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GIT-PUSH(1) Git Manual GIT-PUSH(1)
NNAAMMEE
git-push - Update remote refs along with associated objects
SSYYNNOOPPSSIISS
_g_i_t _p_u_s_h [--all | --mirror | --tags] [--follow-tags] [--atomic] [-n | --dry-run] [--receive-pack=<git-receive-pack>]
[--repo=<repository>] [-f | --force] [-d | --delete] [--prune] [-v | --verbose]
[-u | --set-upstream] [--push-option=<string>]
[--[no-]signed|--signed=(true|false|if-asked)]
[--force-with-lease[=<refname>[:<expect>]]]
[--no-verify] [<repository> [<refspec>...]]
DDEESSCCRRIIPPTTIIOONN
Updates remote refs using local refs, while sending objects necessary to complete the given refs.
You can make interesting things happen to a repository every time you push into it, by setting up _h_o_o_k_s there. See documentation for
ggiitt--rreecceeiivvee--ppaacckk(1).
When the command line does not specify where to push with the <<rreeppoossiittoorryy>> argument, bbrraanncchh..**..rreemmoottee configuration for the current
branch is consulted to determine where to push. If the configuration is missing, it defaults to _o_r_i_g_i_n.
When the command line does not specify what to push with <<rreeffssppeecc>>...... arguments or ----aallll, ----mmiirrrroorr, ----ttaaggss options, the command finds
the default <<rreeffssppeecc>> by consulting rreemmoottee..**..ppuusshh configuration, and if it is not found, honors ppuusshh..ddeeffaauulltt configuration to decide
what to push (See ggiitt--ccoonnffiigg(1) for the meaning of ppuusshh..ddeeffaauulltt).
When neither the command-line nor the configuration specify what to push, the default behavior is used, which corresponds to the
ssiimmppllee value for ppuusshh..ddeeffaauulltt: the current branch is pushed to the corresponding upstream branch, but as a safety measure, the push
is aborted if the upstream branch does not have the same name as the local one.
OOPPTTIIOONNSS
<repository>
The "remote" repository that is destination of a push operation. This parameter can be either a URL (see the section GIT URLS
below) or the name of a remote (see the section REMOTES below).
<refspec>...
Specify what destination ref to update with what source object. The format of a <refspec> parameter is an optional plus ++,
followed by the source object <src>, followed by a colon ::, followed by the destination ref <dst>.
The <src> is often the name of the branch you would want to push, but it can be any arbitrary "SHA-1 expression", such as
mmaasstteerr~~44 or HHEEAADD (see ggiittrreevviissiioonnss(7)).
The <dst> tells which ref on the remote side is updated with this push. Arbitrary expressions cannot be used here, an actual ref
must be named. If ggiitt ppuusshh [[<<rreeppoossiittoorryy>>]] without any <<rreeffssppeecc>> argument is set to update some ref at the destination with <<ssrrcc>>
with rreemmoottee..<<rreeppoossiittoorryy>>..ppuusshh configuration variable, ::<<ddsstt>> part can be omitted—such a push will update a ref that <<ssrrcc>>
normally updates without any <<rreeffssppeecc>> on the command line. Otherwise, missing ::<<ddsstt>> means to update the same ref as the <<ssrrcc>>.
The object referenced by <src> is used to update the <dst> reference on the remote side. By default this is only allowed if <dst>
is not a tag (annotated or lightweight), and then only if it can fast-forward <dst>. By having the optional leading ++, you can
tell Git to update the <dst> ref even if it is not allowed by default (e.g., it is not a fast-forward.) This does nnoott attempt to
merge <src> into <dst>. See EXAMPLES below for details.
ttaagg <<ttaagg>> means the same as rreeffss//ttaaggss//<<ttaagg>>::rreeffss//ttaaggss//<<ttaagg>>.
Pushing an empty <src> allows you to delete the <dst> ref from the remote repository.
The special refspec :: (or ++:: to allow non-fast-forward updates) directs Git to push "matching" branches: for every branch that
exists on the local side, the remote side is updated if a branch of the same name already exists on the remote side.
--all
Push all branches (i.e. refs under rreeffss//hheeaaddss//); cannot be used with other <refspec>.
--prune
Remove remote branches that don’t have a local counterpart. For example a remote branch ttmmpp will be removed if a local branch
with the same name doesn’t exist any more. This also respects refspecs, e.g. ggiitt ppuusshh ----pprruunnee rreemmoottee rreeffss//hheeaaddss//**::rreeffss//ttmmpp//**
would make sure that remote rreeffss//ttmmpp//ffoooo will be removed if rreeffss//hheeaaddss//ffoooo doesn’t exist.
--mirror
Instead of naming each ref to push, specifies that all refs under rreeffss// (which includes but is not limited to rreeffss//hheeaaddss//,
rreeffss//rreemmootteess//, and rreeffss//ttaaggss//) be mirrored to the remote repository. Newly created local refs will be pushed to the remote end,
locally updated refs will be force updated on the remote end, and deleted refs will be removed from the remote end. This is the
default if the configuration option rreemmoottee..<<rreemmoottee>>..mmiirrrroorr is set.
-n, --dry-run
Do everything except actually send the updates.
--porcelain
Produce machine-readable output. The output status line for each ref will be tab-separated and sent to stdout instead of stderr.
The full symbolic names of the refs will be given.
--delete
All listed refs are deleted from the remote repository. This is the same as prefixing all refs with a colon.
--tags
All refs under rreeffss//ttaaggss are pushed, in addition to refspecs explicitly listed on the command line.
--follow-tags
Push all the refs that would be pushed without this option, and also push annotated tags in rreeffss//ttaaggss that are missing from the
remote but are pointing at commit-ish that are reachable from the refs being pushed. This can also be specified with
configuration variable ppuusshh..ffoolllloowwTTaaggss. For more information, see ppuusshh..ffoolllloowwTTaaggss in ggiitt--ccoonnffiigg(1).
--[no-]signed, --signed=(true|false|if-asked)
GPG-sign the push request to update refs on the receiving side, to allow it to be checked by the hooks and/or be logged. If ffaallssee
or ----nnoo--ssiiggnneedd, no signing will be attempted. If ttrruuee or ----ssiiggnneedd, the push will fail if the server does not support signed
pushes. If set to iiff--aasskkeedd, sign if and only if the server supports signed pushes. The push will also fail if the actual call to
ggppgg ----ssiiggnn fails. See ggiitt--rreecceeiivvee--ppaacckk(1) for the details on the receiving end.
--[no-]atomic
Use an atomic transaction on the remote side if available. Either all refs are updated, or on error, no refs are updated. If the
server does not support atomic pushes the push will fail.
-o <option>, --push-option=<option>
Transmit the given string to the server, which passes them to the pre-receive as well as the post-receive hook. The given string
must not contain a NUL or LF character. When multiple ----ppuusshh--ooppttiioonn==<<ooppttiioonn>> are given, they are all sent to the other side in
the order listed on the command line. When no ----ppuusshh--ooppttiioonn==<<ooppttiioonn>> is given from the command line, the values of configuration
variable ppuusshh..ppuusshhOOppttiioonn are used instead.
--receive-pack=<git-receive-pack>, --exec=<git-receive-pack>
Path to the _g_i_t_-_r_e_c_e_i_v_e_-_p_a_c_k program on the remote end. Sometimes useful when pushing to a remote repository over ssh, and you do
not have the program in a directory on the default $PATH.
--[no-]force-with-lease, --force-with-lease=<refname>, --force-with-lease=<refname>:<expect>
Usually, "git push" refuses to update a remote ref that is not an ancestor of the local ref used to overwrite it.
This option overrides this restriction if the current value of the remote ref is the expected value. "git push" fails otherwise.
Imagine that you have to rebase what you have already published. You will have to bypass the "must fast-forward" rule in order to
replace the history you originally published with the rebased history. If somebody else built on top of your original history
while you are rebasing, the tip of the branch at the remote may advance with her commit, and blindly pushing with ----ffoorrccee will
lose her work.
This option allows you to say that you expect the history you are updating is what you rebased and want to replace. If the remote
ref still points at the commit you specified, you can be sure that no other people did anything to the ref. It is like taking a
"lease" on the ref without explicitly locking it, and the remote ref is updated only if the "lease" is still valid.
----ffoorrccee--wwiitthh--lleeaassee alone, without specifying the details, will protect all remote refs that are going to be updated by requiring
their current value to be the same as the remote-tracking branch we have for them.
----ffoorrccee--wwiitthh--lleeaassee==<<rreeffnnaammee>>, without specifying the expected value, will protect the named ref (alone), if it is going to be
updated, by requiring its current value to be the same as the remote-tracking branch we have for it.
----ffoorrccee--wwiitthh--lleeaassee==<<rreeffnnaammee>>::<<eexxppeecctt>> will protect the named ref (alone), if it is going to be updated, by requiring its current
value to be the same as the specified value <<eexxppeecctt>> (which is allowed to be different from the remote-tracking branch we have
for the refname, or we do not even have to have such a remote-tracking branch when this form is used). If <<eexxppeecctt>> is the empty
string, then the named ref must not already exist.
Note that all forms other than ----ffoorrccee--wwiitthh--lleeaassee==<<rreeffnnaammee>>::<<eexxppeecctt>> that specifies the expected current value of the ref
explicitly are still experimental and their semantics may change as we gain experience with this feature.
"--no-force-with-lease" will cancel all the previous --force-with-lease on the command line.
A general note on safety: supplying this option without an expected value, i.e. as ----ffoorrccee--wwiitthh--lleeaassee or
----ffoorrccee--wwiitthh--lleeaassee==<<rreeffnnaammee>> interacts very badly with anything that implicitly runs ggiitt ffeettcchh on the remote to be pushed to in
the background, e.g. ggiitt ffeettcchh oorriiggiinn on your repository in a cronjob.
The protection it offers over ----ffoorrccee is ensuring that subsequent changes your work wasn’t based on aren’t clobbered, but this is
trivially defeated if some background process is updating refs in the background. We don’t have anything except the remote
tracking info to go by as a heuristic for refs you’re expected to have seen & are willing to clobber.
If your editor or some other system is running ggiitt ffeettcchh in the background for you a way to mitigate this is to simply set up
another remote:
git remote add origin-push $(git config remote.origin.url)
git fetch origin-push
Now when the background process runs ggiitt ffeettcchh oorriiggiinn the references on oorriiggiinn--ppuusshh won’t be updated, and thus commands like:
git push --force-with-lease origin-push
Will fail unless you manually run ggiitt ffeettcchh oorriiggiinn--ppuusshh. This method is of course entirely defeated by something that runs ggiitt
ffeettcchh ----aallll, in that case you’d need to either disable it or do something more tedious like:
git fetch # update 'master' from remote
git tag base master # mark our base point
git rebase -i master # rewrite some commits
git push --force-with-lease=master:base master:master
I.e. create a bbaassee tag for versions of the upstream code that you’ve seen and are willing to overwrite, then rewrite history, and
finally force push changes to mmaasstteerr if the remote version is still at bbaassee, regardless of what your local rreemmootteess//oorriiggiinn//mmaasstteerr
has been updated to in the background.
-f, --force
Usually, the command refuses to update a remote ref that is not an ancestor of the local ref used to overwrite it. Also, when
----ffoorrccee--wwiitthh--lleeaassee option is used, the command refuses to update a remote ref whose current value does not match what is
expected.
This flag disables these checks, and can cause the remote repository to lose commits; use it with care.
Note that ----ffoorrccee applies to all the refs that are pushed, hence using it with ppuusshh..ddeeffaauulltt set to mmaattcchhiinngg or with multiple push
destinations configured with rreemmoottee..**..ppuusshh may overwrite refs other than the current branch (including local refs that are
strictly behind their remote counterpart). To force a push to only one branch, use a ++ in front of the refspec to push (e.g ggiitt
ppuusshh oorriiggiinn ++mmaasstteerr to force a push to the mmaasstteerr branch). See the <<rreeffssppeecc>>...... section above for details.
--repo=<repository>
This option is equivalent to the <repository> argument. If both are specified, the command-line argument takes precedence.
-u, --set-upstream
For every branch that is up to date or successfully pushed, add upstream (tracking) reference, used by argument-less ggiitt--ppuullll(1)
and other commands. For more information, see bbrraanncchh..<<nnaammee>>..mmeerrggee in ggiitt--ccoonnffiigg(1).
--[no-]thin
These options are passed to ggiitt--sseenndd--ppaacckk(1). A thin transfer significantly reduces the amount of sent data when the sender and
receiver share many of the same objects in common. The default is --thin.
-q, --quiet
Suppress all output, including the listing of updated refs, unless an error occurs. Progress is not reported to the standard
error stream.
-v, --verbose
Run verbosely.
--progress
Progress status is reported on the standard error stream by default when it is attached to a terminal, unless -q is specified.
This flag forces progress status even if the standard error stream is not directed to a terminal.
--no-recurse-submodules, --recurse-submodules=check|on-demand|only|no
May be used to make sure all submodule commits used by the revisions to be pushed are available on a remote-tracking branch. If
_c_h_e_c_k is used Git will verify that all submodule commits that changed in the revisions to be pushed are available on at least one
remote of the submodule. If any commits are missing the push will be aborted and exit with non-zero status. If _o_n_-_d_e_m_a_n_d is used
all submodules that changed in the revisions to be pushed will be pushed. If on-demand was not able to push all necessary
revisions it will also be aborted and exit with non-zero status. If _o_n_l_y is used all submodules will be recursively pushed while
the superproject is left unpushed. A value of _n_o or using ----nnoo--rreeccuurrssee--ssuubbmmoodduulleess can be used to override the
push.recurseSubmodules configuration variable when no submodule recursion is required.
--[no-]verify
Toggle the pre-push hook (see ggiitthhooookkss(5)). The default is --verify, giving the hook a chance to prevent the push. With
--no-verify, the hook is bypassed completely.
-4, --ipv4
Use IPv4 addresses only, ignoring IPv6 addresses.
-6, --ipv6
Use IPv6 addresses only, ignoring IPv4 addresses.
GGIITT UURRLLSS
In general, URLs contain information about the transport protocol, the address of the remote server, and the path to the repository.
Depending on the transport protocol, some of this information may be absent.
Git supports ssh, git, http, and https protocols (in addition, ftp, and ftps can be used for fetching, but this is inefficient and
deprecated; do not use it).
The native transport (i.e. git:// URL) does no authentication and should be used with caution on unsecured networks.
The following syntaxes may be used with them:
· ssh://[user@]host.xz[:port]/path/to/repo.git/
· git://host.xz[:port]/path/to/repo.git/
· http[s]://host.xz[:port]/path/to/repo.git/
· ftp[s]://host.xz[:port]/path/to/repo.git/
An alternative scp-like syntax may also be used with the ssh protocol:
· [user@]host.xz:path/to/repo.git/
This syntax is only recognized if there are no slashes before the first colon. This helps differentiate a local path that contains a
colon. For example the local path ffoooo::bbaarr could be specified as an absolute path or ..//ffoooo::bbaarr to avoid being misinterpreted as an ssh
url.
The ssh and git protocols additionally support ~username expansion:
· ssh://[user@]host.xz[:port]/~[user]/path/to/repo.git/
· git://host.xz[:port]/~[user]/path/to/repo.git/
· [user@]host.xz:/~[user]/path/to/repo.git/
For local repositories, also supported by Git natively, the following syntaxes may be used:
· /path/to/repo.git/
· file:///path/to/repo.git/
These two syntaxes are mostly equivalent, except when cloning, when the former implies --local option. See ggiitt--cclloonnee(1) for details.
When Git doesn’t know how to handle a certain transport protocol, it attempts to use the _r_e_m_o_t_e_-_<_t_r_a_n_s_p_o_r_t_> remote helper, if one
exists. To explicitly request a remote helper, the following syntax may be used:
· <transport>::<address>
where <address> may be a path, a server and path, or an arbitrary URL-like string recognized by the specific remote helper being
invoked. See ggiittrreemmoottee--hheellppeerrss(1) for details.
If there are a large number of similarly-named remote repositories and you want to use a different format for them (such that the
URLs you use will be rewritten into URLs that work), you can create a configuration section of the form:
[url "<actual url base>"]
insteadOf = <other url base>
For example, with this:
[url "git://git.host.xz/"]
insteadOf = host.xz:/path/to/
insteadOf = work:
a URL like "work:repo.git" or like "host.xz:/path/to/repo.git" will be rewritten in any context that takes a URL to be
"git://git.host.xz/repo.git".
If you want to rewrite URLs for push only, you can create a configuration section of the form:
[url "<actual url base>"]
pushInsteadOf = <other url base>
For example, with this:
[url "ssh://example.org/"]
pushInsteadOf = git://example.org/
a URL like "git://example.org/path/to/repo.git" will be rewritten to "ssh://example.org/path/to/repo.git" for pushes, but pulls will
still use the original URL.
RREEMMOOTTEESS
The name of one of the following can be used instead of a URL as <<rreeppoossiittoorryy>> argument:
· a remote in the Git configuration file: $$GGIITT__DDIIRR//ccoonnffiigg,
· a file in the $$GGIITT__DDIIRR//rreemmootteess directory, or
· a file in the $$GGIITT__DDIIRR//bbrraanncchheess directory.
All of these also allow you to omit the refspec from the command line because they each contain a refspec which git will use by
default.
NNaammeedd rreemmoottee iinn ccoonnffiigguurraattiioonn ffiillee
You can choose to provide the name of a remote which you had previously configured using ggiitt--rreemmoottee(1), ggiitt--ccoonnffiigg(1) or even by a
manual edit to the $$GGIITT__DDIIRR//ccoonnffiigg file. The URL of this remote will be used to access the repository. The refspec of this remote
will be used by default when you do not provide a refspec on the command line. The entry in the config file would appear like this:
[remote "<name>"]
url = <url>
pushurl = <pushurl>
push = <refspec>
fetch = <refspec>
The <<ppuusshhuurrll>> is used for pushes only. It is optional and defaults to <<uurrll>>.
NNaammeedd ffiillee iinn $$GGIITT__DDIIRR//rreemmootteess
You can choose to provide the name of a file in $$GGIITT__DDIIRR//rreemmootteess. The URL in this file will be used to access the repository. The
refspec in this file will be used as default when you do not provide a refspec on the command line. This file should have the
following format:
URL: one of the above URL format
Push: <refspec>
Pull: <refspec>
PPuusshh:: lines are used by _g_i_t _p_u_s_h and PPuullll:: lines are used by _g_i_t _p_u_l_l and _g_i_t _f_e_t_c_h. Multiple PPuusshh:: and PPuullll:: lines may be specified
for additional branch mappings.
NNaammeedd ffiillee iinn $$GGIITT__DDIIRR//bbrraanncchheess
You can choose to provide the name of a file in $$GGIITT__DDIIRR//bbrraanncchheess. The URL in this file will be used to access the repository. This
file should have the following format:
<url>#<head>
<<uurrll>> is required; ##<<hheeaadd>> is optional.
Depending on the operation, git will use one of the following refspecs, if you don’t provide one on the command line. <<bbrraanncchh>> is the
name of this file in $$GGIITT__DDIIRR//bbrraanncchheess and <<hheeaadd>> defaults to mmaasstteerr.
git fetch uses:
refs/heads/<head>:refs/heads/<branch>
git push uses:
HEAD:refs/heads/<head>
OOUUTTPPUUTT
The output of "git push" depends on the transport method used; this section describes the output when pushing over the Git protocol
(either locally or via ssh).
The status of the push is output in tabular form, with each line representing the status of a single ref. Each line is of the form:
<flag> <summary> <from> -> <to> (<reason>)
If --porcelain is used, then each line of the output is of the form:
<flag> \t <from>:<to> \t <summary> (<reason>)
The status of up-to-date refs is shown only if --porcelain or --verbose option is used.
flag
A single character indicating the status of the ref:
(space)
for a successfully pushed fast-forward;
++
for a successful forced update;
--
for a successfully deleted ref;
**
for a successfully pushed new ref;
!!
for a ref that was rejected or failed to push; and
==
for a ref that was up to date and did not need pushing.
summary
For a successfully pushed ref, the summary shows the old and new values of the ref in a form suitable for using as an argument to
ggiitt lloogg (this is <<oolldd>>....<<nneeww>> in most cases, and <<oolldd>>......<<nneeww>> for forced non-fast-forward updates).
For a failed update, more details are given:
rejected
Git did not try to send the ref at all, typically because it is not a fast-forward and you did not force the update.
remote rejected
The remote end refused the update. Usually caused by a hook on the remote side, or because the remote repository has one of
the following safety options in effect: rreecceeiivvee..ddeennyyCCuurrrreennttBBrraanncchh (for pushes to the checked out branch),
rreecceeiivvee..ddeennyyNNoonnFFaassttFFoorrwwaarrddss (for forced non-fast-forward updates), rreecceeiivvee..ddeennyyDDeelleetteess or rreecceeiivvee..ddeennyyDDeelleetteeCCuurrrreenntt. See ggiitt--
ccoonnffiigg(1).
remote failure
The remote end did not report the successful update of the ref, perhaps because of a temporary error on the remote side, a
break in the network connection, or other transient error.
from
The name of the local ref being pushed, minus its rreeffss//<<ttyyppee>>// prefix. In the case of deletion, the name of the local ref is
omitted.
to
The name of the remote ref being updated, minus its rreeffss//<<ttyyppee>>// prefix.
reason
A human-readable explanation. In the case of successfully pushed refs, no explanation is needed. For a failed ref, the reason for
failure is described.
NNOOTTEE AABBOOUUTT FFAASSTT--FFOORRWWAARRDDSS
When an update changes a branch (or more in general, a ref) that used to point at commit A to point at another commit B, it is called
a fast-forward update if and only if B is a descendant of A.
In a fast-forward update from A to B, the set of commits that the original commit A built on top of is a subset of the commits the
new commit B builds on top of. Hence, it does not lose any history.
In contrast, a non-fast-forward update will lose history. For example, suppose you and somebody else started at the same commit X,
and you built a history leading to commit B while the other person built a history leading to commit A. The history looks like this:
B
/
---X---A
Further suppose that the other person already pushed changes leading to A back to the original repository from which you two obtained
the original commit X.
The push done by the other person updated the branch that used to point at commit X to point at commit A. It is a fast-forward.
But if you try to push, you will attempt to update the branch (that now points at A) with commit B. This does _n_o_t fast-forward. If
you did so, the changes introduced by commit A will be lost, because everybody will now start building on top of B.
The command by default does not allow an update that is not a fast-forward to prevent such loss of history.
If you do not want to lose your work (history from X to B) or the work by the other person (history from X to A), you would need to
first fetch the history from the repository, create a history that contains changes done by both parties, and push the result back.
You can perform "git pull", resolve potential conflicts, and "git push" the result. A "git pull" will create a merge commit C between
commits A and B.
B---C
/ /
---X---A
Updating A with the resulting merge commit will fast-forward and your push will be accepted.
Alternatively, you can rebase your change between X and B on top of A, with "git pull --rebase", and push the result back. The rebase
will create a new commit D that builds the change between X and B on top of A.
B D
/ /
---X---A
Again, updating A with this commit will fast-forward and your push will be accepted.
There is another common situation where you may encounter non-fast-forward rejection when you try to push, and it is possible even
when you are pushing into a repository nobody else pushes into. After you push commit A yourself (in the first picture in this
section), replace it with "git commit --amend" to produce commit B, and you try to push it out, because forgot that you have pushed A
out already. In such a case, and only if you are certain that nobody in the meantime fetched your earlier commit A (and started
building on top of it), you can run "git push --force" to overwrite it. In other words, "git push --force" is a method reserved for a
case where you do mean to lose history.
EEXXAAMMPPLLEESS
ggiitt ppuusshh
Works like ggiitt ppuusshh <<rreemmoottee>>, where <remote> is the current branch’s remote (or oorriiggiinn, if no remote is configured for the
current branch).
ggiitt ppuusshh oorriiggiinn
Without additional configuration, pushes the current branch to the configured upstream (rreemmoottee..oorriiggiinn..mmeerrggee configuration
variable) if it has the same name as the current branch, and errors out without pushing otherwise.
The default behavior of this command when no <refspec> is given can be configured by setting the ppuusshh option of the remote, or
the ppuusshh..ddeeffaauulltt configuration variable.
For example, to default to pushing only the current branch to oorriiggiinn use ggiitt ccoonnffiigg rreemmoottee..oorriiggiinn..ppuusshh HHEEAADD. Any valid <refspec>
(like the ones in the examples below) can be configured as the default for ggiitt ppuusshh oorriiggiinn.
ggiitt ppuusshh oorriiggiinn ::
Push "matching" branches to oorriiggiinn. See <refspec> in the OPTIONS section above for a description of "matching" branches.
ggiitt ppuusshh oorriiggiinn mmaasstteerr
Find a ref that matches mmaasstteerr in the source repository (most likely, it would find rreeffss//hheeaaddss//mmaasstteerr), and update the same ref
(e.g. rreeffss//hheeaaddss//mmaasstteerr) in oorriiggiinn repository with it. If mmaasstteerr did not exist remotely, it would be created.
ggiitt ppuusshh oorriiggiinn HHEEAADD
A handy way to push the current branch to the same name on the remote.
ggiitt ppuusshh mmootthheerrsshhiipp mmaasstteerr::ssaatteelllliittee//mmaasstteerr ddeevv::ssaatteelllliittee//ddeevv
Use the source ref that matches mmaasstteerr (e.g. rreeffss//hheeaaddss//mmaasstteerr) to update the ref that matches ssaatteelllliittee//mmaasstteerr (most probably
rreeffss//rreemmootteess//ssaatteelllliittee//mmaasstteerr) in the mmootthheerrsshhiipp repository; do the same for ddeevv and ssaatteelllliittee//ddeevv.
This is to emulate ggiitt ffeettcchh run on the mmootthheerrsshhiipp using ggiitt ppuusshh that is run in the opposite direction in order to integrate the
work done on ssaatteelllliittee, and is often necessary when you can only make connection in one way (i.e. satellite can ssh into
mothership but mothership cannot initiate connection to satellite because the latter is behind a firewall or does not run sshd).
After running this ggiitt ppuusshh on the ssaatteelllliittee machine, you would ssh into the mmootthheerrsshhiipp and run ggiitt mmeerrggee there to complete the
emulation of ggiitt ppuullll that were run on mmootthheerrsshhiipp to pull changes made on ssaatteelllliittee.
ggiitt ppuusshh oorriiggiinn HHEEAADD::mmaasstteerr
Push the current branch to the remote ref matching mmaasstteerr in the oorriiggiinn repository. This form is convenient to push the current
branch without thinking about its local name.
ggiitt ppuusshh oorriiggiinn mmaasstteerr::rreeffss//hheeaaddss//eexxppeerriimmeennttaall
Create the branch eexxppeerriimmeennttaall in the oorriiggiinn repository by copying the current mmaasstteerr branch. This form is only needed to create
a new branch or tag in the remote repository when the local name and the remote name are different; otherwise, the ref name on
its own will work.
ggiitt ppuusshh oorriiggiinn ::eexxppeerriimmeennttaall
Find a ref that matches eexxppeerriimmeennttaall in the oorriiggiinn repository (e.g. rreeffss//hheeaaddss//eexxppeerriimmeennttaall), and delete it.
ggiitt ppuusshh oorriiggiinn ++ddeevv::mmaasstteerr
Update the origin repository’s master branch with the dev branch, allowing non-fast-forward updates. TThhiiss ccaann lleeaavvee uunnrreeffeerreenncceedd
ccoommmmiittss ddaanngglliinngg iinn tthhee oorriiggiinn rreeppoossiittoorryy.. Consider the following situation, where a fast-forward is not possible:
o---o---o---A---B origin/master
\
X---Y---Z dev
The above command would change the origin repository to
A---B (unnamed branch)
/
o---o---o---X---Y---Z master
Commits A and B would no longer belong to a branch with a symbolic name, and so would be unreachable. As such, these commits
would be removed by a ggiitt ggcc command on the origin repository.
SSEECCUURRIITTYY
The fetch and push protocols are not designed to prevent one side from stealing data from the other repository that was not intended
to be shared. If you have private data that you need to protect from a malicious peer, your best option is to store it in another
repository. This applies to both clients and servers. In particular, namespaces on a server are not effective for read access
control; you should only grant read access to a namespace to clients that you would trust with read access to the entire repository.
The known attack vectors are as follows:
1. The victim sends "have" lines advertising the IDs of objects it has that are not explicitly intended to be shared but can be used
to optimize the transfer if the peer also has them. The attacker chooses an object ID X to steal and sends a ref to X, but isn’t
required to send the content of X because the victim already has it. Now the victim believes that the attacker has X, and it
sends the content of X back to the attacker later. (This attack is most straightforward for a client to perform on a server, by
creating a ref to X in the namespace the client has access to and then fetching it. The most likely way for a server to perform
it on a client is to "merge" X into a public branch and hope that the user does additional work on this branch and pushes it back
to the server without noticing the merge.)
2. As in #1, the attacker chooses an object ID X to steal. The victim sends an object Y that the attacker already has, and the
attacker falsely claims to have X and not Y, so the victim sends Y as a delta against X. The delta reveals regions of X that are
similar to Y to the attacker.
GGIITT
Part of the ggiitt(1) suite
Git 2.17.1 05/31/2018 GIT-PUSH(1)