1githooks(5) 2=========== 3 4NAME 5---- 6githooks - Hooks used by Git 7 8SYNOPSIS 9-------- 10$GIT_DIR/hooks/* 11 12 13DESCRIPTION 14----------- 15 16Hooks are little scripts you can place in `$GIT_DIR/hooks` 17directory to trigger action at certain points. When 18'git init' is run, a handful of example hooks are copied into the 19`hooks` directory of the new repository, but by default they are 20all disabled. To enable a hook, rename it by removing its `.sample` 21suffix. 22 23NOTE: It is also a requirement for a given hook to be executable. 24However - in a freshly initialized repository - the `.sample` files are 25executable by default. 26 27This document describes the currently defined hooks. 28 29HOOKS 30----- 31 32applypatch-msg 33~~~~~~~~~~~~~~ 34 35This hook is invoked by 'git am' script. It takes a single 36parameter, the name of the file that holds the proposed commit 37log message. Exiting with non-zero status causes 38'git am' to abort before applying the patch. 39 40The hook is allowed to edit the message file in place, and can 41be used to normalize the message into some project standard 42format (if the project has one). It can also be used to refuse 43the commit after inspecting the message file. 44 45The default 'applypatch-msg' hook, when enabled, runs the 46'commit-msg' hook, if the latter is enabled. 47 48pre-applypatch 49~~~~~~~~~~~~~~ 50 51This hook is invoked by 'git am'. It takes no parameter, and is 52invoked after the patch is applied, but before a commit is made. 53 54If it exits with non-zero status, then the working tree will not be 55committed after applying the patch. 56 57It can be used to inspect the current working tree and refuse to 58make a commit if it does not pass certain test. 59 60The default 'pre-applypatch' hook, when enabled, runs the 61'pre-commit' hook, if the latter is enabled. 62 63post-applypatch 64~~~~~~~~~~~~~~~ 65 66This hook is invoked by 'git am'. It takes no parameter, 67and is invoked after the patch is applied and a commit is made. 68 69This hook is meant primarily for notification, and cannot affect 70the outcome of 'git am'. 71 72pre-commit 73~~~~~~~~~~ 74 75This hook is invoked by 'git commit', and can be bypassed 76with `--no-verify` option. It takes no parameter, and is 77invoked before obtaining the proposed commit log message and 78making a commit. Exiting with non-zero status from this script 79causes the 'git commit' to abort. 80 81The default 'pre-commit' hook, when enabled, catches introduction 82of lines with trailing whitespaces and aborts the commit when 83such a line is found. 84 85All the 'git commit' hooks are invoked with the environment 86variable `GIT_EDITOR=:` if the command will not bring up an editor 87to modify the commit message. 88 89prepare-commit-msg 90~~~~~~~~~~~~~~~~~~ 91 92This hook is invoked by 'git commit' right after preparing the 93default log message, and before the editor is started. 94 95It takes one to three parameters. The first is the name of the file 96that contains the commit log message. The second is the source of the commit 97message, and can be: `message` (if a `-m` or `-F` option was 98given); `template` (if a `-t` option was given or the 99configuration option `commit.template` is set); `merge` (if the 100commit is a merge or a `.git/MERGE_MSG` file exists); `squash` 101(if a `.git/SQUASH_MSG` file exists); or `commit`, followed by 102a commit SHA-1 (if a `-c`, `-C` or `--amend` option was given). 103 104If the exit status is non-zero, 'git commit' will abort. 105 106The purpose of the hook is to edit the message file in place, and 107it is not suppressed by the `--no-verify` option. A non-zero exit 108means a failure of the hook and aborts the commit. It should not 109be used as replacement for pre-commit hook. 110 111The sample `prepare-commit-msg` hook that comes with Git comments 112out the `Conflicts:` part of a merge's commit message. 113 114commit-msg 115~~~~~~~~~~ 116 117This hook is invoked by 'git commit', and can be bypassed 118with `--no-verify` option. It takes a single parameter, the 119name of the file that holds the proposed commit log message. 120Exiting with non-zero status causes the 'git commit' to 121abort. 122 123The hook is allowed to edit the message file in place, and can 124be used to normalize the message into some project standard 125format (if the project has one). It can also be used to refuse 126the commit after inspecting the message file. 127 128The default 'commit-msg' hook, when enabled, detects duplicate 129"Signed-off-by" lines, and aborts the commit if one is found. 130 131post-commit 132~~~~~~~~~~~ 133 134This hook is invoked by 'git commit'. It takes no 135parameter, and is invoked after a commit is made. 136 137This hook is meant primarily for notification, and cannot affect 138the outcome of 'git commit'. 139 140pre-rebase 141~~~~~~~~~~ 142 143This hook is called by 'git rebase' and can be used to prevent a 144branch from getting rebased. The hook may be called with one or 145two parameters. The first parameter is the upstream from which 146the series was forked. The second parameter is the branch being 147rebased, and is not set when rebasing the current branch. 148 149post-checkout 150~~~~~~~~~~~~~ 151 152This hook is invoked when a 'git checkout' is run after having updated the 153worktree. The hook is given three parameters: the ref of the previous HEAD, 154the ref of the new HEAD (which may or may not have changed), and a flag 155indicating whether the checkout was a branch checkout (changing branches, 156flag=1) or a file checkout (retrieving a file from the index, flag=0). 157This hook cannot affect the outcome of 'git checkout'. 158 159It is also run after 'git clone', unless the --no-checkout (-n) option is 160used. The first parameter given to the hook is the null-ref, the second the 161ref of the new HEAD and the flag is always 1. 162 163This hook can be used to perform repository validity checks, auto-display 164differences from the previous HEAD if different, or set working dir metadata 165properties. 166 167post-merge 168~~~~~~~~~~ 169 170This hook is invoked by 'git merge', which happens when a 'git pull' 171is done on a local repository. The hook takes a single parameter, a status 172flag specifying whether or not the merge being done was a squash merge. 173This hook cannot affect the outcome of 'git merge' and is not executed, 174if the merge failed due to conflicts. 175 176This hook can be used in conjunction with a corresponding pre-commit hook to 177save and restore any form of metadata associated with the working tree 178(e.g.: permissions/ownership, ACLS, etc). See contrib/hooks/setgitperms.perl 179for an example of how to do this. 180 181pre-push 182~~~~~~~~ 183 184This hook is called by 'git push' and can be used to prevent a push from taking 185place. The hook is called with two parameters which provide the name and 186location of the destination remote, if a named remote is not being used both 187values will be the same. 188 189Information about what is to be pushed is provided on the hook's standard 190input with lines of the form: 191 192 <local ref> SP <local sha1> SP <remote ref> SP <remote sha1> LF 193 194For instance, if the command +git push origin master:foreign+ were run the 195hook would receive a line like the following: 196 197 refs/heads/master 67890 refs/heads/foreign 12345 198 199although the full, 40-character SHA-1s would be supplied. If the foreign ref 200does not yet exist the `<remote SHA-1>` will be 40 `0`. If a ref is to be 201deleted, the `<local ref>` will be supplied as `(delete)` and the `<local 202SHA-1>` will be 40 `0`. If the local commit was specified by something other 203than a name which could be expanded (such as `HEAD~`, or a SHA-1) it will be 204supplied as it was originally given. 205 206If this hook exits with a non-zero status, 'git push' will abort without 207pushing anything. Information about why the push is rejected may be sent 208to the user by writing to standard error. 209 210[[pre-receive]] 211pre-receive 212~~~~~~~~~~~ 213 214This hook is invoked by 'git-receive-pack' on the remote repository, 215which happens when a 'git push' is done on a local repository. 216Just before starting to update refs on the remote repository, the 217pre-receive hook is invoked. Its exit status determines the success 218or failure of the update. 219 220This hook executes once for the receive operation. It takes no 221arguments, but for each ref to be updated it receives on standard 222input a line of the format: 223 224 <old-value> SP <new-value> SP <ref-name> LF 225 226where `<old-value>` is the old object name stored in the ref, 227`<new-value>` is the new object name to be stored in the ref and 228`<ref-name>` is the full name of the ref. 229When creating a new ref, `<old-value>` is 40 `0`. 230 231If the hook exits with non-zero status, none of the refs will be 232updated. If the hook exits with zero, updating of individual refs can 233still be prevented by the <<update,'update'>> hook. 234 235Both standard output and standard error output are forwarded to 236'git send-pack' on the other end, so you can simply `echo` messages 237for the user. 238 239[[update]] 240update 241~~~~~~ 242 243This hook is invoked by 'git-receive-pack' on the remote repository, 244which happens when a 'git push' is done on a local repository. 245Just before updating the ref on the remote repository, the update hook 246is invoked. Its exit status determines the success or failure of 247the ref update. 248 249The hook executes once for each ref to be updated, and takes 250three parameters: 251 252 - the name of the ref being updated, 253 - the old object name stored in the ref, 254 - and the new object name to be stored in the ref. 255 256A zero exit from the update hook allows the ref to be updated. 257Exiting with a non-zero status prevents 'git-receive-pack' 258from updating that ref. 259 260This hook can be used to prevent 'forced' update on certain refs by 261making sure that the object name is a commit object that is a 262descendant of the commit object named by the old object name. 263That is, to enforce a "fast-forward only" policy. 264 265It could also be used to log the old..new status. However, it 266does not know the entire set of branches, so it would end up 267firing one e-mail per ref when used naively, though. The 268<<post-receive,'post-receive'>> hook is more suited to that. 269 270Another use suggested on the mailing list is to use this hook to 271implement access control which is finer grained than the one 272based on filesystem group. 273 274Both standard output and standard error output are forwarded to 275'git send-pack' on the other end, so you can simply `echo` messages 276for the user. 277 278The default 'update' hook, when enabled--and with 279`hooks.allowunannotated` config option unset or set to false--prevents 280unannotated tags to be pushed. 281 282[[post-receive]] 283post-receive 284~~~~~~~~~~~~ 285 286This hook is invoked by 'git-receive-pack' on the remote repository, 287which happens when a 'git push' is done on a local repository. 288It executes on the remote repository once after all the refs have 289been updated. 290 291This hook executes once for the receive operation. It takes no 292arguments, but gets the same information as the 293<<pre-receive,'pre-receive'>> 294hook does on its standard input. 295 296This hook does not affect the outcome of 'git-receive-pack', as it 297is called after the real work is done. 298 299This supersedes the <<post-update,'post-update'>> hook in that it gets 300both old and new values of all the refs in addition to their 301names. 302 303Both standard output and standard error output are forwarded to 304'git send-pack' on the other end, so you can simply `echo` messages 305for the user. 306 307The default 'post-receive' hook is empty, but there is 308a sample script `post-receive-email` provided in the `contrib/hooks` 309directory in Git distribution, which implements sending commit 310emails. 311 312[[post-update]] 313post-update 314~~~~~~~~~~~ 315 316This hook is invoked by 'git-receive-pack' on the remote repository, 317which happens when a 'git push' is done on a local repository. 318It executes on the remote repository once after all the refs have 319been updated. 320 321It takes a variable number of parameters, each of which is the 322name of ref that was actually updated. 323 324This hook is meant primarily for notification, and cannot affect 325the outcome of 'git-receive-pack'. 326 327The 'post-update' hook can tell what are the heads that were pushed, 328but it does not know what their original and updated values are, 329so it is a poor place to do log old..new. The 330<<post-receive,'post-receive'>> hook does get both original and 331updated values of the refs. You might consider it instead if you need 332them. 333 334When enabled, the default 'post-update' hook runs 335'git update-server-info' to keep the information used by dumb 336transports (e.g., HTTP) up-to-date. If you are publishing 337a Git repository that is accessible via HTTP, you should 338probably enable this hook. 339 340Both standard output and standard error output are forwarded to 341'git send-pack' on the other end, so you can simply `echo` messages 342for the user. 343 344pre-auto-gc 345~~~~~~~~~~~ 346 347This hook is invoked by 'git gc --auto'. It takes no parameter, and 348exiting with non-zero status from this script causes the 'git gc --auto' 349to abort. 350 351post-rewrite 352~~~~~~~~~~~~ 353 354This hook is invoked by commands that rewrite commits (`git commit 355--amend`, 'git-rebase'; currently 'git-filter-branch' does 'not' call 356it!). Its first argument denotes the command it was invoked by: 357currently one of `amend` or `rebase`. Further command-dependent 358arguments may be passed in the future. 359 360The hook receives a list of the rewritten commits on stdin, in the 361format 362 363 <old-sha1> SP <new-sha1> [ SP <extra-info> ] LF 364 365The 'extra-info' is again command-dependent. If it is empty, the 366preceding SP is also omitted. Currently, no commands pass any 367'extra-info'. 368 369The hook always runs after the automatic note copying (see 370"notes.rewrite.<command>" in linkgit:git-config.txt[1]) has happened, and 371thus has access to these notes. 372 373The following command-specific comments apply: 374 375rebase:: 376 For the 'squash' and 'fixup' operation, all commits that were 377 squashed are listed as being rewritten to the squashed commit. 378 This means that there will be several lines sharing the same 379 'new-sha1'. 380+ 381The commits are guaranteed to be listed in the order that they were 382processed by rebase. 383 384 385GIT 386--- 387Part of the linkgit:git[1] suite