git-credential - Retrieve and store user credentials
git credential <fill|approve|reject>
Git has an internal interface for storing and retrieving credentials from
system-specific helpers, as well as prompting the user for usernames and
passwords. The git-credential command exposes this interface to scripts which
may want to retrieve, store, or prompt for credentials in the same manner as
Git. The design of this scriptable interface models the internal C API; see
the Git credential API for more background on the concepts.
git-credential takes an "action" option on the
command-line (one of fill, approve, or reject) and
reads a credential description on stdin (see INPUT/OUTPUT FORMAT).
If the action is fill, git-credential will attempt to add
"username" and "password" attributes to the description
by reading config files, by contacting any configured credential helpers, or
by prompting the user. The username and password attributes of the
credential description are then printed to stdout together with the
attributes already provided.
If the action is approve, git-credential will send the
description to any configured credential helpers, which may store the
credential for later use.
If the action is reject, git-credential will send the
description to any configured credential helpers, which may erase any stored
credential matching the description.
If the action is approve or reject, no output should
An application using git-credential will typically use git credential
following these steps:
1.Generate a credential description based on the
For example, if we want a password for
https://example.com/foo.git, we might generate the following
credential description (don’t forget the blank line at the end; it
tells git credential that the application finished feeding all the
information it has):
2.Ask git-credential to give us a username and password
for this description. This is done by running git credential fill
feeding the description from step (1) to its standard input. The complete
credential description (including the credential per se, i.e. the login and
password) will be produced on standard output, like:
In most cases, this means the attributes given in the input will
be repeated in the output, but Git may also modify the credential
description, for example by removing the path attribute when the
protocol is HTTP(s) and credential.useHttpPath is false.
If the git credential knew about the password, this step
may not have involved the user actually typing this password (the user may
have typed a password to unlock the keychain instead, or no user interaction
was done if the keychain was already unlocked) before it returned
3.Use the credential (e.g., access the URL with the
username and password from step (2)), and see if it’s accepted.
4.Report on the success or failure of the password. If
the credential allowed the operation to complete successfully, then it can be
marked with an "approve" action to tell git credential to
reuse it in its next invocation. If the credential was rejected during the
operation, use the "reject" action so that git credential
will ask for a new password in its next invocation. In either case, git
credential should be fed with the credential description obtained from
step (2) (which also contain the ones provided in step (1)).
git credential reads and/or writes (depending on the action used)
credential information in its standard input/output. This information can
correspond either to keys for which git credential will obtain the
login/password information (e.g. host, protocol, path), or to the actual
credential data to be obtained (login/password).
The credential is split into a set of named attributes, with one
attribute per line. Each attribute is specified by a key-value pair,
separated by an = (equals) sign, followed by a newline. The key may
contain any bytes except =, newline, or NUL. The value may contain
any bytes except newline or NUL. In both cases, all bytes are treated as-is
(i.e., there is no quoting, and one cannot transmit a value with newline or
NUL in it). The list of attributes is terminated by a blank line or
end-of-file. Git understands the following attributes:
The protocol over which the credential will be used
The remote hostname for a network credential.
The path with which the credential will be used. E.g.,
for accessing a remote https repository, this will be the repository’s
path on the server.
The credential’s username, if we already have one
(e.g., from a URL, from the user, or from a previously run helper).
The credential’s password, if we are asking it to
When this special attribute is read by git
credential, the value is parsed as a URL and treated as if its constituent
parts were read (e.g., url=https://example.com would behave as if
protocol=https and host=example.com had been provided). This can
help callers avoid parsing URLs themselves. Note that any components which are
missing from the URL (e.g., there is no username in the example above) will be
set to empty; if you want to provide a URL and override some attributes,
provide the URL attribute first, followed by any overrides.
- the Git credential API