default upstream repository
and submodule.<name>.branch, while git pull uses the submodule's
branch.<name>.merge. Prefer submodule.<name>.branch if you want to
distribute the default upstream branch with the superproject and
branch.<name>.merge if you want a more native feel while working in
the submodule itself.
-N, --no-fetch
This option is only valid for the update command. Don't fetch new
objects from the remote site.
--checkout
This option is only valid for the update command. Checkout the
commit recorded in the superproject on a detached HEAD in the
submodule. This is the default behavior, the main use of this
option is to override submodule.$name.update when set to a value
other than checkout. If the key submodule.$name.update is either
not explicitly set or set to checkout, this option is implicit.
--merge
This option is only valid for the update command. Merge the commit
recorded in the superproject into the current branch of the
submodule. If this option is given, the submodule's HEAD will not
be detached. If a merge failure prevents this process, you will
have to resolve the resulting conflicts within the submodule with
the usual conflict resolution tools. If the key
submodule.$name.update is set to merge, this option is implicit.
--rebase
This option is only valid for the update command. Rebase the
current branch onto the commit recorded in the superproject. If
this option is given, the submodule's HEAD will not be detached. If
a merge failure prevents this process, you will have to resolve
these failures with git-rebase(1). If the key
submodule.$name.update is set to rebase, this option is implicit.
--init
This option is only valid for the update command. Initialize all
submodules for which "git submodule init" has not been called so
far before updating.
--name
This option is only valid for the add command. It sets the
submodule's name to the given string instead of defaulting to its
path. The name must be valid as a directory name and may not end
with a /.
--reference <repository>
This option is only valid for add and update commands. These
commands sometimes need to clone a remote repository. In this case,
this option will be passed to the git-clone(1) command.
NOTE: Do not use this option unless you have read the note for git-
clone(1)'s --reference and --shared options carefully.
--recursive
This option is only valid for foreach, update, status and sync
commands. Traverse submodules recursively. The operation is
performed not only in the submodules of the current repo, but also
in any nested submodules inside those submodules (and so on).
--depth
This option is valid for add and update commands. Create a shallow
clone with a history truncated to the specified number of
revisions. See git-clone(1)
--[no-]recommend-shallow
This option is only valid for the update command. The initial clone
of a submodule will use the recommended submodule.<name>.shallow as
provided by the .gitmodules file by default. To ignore the
suggestions use --no-recommend-shallow.
-j <n>, --jobs <n>
This option is only valid for the update command. Clone new
submodules in parallel with as many jobs. Defaults to the
submodule.fetchJobs option.
<path>...
Paths to submodule(s). When specified this will restrict the
command to only operate on the submodules found at the specified
paths. (This argument is required with add).
FILES
When initializing submodules, a .gitmodules file in the top-level directory of the containing repository is used to find the url of each submodule. This file should be formatted in the same way as $GIT_DIR/config. The key to each submodule url is "submodule.$name.url". See gitmodules(5) for details.
GIT
Part of the git(1) suite
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