Documentation / git-push.txton commit doc hash-function-transition: clarify how older gits die on NewHash (45fa195)
   1git-push(1)
   2===========
   3
   4NAME
   5----
   6git-push - Update remote refs along with associated objects
   7
   8
   9SYNOPSIS
  10--------
  11[verse]
  12'git push' [--all | --mirror | --tags] [--follow-tags] [--atomic] [-n | --dry-run] [--receive-pack=<git-receive-pack>]
  13           [--repo=<repository>] [-f | --force] [-d | --delete] [--prune] [-v | --verbose]
  14           [-u | --set-upstream] [--push-option=<string>]
  15           [--[no-]signed|--signed=(true|false|if-asked)]
  16           [--force-with-lease[=<refname>[:<expect>]]]
  17           [--no-verify] [<repository> [<refspec>...]]
  18
  19DESCRIPTION
  20-----------
  21
  22Updates remote refs using local refs, while sending objects
  23necessary to complete the given refs.
  24
  25You can make interesting things happen to a repository
  26every time you push into it, by setting up 'hooks' there.  See
  27documentation for linkgit:git-receive-pack[1].
  28
  29When the command line does not specify where to push with the
  30`<repository>` argument, `branch.*.remote` configuration for the
  31current branch is consulted to determine where to push.  If the
  32configuration is missing, it defaults to 'origin'.
  33
  34When the command line does not specify what to push with `<refspec>...`
  35arguments or `--all`, `--mirror`, `--tags` options, the command finds
  36the default `<refspec>` by consulting `remote.*.push` configuration,
  37and if it is not found, honors `push.default` configuration to decide
  38what to push (See linkgit:git-config[1] for the meaning of `push.default`).
  39
  40When neither the command-line nor the configuration specify what to
  41push, the default behavior is used, which corresponds to the `simple`
  42value for `push.default`: the current branch is pushed to the
  43corresponding upstream branch, but as a safety measure, the push is
  44aborted if the upstream branch does not have the same name as the
  45local one.
  46
  47
  48OPTIONS[[OPTIONS]]
  49------------------
  50<repository>::
  51        The "remote" repository that is destination of a push
  52        operation.  This parameter can be either a URL
  53        (see the section <<URLS,GIT URLS>> below) or the name
  54        of a remote (see the section <<REMOTES,REMOTES>> below).
  55
  56<refspec>...::
  57        Specify what destination ref to update with what source object.
  58        The format of a <refspec> parameter is an optional plus
  59        `+`, followed by the source object <src>, followed
  60        by a colon `:`, followed by the destination ref <dst>.
  61+
  62The <src> is often the name of the branch you would want to push, but
  63it can be any arbitrary "SHA-1 expression", such as `master~4` or
  64`HEAD` (see linkgit:gitrevisions[7]).
  65+
  66The <dst> tells which ref on the remote side is updated with this
  67push. Arbitrary expressions cannot be used here, an actual ref must
  68be named.
  69If `git push [<repository>]` without any `<refspec>` argument is set to
  70update some ref at the destination with `<src>` with
  71`remote.<repository>.push` configuration variable, `:<dst>` part can
  72be omitted--such a push will update a ref that `<src>` normally updates
  73without any `<refspec>` on the command line.  Otherwise, missing
  74`:<dst>` means to update the same ref as the `<src>`.
  75+
  76The object referenced by <src> is used to update the <dst> reference
  77on the remote side.  By default this is only allowed if <dst> is not
  78a tag (annotated or lightweight), and then only if it can fast-forward
  79<dst>.  By having the optional leading `+`, you can tell Git to update
  80the <dst> ref even if it is not allowed by default (e.g., it is not a
  81fast-forward.)  This does *not* attempt to merge <src> into <dst>.  See
  82EXAMPLES below for details.
  83+
  84`tag <tag>` means the same as `refs/tags/<tag>:refs/tags/<tag>`.
  85+
  86Pushing an empty <src> allows you to delete the <dst> ref from
  87the remote repository.
  88+
  89The special refspec `:` (or `+:` to allow non-fast-forward updates)
  90directs Git to push "matching" branches: for every branch that exists on
  91the local side, the remote side is updated if a branch of the same name
  92already exists on the remote side.
  93
  94--all::
  95        Push all branches (i.e. refs under `refs/heads/`); cannot be
  96        used with other <refspec>.
  97
  98--prune::
  99        Remove remote branches that don't have a local counterpart. For example
 100        a remote branch `tmp` will be removed if a local branch with the same
 101        name doesn't exist any more. This also respects refspecs, e.g.
 102        `git push --prune remote refs/heads/*:refs/tmp/*` would
 103        make sure that remote `refs/tmp/foo` will be removed if `refs/heads/foo`
 104        doesn't exist.
 105
 106--mirror::
 107        Instead of naming each ref to push, specifies that all
 108        refs under `refs/` (which includes but is not
 109        limited to `refs/heads/`, `refs/remotes/`, and `refs/tags/`)
 110        be mirrored to the remote repository.  Newly created local
 111        refs will be pushed to the remote end, locally updated refs
 112        will be force updated on the remote end, and deleted refs
 113        will be removed from the remote end.  This is the default
 114        if the configuration option `remote.<remote>.mirror` is
 115        set.
 116
 117-n::
 118--dry-run::
 119        Do everything except actually send the updates.
 120
 121--porcelain::
 122        Produce machine-readable output.  The output status line for each ref
 123        will be tab-separated and sent to stdout instead of stderr.  The full
 124        symbolic names of the refs will be given.
 125
 126--delete::
 127        All listed refs are deleted from the remote repository. This is
 128        the same as prefixing all refs with a colon.
 129
 130--tags::
 131        All refs under `refs/tags` are pushed, in
 132        addition to refspecs explicitly listed on the command
 133        line.
 134
 135--follow-tags::
 136        Push all the refs that would be pushed without this option,
 137        and also push annotated tags in `refs/tags` that are missing
 138        from the remote but are pointing at commit-ish that are
 139        reachable from the refs being pushed.  This can also be specified
 140        with configuration variable `push.followTags`.  For more
 141        information, see `push.followTags` in linkgit:git-config[1].
 142
 143--[no-]signed::
 144--signed=(true|false|if-asked)::
 145        GPG-sign the push request to update refs on the receiving
 146        side, to allow it to be checked by the hooks and/or be
 147        logged.  If `false` or `--no-signed`, no signing will be
 148        attempted.  If `true` or `--signed`, the push will fail if the
 149        server does not support signed pushes.  If set to `if-asked`,
 150        sign if and only if the server supports signed pushes.  The push
 151        will also fail if the actual call to `gpg --sign` fails.  See
 152        linkgit:git-receive-pack[1] for the details on the receiving end.
 153
 154--[no-]atomic::
 155        Use an atomic transaction on the remote side if available.
 156        Either all refs are updated, or on error, no refs are updated.
 157        If the server does not support atomic pushes the push will fail.
 158
 159-o <option>::
 160--push-option=<option>::
 161        Transmit the given string to the server, which passes them to
 162        the pre-receive as well as the post-receive hook. The given string
 163        must not contain a NUL or LF character.
 164        When multiple `--push-option=<option>` are given, they are
 165        all sent to the other side in the order listed on the
 166        command line.
 167        When no `--push-option=<option>` is given from the command
 168        line, the values of configuration variable `push.pushOption`
 169        are used instead.
 170
 171--receive-pack=<git-receive-pack>::
 172--exec=<git-receive-pack>::
 173        Path to the 'git-receive-pack' program on the remote
 174        end.  Sometimes useful when pushing to a remote
 175        repository over ssh, and you do not have the program in
 176        a directory on the default $PATH.
 177
 178--[no-]force-with-lease::
 179--force-with-lease=<refname>::
 180--force-with-lease=<refname>:<expect>::
 181        Usually, "git push" refuses to update a remote ref that is
 182        not an ancestor of the local ref used to overwrite it.
 183+
 184This option overrides this restriction if the current value of the
 185remote ref is the expected value.  "git push" fails otherwise.
 186+
 187Imagine that you have to rebase what you have already published.
 188You will have to bypass the "must fast-forward" rule in order to
 189replace the history you originally published with the rebased history.
 190If somebody else built on top of your original history while you are
 191rebasing, the tip of the branch at the remote may advance with her
 192commit, and blindly pushing with `--force` will lose her work.
 193+
 194This option allows you to say that you expect the history you are
 195updating is what you rebased and want to replace. If the remote ref
 196still points at the commit you specified, you can be sure that no
 197other people did anything to the ref. It is like taking a "lease" on
 198the ref without explicitly locking it, and the remote ref is updated
 199only if the "lease" is still valid.
 200+
 201`--force-with-lease` alone, without specifying the details, will protect
 202all remote refs that are going to be updated by requiring their
 203current value to be the same as the remote-tracking branch we have
 204for them.
 205+
 206`--force-with-lease=<refname>`, without specifying the expected value, will
 207protect the named ref (alone), if it is going to be updated, by
 208requiring its current value to be the same as the remote-tracking
 209branch we have for it.
 210+
 211`--force-with-lease=<refname>:<expect>` will protect the named ref (alone),
 212if it is going to be updated, by requiring its current value to be
 213the same as the specified value `<expect>` (which is allowed to be
 214different from the remote-tracking branch we have for the refname,
 215or we do not even have to have such a remote-tracking branch when
 216this form is used).  If `<expect>` is the empty string, then the named ref
 217must not already exist.
 218+
 219Note that all forms other than `--force-with-lease=<refname>:<expect>`
 220that specifies the expected current value of the ref explicitly are
 221still experimental and their semantics may change as we gain experience
 222with this feature.
 223+
 224"--no-force-with-lease" will cancel all the previous --force-with-lease on the
 225command line.
 226+
 227A general note on safety: supplying this option without an expected
 228value, i.e. as `--force-with-lease` or `--force-with-lease=<refname>`
 229interacts very badly with anything that implicitly runs `git fetch` on
 230the remote to be pushed to in the background, e.g. `git fetch origin`
 231on your repository in a cronjob.
 232+
 233The protection it offers over `--force` is ensuring that subsequent
 234changes your work wasn't based on aren't clobbered, but this is
 235trivially defeated if some background process is updating refs in the
 236background. We don't have anything except the remote tracking info to
 237go by as a heuristic for refs you're expected to have seen & are
 238willing to clobber.
 239+
 240If your editor or some other system is running `git fetch` in the
 241background for you a way to mitigate this is to simply set up another
 242remote:
 243+
 244        git remote add origin-push $(git config remote.origin.url)
 245        git fetch origin-push
 246+
 247Now when the background process runs `git fetch origin` the references
 248on `origin-push` won't be updated, and thus commands like:
 249+
 250        git push --force-with-lease origin-push
 251+
 252Will fail unless you manually run `git fetch origin-push`. This method
 253is of course entirely defeated by something that runs `git fetch
 254--all`, in that case you'd need to either disable it or do something
 255more tedious like:
 256+
 257        git fetch              # update 'master' from remote
 258        git tag base master    # mark our base point
 259        git rebase -i master   # rewrite some commits
 260        git push --force-with-lease=master:base master:master
 261+
 262I.e. create a `base` tag for versions of the upstream code that you've
 263seen and are willing to overwrite, then rewrite history, and finally
 264force push changes to `master` if the remote version is still at
 265`base`, regardless of what your local `remotes/origin/master` has been
 266updated to in the background.
 267
 268-f::
 269--force::
 270        Usually, the command refuses to update a remote ref that is
 271        not an ancestor of the local ref used to overwrite it.
 272        Also, when `--force-with-lease` option is used, the command refuses
 273        to update a remote ref whose current value does not match
 274        what is expected.
 275+
 276This flag disables these checks, and can cause the remote repository
 277to lose commits; use it with care.
 278+
 279Note that `--force` applies to all the refs that are pushed, hence
 280using it with `push.default` set to `matching` or with multiple push
 281destinations configured with `remote.*.push` may overwrite refs
 282other than the current branch (including local refs that are
 283strictly behind their remote counterpart).  To force a push to only
 284one branch, use a `+` in front of the refspec to push (e.g `git push
 285origin +master` to force a push to the `master` branch). See the
 286`<refspec>...` section above for details.
 287
 288--repo=<repository>::
 289        This option is equivalent to the <repository> argument. If both
 290        are specified, the command-line argument takes precedence.
 291
 292-u::
 293--set-upstream::
 294        For every branch that is up to date or successfully pushed, add
 295        upstream (tracking) reference, used by argument-less
 296        linkgit:git-pull[1] and other commands. For more information,
 297        see `branch.<name>.merge` in linkgit:git-config[1].
 298
 299--[no-]thin::
 300        These options are passed to linkgit:git-send-pack[1]. A thin transfer
 301        significantly reduces the amount of sent data when the sender and
 302        receiver share many of the same objects in common. The default is
 303        \--thin.
 304
 305-q::
 306--quiet::
 307        Suppress all output, including the listing of updated refs,
 308        unless an error occurs. Progress is not reported to the standard
 309        error stream.
 310
 311-v::
 312--verbose::
 313        Run verbosely.
 314
 315--progress::
 316        Progress status is reported on the standard error stream
 317        by default when it is attached to a terminal, unless -q
 318        is specified. This flag forces progress status even if the
 319        standard error stream is not directed to a terminal.
 320
 321--no-recurse-submodules::
 322--recurse-submodules=check|on-demand|only|no::
 323        May be used to make sure all submodule commits used by the
 324        revisions to be pushed are available on a remote-tracking branch.
 325        If 'check' is used Git will verify that all submodule commits that
 326        changed in the revisions to be pushed are available on at least one
 327        remote of the submodule. If any commits are missing the push will
 328        be aborted and exit with non-zero status. If 'on-demand' is used
 329        all submodules that changed in the revisions to be pushed will be
 330        pushed. If on-demand was not able to push all necessary revisions it will
 331        also be aborted and exit with non-zero status. If 'only' is used all
 332        submodules will be recursively pushed while the superproject is left
 333        unpushed. A value of 'no' or using `--no-recurse-submodules` can be used
 334        to override the push.recurseSubmodules configuration variable when no
 335        submodule recursion is required.
 336
 337--[no-]verify::
 338        Toggle the pre-push hook (see linkgit:githooks[5]).  The
 339        default is --verify, giving the hook a chance to prevent the
 340        push.  With --no-verify, the hook is bypassed completely.
 341
 342-4::
 343--ipv4::
 344        Use IPv4 addresses only, ignoring IPv6 addresses.
 345
 346-6::
 347--ipv6::
 348        Use IPv6 addresses only, ignoring IPv4 addresses.
 349
 350include::urls-remotes.txt[]
 351
 352OUTPUT
 353------
 354
 355The output of "git push" depends on the transport method used; this
 356section describes the output when pushing over the Git protocol (either
 357locally or via ssh).
 358
 359The status of the push is output in tabular form, with each line
 360representing the status of a single ref. Each line is of the form:
 361
 362-------------------------------
 363 <flag> <summary> <from> -> <to> (<reason>)
 364-------------------------------
 365
 366If --porcelain is used, then each line of the output is of the form:
 367
 368-------------------------------
 369 <flag> \t <from>:<to> \t <summary> (<reason>)
 370-------------------------------
 371
 372The status of up-to-date refs is shown only if --porcelain or --verbose
 373option is used.
 374
 375flag::
 376        A single character indicating the status of the ref:
 377(space);; for a successfully pushed fast-forward;
 378`+`;; for a successful forced update;
 379`-`;; for a successfully deleted ref;
 380`*`;; for a successfully pushed new ref;
 381`!`;; for a ref that was rejected or failed to push; and
 382`=`;; for a ref that was up to date and did not need pushing.
 383
 384summary::
 385        For a successfully pushed ref, the summary shows the old and new
 386        values of the ref in a form suitable for using as an argument to
 387        `git log` (this is `<old>..<new>` in most cases, and
 388        `<old>...<new>` for forced non-fast-forward updates).
 389+
 390For a failed update, more details are given:
 391+
 392--
 393rejected::
 394        Git did not try to send the ref at all, typically because it
 395        is not a fast-forward and you did not force the update.
 396
 397remote rejected::
 398        The remote end refused the update.  Usually caused by a hook
 399        on the remote side, or because the remote repository has one
 400        of the following safety options in effect:
 401        `receive.denyCurrentBranch` (for pushes to the checked out
 402        branch), `receive.denyNonFastForwards` (for forced
 403        non-fast-forward updates), `receive.denyDeletes` or
 404        `receive.denyDeleteCurrent`.  See linkgit:git-config[1].
 405
 406remote failure::
 407        The remote end did not report the successful update of the ref,
 408        perhaps because of a temporary error on the remote side, a
 409        break in the network connection, or other transient error.
 410--
 411
 412from::
 413        The name of the local ref being pushed, minus its
 414        `refs/<type>/` prefix. In the case of deletion, the
 415        name of the local ref is omitted.
 416
 417to::
 418        The name of the remote ref being updated, minus its
 419        `refs/<type>/` prefix.
 420
 421reason::
 422        A human-readable explanation. In the case of successfully pushed
 423        refs, no explanation is needed. For a failed ref, the reason for
 424        failure is described.
 425
 426Note about fast-forwards
 427------------------------
 428
 429When an update changes a branch (or more in general, a ref) that used to
 430point at commit A to point at another commit B, it is called a
 431fast-forward update if and only if B is a descendant of A.
 432
 433In a fast-forward update from A to B, the set of commits that the original
 434commit A built on top of is a subset of the commits the new commit B
 435builds on top of.  Hence, it does not lose any history.
 436
 437In contrast, a non-fast-forward update will lose history.  For example,
 438suppose you and somebody else started at the same commit X, and you built
 439a history leading to commit B while the other person built a history
 440leading to commit A.  The history looks like this:
 441
 442----------------
 443
 444      B
 445     /
 446 ---X---A
 447
 448----------------
 449
 450Further suppose that the other person already pushed changes leading to A
 451back to the original repository from which you two obtained the original
 452commit X.
 453
 454The push done by the other person updated the branch that used to point at
 455commit X to point at commit A.  It is a fast-forward.
 456
 457But if you try to push, you will attempt to update the branch (that
 458now points at A) with commit B.  This does _not_ fast-forward.  If you did
 459so, the changes introduced by commit A will be lost, because everybody
 460will now start building on top of B.
 461
 462The command by default does not allow an update that is not a fast-forward
 463to prevent such loss of history.
 464
 465If you do not want to lose your work (history from X to B) or the work by
 466the other person (history from X to A), you would need to first fetch the
 467history from the repository, create a history that contains changes done
 468by both parties, and push the result back.
 469
 470You can perform "git pull", resolve potential conflicts, and "git push"
 471the result.  A "git pull" will create a merge commit C between commits A
 472and B.
 473
 474----------------
 475
 476      B---C
 477     /   /
 478 ---X---A
 479
 480----------------
 481
 482Updating A with the resulting merge commit will fast-forward and your
 483push will be accepted.
 484
 485Alternatively, you can rebase your change between X and B on top of A,
 486with "git pull --rebase", and push the result back.  The rebase will
 487create a new commit D that builds the change between X and B on top of
 488A.
 489
 490----------------
 491
 492      B   D
 493     /   /
 494 ---X---A
 495
 496----------------
 497
 498Again, updating A with this commit will fast-forward and your push will be
 499accepted.
 500
 501There is another common situation where you may encounter non-fast-forward
 502rejection when you try to push, and it is possible even when you are
 503pushing into a repository nobody else pushes into. After you push commit
 504A yourself (in the first picture in this section), replace it with "git
 505commit --amend" to produce commit B, and you try to push it out, because
 506forgot that you have pushed A out already. In such a case, and only if
 507you are certain that nobody in the meantime fetched your earlier commit A
 508(and started building on top of it), you can run "git push --force" to
 509overwrite it. In other words, "git push --force" is a method reserved for
 510a case where you do mean to lose history.
 511
 512
 513Examples
 514--------
 515
 516`git push`::
 517        Works like `git push <remote>`, where <remote> is the
 518        current branch's remote (or `origin`, if no remote is
 519        configured for the current branch).
 520
 521`git push origin`::
 522        Without additional configuration, pushes the current branch to
 523        the configured upstream (`remote.origin.merge` configuration
 524        variable) if it has the same name as the current branch, and
 525        errors out without pushing otherwise.
 526+
 527The default behavior of this command when no <refspec> is given can be
 528configured by setting the `push` option of the remote, or the `push.default`
 529configuration variable.
 530+
 531For example, to default to pushing only the current branch to `origin`
 532use `git config remote.origin.push HEAD`.  Any valid <refspec> (like
 533the ones in the examples below) can be configured as the default for
 534`git push origin`.
 535
 536`git push origin :`::
 537        Push "matching" branches to `origin`. See
 538        <refspec> in the <<OPTIONS,OPTIONS>> section above for a
 539        description of "matching" branches.
 540
 541`git push origin master`::
 542        Find a ref that matches `master` in the source repository
 543        (most likely, it would find `refs/heads/master`), and update
 544        the same ref (e.g. `refs/heads/master`) in `origin` repository
 545        with it.  If `master` did not exist remotely, it would be
 546        created.
 547
 548`git push origin HEAD`::
 549        A handy way to push the current branch to the same name on the
 550        remote.
 551
 552`git push mothership master:satellite/master dev:satellite/dev`::
 553        Use the source ref that matches `master` (e.g. `refs/heads/master`)
 554        to update the ref that matches `satellite/master` (most probably
 555        `refs/remotes/satellite/master`) in the `mothership` repository;
 556        do the same for `dev` and `satellite/dev`.
 557+
 558This is to emulate `git fetch` run on the `mothership` using `git
 559push` that is run in the opposite direction in order to integrate
 560the work done on `satellite`, and is often necessary when you can
 561only make connection in one way (i.e. satellite can ssh into
 562mothership but mothership cannot initiate connection to satellite
 563because the latter is behind a firewall or does not run sshd).
 564+
 565After running this `git push` on the `satellite` machine, you would
 566ssh into the `mothership` and run `git merge` there to complete the
 567emulation of `git pull` that were run on `mothership` to pull changes
 568made on `satellite`.
 569
 570`git push origin HEAD:master`::
 571        Push the current branch to the remote ref matching `master` in the
 572        `origin` repository. This form is convenient to push the current
 573        branch without thinking about its local name.
 574
 575`git push origin master:refs/heads/experimental`::
 576        Create the branch `experimental` in the `origin` repository
 577        by copying the current `master` branch.  This form is only
 578        needed to create a new branch or tag in the remote repository when
 579        the local name and the remote name are different; otherwise,
 580        the ref name on its own will work.
 581
 582`git push origin :experimental`::
 583        Find a ref that matches `experimental` in the `origin` repository
 584        (e.g. `refs/heads/experimental`), and delete it.
 585
 586`git push origin +dev:master`::
 587        Update the origin repository's master branch with the dev branch,
 588        allowing non-fast-forward updates.  *This can leave unreferenced
 589        commits dangling in the origin repository.*  Consider the
 590        following situation, where a fast-forward is not possible:
 591+
 592----
 593            o---o---o---A---B  origin/master
 594                     \
 595                      X---Y---Z  dev
 596----
 597+
 598The above command would change the origin repository to
 599+
 600----
 601                      A---B  (unnamed branch)
 602                     /
 603            o---o---o---X---Y---Z  master
 604----
 605+
 606Commits A and B would no longer belong to a branch with a symbolic name,
 607and so would be unreachable.  As such, these commits would be removed by
 608a `git gc` command on the origin repository.
 609
 610include::transfer-data-leaks.txt[]
 611
 612GIT
 613---
 614Part of the linkgit:git[1] suite