githooks

GITHOOKS(5)                        Git Manual                        GITHOOKS(5)



NAME
       githooks - Hooks used by Git

SYNOPSIS
       $GIT_DIR/hooks/* (or `git config core.hooksPath`/*)

DESCRIPTION
       Hooks are programs you can place in a hooks directory to trigger actions
       at certain points in git’s execution. Hooks that don’t have the
       executable bit set are ignored.

       By default the hooks directory is $GIT_DIR/hooks, but that can be changed
       via the core.hooksPath configuration variable (see git-config(1)).

       Before Git invokes a hook, it changes its working directory to either
       $GIT_DIR in a bare repository or the root of the working tree in a
       non-bare repository. An exception are hooks triggered during a push
       (pre-receive, update, post-receive, post-update, push-to-checkout) which
       are always executed in $GIT_DIR.

       Hooks can get their arguments via the environment, command-line
       arguments, and stdin. See the documentation for each hook below for
       details.

       git init may copy hooks to the new repository, depending on its
       configuration. See the "TEMPLATE DIRECTORY" section in git-init(1) for
       details. When the rest of this document refers to "default hooks" it’s
       talking about the default template shipped with Git.

       The currently supported hooks are described below.

HOOKS
   applypatch-msg
       This hook is invoked by git-am(1). It takes a single parameter, the name
       of the file that holds the proposed commit log message. Exiting with a
       non-zero status causes git am to abort before applying the patch.

       The hook is allowed to edit the message file in place, and can be used to
       normalize the message into some project standard format. It can also be
       used to refuse the commit after inspecting the message file.

       The default applypatch-msg hook, when enabled, runs the commit-msg hook,
       if the latter is enabled.

   pre-applypatch
       This hook is invoked by git-am(1). It takes no parameter, and is invoked
       after the patch is applied, but before a commit is made.

       If it exits with non-zero status, then the working tree will not be
       committed after applying the patch.

       It can be used to inspect the current working tree and refuse to make a
       commit if it does not pass certain test.

       The default pre-applypatch hook, when enabled, runs the pre-commit hook,
       if the latter is enabled.

   post-applypatch
       This hook is invoked by git-am(1). It takes no parameter, and is invoked
       after the patch is applied and a commit is made.

       This hook is meant primarily for notification, and cannot affect the
       outcome of git am.

   pre-commit
       This hook is invoked by git-commit(1), and can be bypassed with the
       --no-verify option. It takes no parameters, and is invoked before
       obtaining the proposed commit log message and making a commit. Exiting
       with a non-zero status from this script causes the git commit command to
       abort before creating a commit.

       The default pre-commit hook, when enabled, catches introduction of lines
       with trailing whitespaces and aborts the commit when such a line is
       found.

       All the git commit hooks are invoked with the environment variable
       GIT_EDITOR=: if the command will not bring up an editor to modify the
       commit message.

       The default pre-commit hook, when enabled—and with the
       hooks.allownonascii config option unset or set to false—prevents the use
       of non-ASCII filenames.

   pre-merge-commit
       This hook is invoked by git-merge(1), and can be bypassed with the
       --no-verify option. It takes no parameters, and is invoked after the
       merge has been carried out successfully and before obtaining the proposed
       commit log message to make a commit. Exiting with a non-zero status from
       this script causes the git merge command to abort before creating a
       commit.

       The default pre-merge-commit hook, when enabled, runs the pre-commit
       hook, if the latter is enabled.

       This hook is invoked with the environment variable GIT_EDITOR=: if the
       command will not bring up an editor to modify the commit message.

       If the merge cannot be carried out automatically, the conflicts need to
       be resolved and the result committed separately (see git-merge(1)). At
       that point, this hook will not be executed, but the pre-commit hook will,
       if it is enabled.

   prepare-commit-msg
       This hook is invoked by git-commit(1) right after preparing the default
       log message, and before the editor is started.

       It takes one to three parameters. The first is the name of the file that
       contains the commit log message. The second is the source of the commit
       message, and can be: message (if a -m or -F option was given); template
       (if a -t option was given or the configuration option commit.template is
       set); merge (if the commit is a merge or a .git/MERGE_MSG file exists);
       squash (if a .git/SQUASH_MSG file exists); or commit, followed by a
       commit SHA-1 (if a -c, -C or --amend option was given).

       If the exit status is non-zero, git commit will abort.

       The purpose of the hook is to edit the message file in place, and it is
       not suppressed by the --no-verify option. A non-zero exit means a failure
       of the hook and aborts the commit. It should not be used as replacement
       for pre-commit hook.

       The sample prepare-commit-msg hook that comes with Git removes the help
       message found in the commented portion of the commit template.

   commit-msg
       This hook is invoked by git-commit(1) and git-merge(1), and can be
       bypassed with the --no-verify option. It takes a single parameter, the
       name of the file that holds the proposed commit log message. Exiting with
       a non-zero status causes the command to abort.

       The hook is allowed to edit the message file in place, and can be used to
       normalize the message into some project standard format. It can also be
       used to refuse the commit after inspecting the message file.

       The default commit-msg hook, when enabled, detects duplicate
       Signed-off-by trailers, and aborts the commit if one is found.

   post-commit
       This hook is invoked by git-commit(1). It takes no parameters, and is
       invoked after a commit is made.

       This hook is meant primarily for notification, and cannot affect the
       outcome of git commit.

   pre-rebase
       This hook is called by git-rebase(1) and can be used to prevent a branch
       from getting rebased. The hook may be called with one or two parameters.
       The first parameter is the upstream from which the series was forked. The
       second parameter is the branch being rebased, and is not set when
       rebasing the current branch.

   post-checkout
       This hook is invoked when a git-checkout(1) or git-switch(1) is run after
       having updated the worktree. The hook is given three parameters: the ref
       of the previous HEAD, the ref of the new HEAD (which may or may not have
       changed), and a flag indicating whether the checkout was a branch
       checkout (changing branches, flag=1) or a file checkout (retrieving a
       file from the index, flag=0). This hook cannot affect the outcome of git
       switch or git checkout, other than that the hook’s exit status becomes
       the exit status of these two commands.

       It is also run after git-clone(1), unless the --no-checkout (-n) option
       is used. The first parameter given to the hook is the null-ref, the
       second the ref of the new HEAD and the flag is always 1. Likewise for git
       worktree add unless --no-checkout is used.

       This hook can be used to perform repository validity checks, auto-display
       differences from the previous HEAD if different, or set working dir
       metadata properties.

   post-merge
       This hook is invoked by git-merge(1), which happens when a git pull is
       done on a local repository. The hook takes a single parameter, a status
       flag specifying whether or not the merge being done was a squash merge.
       This hook cannot affect the outcome of git merge and is not executed, if
       the merge failed due to conflicts.

       This hook can be used in conjunction with a corresponding pre-commit hook
       to save and restore any form of metadata associated with the working tree
       (e.g.: permissions/ownership, ACLS, etc). See
       contrib/hooks/setgitperms.perl for an example of how to do this.

   pre-push
       This hook is called by git-push(1) and can be used to prevent a push from
       taking place. The hook is called with two parameters which provide the
       name and location of the destination remote, if a named remote is not
       being used both values will be the same.

       Information about what is to be pushed is provided on the hook’s standard
       input with lines of the form:

           <local ref> SP <local sha1> SP <remote ref> SP <remote sha1> LF

       For instance, if the command git push origin master:foreign were run the
       hook would receive a line like the following:

           refs/heads/master 67890 refs/heads/foreign 12345

       although the full, 40-character SHA-1s would be supplied. If the foreign
       ref does not yet exist the <remote SHA-1> will be 40 0. If a ref is to be
       deleted, the <local ref> will be supplied as (delete) and the <local
       SHA-1> will be 40 0. If the local commit was specified by something other
       than a name which could be expanded (such as HEAD~, or a SHA-1) it will
       be supplied as it was originally given.

       If this hook exits with a non-zero status, git push will abort without
       pushing anything. Information about why the push is rejected may be sent
       to the user by writing to standard error.

   pre-receive
       This hook is invoked by git-receive-pack(1) when it reacts to git push
       and updates reference(s) in its repository. Just before starting to
       update refs on the remote repository, the pre-receive hook is invoked.
       Its exit status determines the success or failure of the update.

       This hook executes once for the receive operation. It takes no arguments,
       but for each ref to be updated it receives on standard input a line of
       the format:

           <old-value> SP <new-value> SP <ref-name> LF

       where <old-value> is the old object name stored in the ref, <new-value>
       is the new object name to be stored in the ref and <ref-name> is the full
       name of the ref. When creating a new ref, <old-value> is 40 0.

       If the hook exits with non-zero status, none of the refs will be updated.
       If the hook exits with zero, updating of individual refs can still be
       prevented by the update hook.

       Both standard output and standard error output are forwarded to git
       send-pack on the other end, so you can simply echo messages for the user.

       The number of push options given on the command line of git push
       --push-option=... can be read from the environment variable
       GIT_PUSH_OPTION_COUNT, and the options themselves are found in
       GIT_PUSH_OPTION_0, GIT_PUSH_OPTION_1,... If it is negotiated to not use
       the push options phase, the environment variables will not be set. If the
       client selects to use push options, but doesn’t transmit any, the count
       variable will be set to zero, GIT_PUSH_OPTION_COUNT=0.

       See the section on "Quarantine Environment" in git-receive-pack(1) for
       some caveats.

   update
       This hook is invoked by git-receive-pack(1) when it reacts to git push
       and updates reference(s) in its repository. Just before updating the ref
       on the remote repository, the update hook is invoked. Its exit status
       determines the success or failure of the ref update.

       The hook executes once for each ref to be updated, and takes three
       parameters:

       •   the name of the ref being updated,

       •   the old object name stored in the ref,

       •   and the new object name to be stored in the ref.

       A zero exit from the update hook allows the ref to be updated. Exiting
       with a non-zero status prevents git receive-pack from updating that ref.

       This hook can be used to prevent forced update on certain refs by making
       sure that the object name is a commit object that is a descendant of the
       commit object named by the old object name. That is, to enforce a
       "fast-forward only" policy.

       It could also be used to log the old..new status. However, it does not
       know the entire set of branches, so it would end up firing one e-mail per
       ref when used naively, though. The post-receive hook is more suited to
       that.

       In an environment that restricts the users' access only to git commands
       over the wire, this hook can be used to implement access control without
       relying on filesystem ownership and group membership. See git-shell(1)
       for how you might use the login shell to restrict the user’s access to
       only git commands.

       Both standard output and standard error output are forwarded to git
       send-pack on the other end, so you can simply echo messages for the user.

       The default update hook, when enabled—and with hooks.allowunannotated
       config option unset or set to false—prevents unannotated tags to be
       pushed.

   proc-receive
       This hook is invoked by git-receive-pack(1). If the server has set the
       multi-valued config variable receive.procReceiveRefs, and the commands
       sent to receive-pack have matching reference names, these commands will
       be executed by this hook, instead of by the internal execute_commands()
       function. This hook is responsible for updating the relevant references
       and reporting the results back to receive-pack.

       This hook executes once for the receive operation. It takes no arguments,
       but uses a pkt-line format protocol to communicate with receive-pack to
       read commands, push-options and send results. In the following example
       for the protocol, the letter S stands for receive-pack and the letter H
       stands for this hook.

           # Version and features negotiation.
           S: PKT-LINE(version=1\0push-options atomic...)
           S: flush-pkt
           H: PKT-LINE(version=1\0push-options...)
           H: flush-pkt

           # Send commands from server to the hook.
           S: PKT-LINE(<old-oid> <new-oid> <ref>)
           S: ... ...
           S: flush-pkt
           # Send push-options only if the 'push-options' feature is enabled.
           S: PKT-LINE(push-option)
           S: ... ...
           S: flush-pkt

           # Receive result from the hook.
           # OK, run this command successfully.
           H: PKT-LINE(ok <ref>)
           # NO, I reject it.
           H: PKT-LINE(ng <ref> <reason>)
           # Fall through, let 'receive-pack' to execute it.
           H: PKT-LINE(ok <ref>)
           H: PKT-LINE(option fall-through)
           # OK, but has an alternate reference.  The alternate reference name
           # and other status can be given in option directives.
           H: PKT-LINE(ok <ref>)
           H: PKT-LINE(option refname <refname>)
           H: PKT-LINE(option old-oid <old-oid>)
           H: PKT-LINE(option new-oid <new-oid>)
           H: PKT-LINE(option forced-update)
           H: ... ...
           H: flush-pkt

       Each command for the proc-receive hook may point to a pseudo-reference
       and always has a zero-old as its old-oid, while the proc-receive hook may
       update an alternate reference and the alternate reference may exist
       already with a non-zero old-oid. For this case, this hook will use
       "option" directives to report extended attributes for the reference given
       by the leading "ok" directive.

       The report of the commands of this hook should have the same order as the
       input. The exit status of the proc-receive hook only determines the
       success or failure of the group of commands sent to it, unless atomic
       push is in use.

   post-receive
       This hook is invoked by git-receive-pack(1) when it reacts to git push
       and updates reference(s) in its repository. It executes on the remote
       repository once after all the refs have been updated.

       This hook executes once for the receive operation. It takes no arguments,
       but gets the same information as the pre-receive hook does on its
       standard input.

       This hook does not affect the outcome of git receive-pack, as it is
       called after the real work is done.

       This supersedes the post-update hook in that it gets both old and new
       values of all the refs in addition to their names.

       Both standard output and standard error output are forwarded to git
       send-pack on the other end, so you can simply echo messages for the user.

       The default post-receive hook is empty, but there is a sample script
       post-receive-email provided in the contrib/hooks directory in Git
       distribution, which implements sending commit emails.

       The number of push options given on the command line of git push
       --push-option=... can be read from the environment variable
       GIT_PUSH_OPTION_COUNT, and the options themselves are found in
       GIT_PUSH_OPTION_0, GIT_PUSH_OPTION_1,... If it is negotiated to not use
       the push options phase, the environment variables will not be set. If the
       client selects to use push options, but doesn’t transmit any, the count
       variable will be set to zero, GIT_PUSH_OPTION_COUNT=0.

   post-update
       This hook is invoked by git-receive-pack(1) when it reacts to git push
       and updates reference(s) in its repository. It executes on the remote
       repository once after all the refs have been updated.

       It takes a variable number of parameters, each of which is the name of
       ref that was actually updated.

       This hook is meant primarily for notification, and cannot affect the
       outcome of git receive-pack.

       The post-update hook can tell what are the heads that were pushed, but it
       does not know what their original and updated values are, so it is a poor
       place to do log old..new. The post-receive hook does get both original
       and updated values of the refs. You might consider it instead if you need
       them.

       When enabled, the default post-update hook runs git update-server-info to
       keep the information used by dumb transports (e.g., HTTP) up to date. If
       you are publishing a Git repository that is accessible via HTTP, you
       should probably enable this hook.

       Both standard output and standard error output are forwarded to git
       send-pack on the other end, so you can simply echo messages for the user.

   reference-transaction
       This hook is invoked by any Git command that performs reference updates.
       It executes whenever a reference transaction is prepared, committed or
       aborted and may thus get called multiple times.

       The hook takes exactly one argument, which is the current state the given
       reference transaction is in:

       •   "prepared": All reference updates have been queued to the transaction
           and references were locked on disk.

       •   "committed": The reference transaction was committed and all
           references now have their respective new value.

       •   "aborted": The reference transaction was aborted, no changes were
           performed and the locks have been released.

       For each reference update that was added to the transaction, the hook
       receives on standard input a line of the format:

           <old-value> SP <new-value> SP <ref-name> LF

       The exit status of the hook is ignored for any state except for the
       "prepared" state. In the "prepared" state, a non-zero exit status will
       cause the transaction to be aborted. The hook will not be called with
       "aborted" state in that case.

   push-to-checkout
       This hook is invoked by git-receive-pack(1) when it reacts to git push
       and updates reference(s) in its repository, and when the push tries to
       update the branch that is currently checked out and the
       receive.denyCurrentBranch configuration variable is set to updateInstead.
       Such a push by default is refused if the working tree and the index of
       the remote repository has any difference from the currently checked out
       commit; when both the working tree and the index match the current
       commit, they are updated to match the newly pushed tip of the branch.
       This hook is to be used to override the default behaviour.

       The hook receives the commit with which the tip of the current branch is
       going to be updated. It can exit with a non-zero status to refuse the
       push (when it does so, it must not modify the index or the working tree).
       Or it can make any necessary changes to the working tree and to the index
       to bring them to the desired state when the tip of the current branch is
       updated to the new commit, and exit with a zero status.

       For example, the hook can simply run git read-tree -u -m HEAD "$1" in
       order to emulate git fetch that is run in the reverse direction with git
       push, as the two-tree form of git read-tree -u -m is essentially the same
       as git switch or git checkout that switches branches while keeping the
       local changes in the working tree that do not interfere with the
       difference between the branches.

   pre-auto-gc
       This hook is invoked by git gc --auto (see git-gc(1)). It takes no
       parameter, and exiting with non-zero status from this script causes the
       git gc --auto to abort.

   post-rewrite
       This hook is invoked by commands that rewrite commits (git-commit(1) when
       called with --amend and git-rebase(1); however, full-history (re)writing
       tools like git-fast-import(1) or git-filter-repo[1] typically do not call
       it!). Its first argument denotes the command it was invoked by: currently
       one of amend or rebase. Further command-dependent arguments may be passed
       in the future.

       The hook receives a list of the rewritten commits on stdin, in the format

           <old-sha1> SP <new-sha1> [ SP <extra-info> ] LF

       The extra-info is again command-dependent. If it is empty, the preceding
       SP is also omitted. Currently, no commands pass any extra-info.

       The hook always runs after the automatic note copying (see
       "notes.rewrite.<command>" in git-config(1)) has happened, and thus has
       access to these notes.

       The following command-specific comments apply:

       rebase
           For the squash and fixup operation, all commits that were squashed
           are listed as being rewritten to the squashed commit. This means that
           there will be several lines sharing the same new-sha1.

           The commits are guaranteed to be listed in the order that they were
           processed by rebase.

   sendemail-validate
       This hook is invoked by git-send-email(1). It takes a single parameter,
       the name of the file that holds the e-mail to be sent. Exiting with a
       non-zero status causes git send-email to abort before sending any
       e-mails.

   fsmonitor-watchman
       This hook is invoked when the configuration option core.fsmonitor is set
       to .git/hooks/fsmonitor-watchman or .git/hooks/fsmonitor-watchmanv2
       depending on the version of the hook to use.

       Version 1 takes two arguments, a version (1) and the time in elapsed
       nanoseconds since midnight, January 1, 1970.

       Version 2 takes two arguments, a version (2) and a token that is used for
       identifying changes since the token. For watchman this would be a clock
       id. This version must output to stdout the new token followed by a NUL
       before the list of files.

       The hook should output to stdout the list of all files in the working
       directory that may have changed since the requested time. The logic
       should be inclusive so that it does not miss any potential changes. The
       paths should be relative to the root of the working directory and be
       separated by a single NUL.

       It is OK to include files which have not actually changed. All changes
       including newly-created and deleted files should be included. When files
       are renamed, both the old and the new name should be included.

       Git will limit what files it checks for changes as well as which
       directories are checked for untracked files based on the path names
       given.

       An optimized way to tell git "all files have changed" is to return the
       filename /.

       The exit status determines whether git will use the data from the hook to
       limit its search. On error, it will fall back to verifying all files and
       folders.

   p4-changelist
       This hook is invoked by git-p4 submit.

       The p4-changelist hook is executed after the changelist message has been
       edited by the user. It can be bypassed with the --no-verify option. It
       takes a single parameter, the name of the file that holds the proposed
       changelist text. Exiting with a non-zero status causes the command to
       abort.

       The hook is allowed to edit the changelist file and can be used to
       normalize the text into some project standard format. It can also be used
       to refuse the Submit after inspect the message file.

       Run git-p4 submit --help for details.

   p4-prepare-changelist
       This hook is invoked by git-p4 submit.

       The p4-prepare-changelist hook is executed right after preparing the
       default changelist message and before the editor is started. It takes one
       parameter, the name of the file that contains the changelist text.
       Exiting with a non-zero status from the script will abort the process.

       The purpose of the hook is to edit the message file in place, and it is
       not supressed by the --no-verify option. This hook is called even if
       --prepare-p4-only is set.

       Run git-p4 submit --help for details.

   p4-post-changelist
       This hook is invoked by git-p4 submit.

       The p4-post-changelist hook is invoked after the submit has successfully
       occurred in P4. It takes no parameters and is meant primarily for
       notification and cannot affect the outcome of the git p4 submit action.

       Run git-p4 submit --help for details.

   p4-pre-submit
       This hook is invoked by git-p4 submit. It takes no parameters and nothing
       from standard input. Exiting with non-zero status from this script
       prevent git-p4 submit from launching. It can be bypassed with the
       --no-verify command line option. Run git-p4 submit --help for details.

   post-index-change
       This hook is invoked when the index is written in read-cache.c
       do_write_locked_index.

       The first parameter passed to the hook is the indicator for the working
       directory being updated. "1" meaning working directory was updated or "0"
       when the working directory was not updated.

       The second parameter passed to the hook is the indicator for whether or
       not the index was updated and the skip-worktree bit could have changed.
       "1" meaning skip-worktree bits could have been updated and "0" meaning
       they were not.

       Only one parameter should be set to "1" when the hook runs. The hook
       running passing "1", "1" should not be possible.

GIT
       Part of the git(1) suite

NOTES
        1. git-filter-repo
           https://github.com/newren/git-filter-repo



Git 2.30.0                         12/28/2020                        GITHOOKS(5)