Documentation/git-credential.txt

   1 git-credential(1)
   2 =================
   3
   4 NAME
   5 ----
   6 git-credential - Retrieve and store user credentials
   7
   8 SYNOPSIS
   9 --------
  10 ------------------
  11 git credential <fill|approve|reject>
  12 ------------------
  13
  14 DESCRIPTION
  15 -----------
  16
  17 Git has an internal interface for storing and retrieving credentials
  18 from system-specific helpers, as well as prompting the user for
  19 usernames and passwords. The git-credential command exposes this
  20 interface to scripts which may want to retrieve, store, or prompt for
  21 credentials in the same manner as Git. The design of this scriptable
  22 interface models the internal C API; see
  23 link:technical/api-credentials.html[the Git credential API] for more
  24 background on the concepts.
  25
  26 git-credential takes an "action" option on the command-line (one of
  27 `fill`, `approve`, or `reject`) and reads a credential description
  28 on stdin (see <<IOFMT,INPUT/OUTPUT FORMAT>>).
  29
  30 If the action is `fill`, git-credential will attempt to add "username"
  31 and "password" attributes to the description by reading config files,
  32 by contacting any configured credential helpers, or by prompting the
  33 user. The username and password attributes of the credential
  34 description are then printed to stdout together with the attributes
  35 already provided.
  36
  37 If the action is `approve`, git-credential will send the description
  38 to any configured credential helpers, which may store the credential
  39 for later use.
  40
  41 If the action is `reject`, git-credential will send the description to
  42 any configured credential helpers, which may erase any stored
  43 credential matching the description.
  44
  45 If the action is `approve` or `reject`, no output should be emitted.
  46
  47 TYPICAL USE OF GIT CREDENTIAL
  48 -----------------------------
  49
  50 An application using git-credential will typically use `git
  51 credential` following these steps:
  52
  53   1. Generate a credential description based on the context.
  54 +
  55 For example, if we want a password for
  56 `https://example.com/foo.git`, we might generate the following
  57 credential description (don't forget the blank line at the end; it
  58 tells `git credential` that the application finished feeding all the
  59 information it has):
  60
  61          protocol=https
  62          host=example.com
  63          path=foo.git
  64
  65   2. Ask git-credential to give us a username and password for this
  66      description. This is done by running `git credential fill`,
  67      feeding the description from step (1) to its standard input. The complete
  68      credential description (including the credential per se, i.e. the
  69      login and password) will be produced on standard output, like:
  70
  71         protocol=https
  72         host=example.com
  73         username=bob
  74         password=secr3t
  75 +
  76 In most cases, this means the attributes given in the input will be
  77 repeated in the output, but Git may also modify the credential
  78 description, for example by removing the `path` attribute when the
  79 protocol is HTTP(s) and `credential.useHttpPath` is false.
  80 +
  81 If the `git credential` knew about the password, this step may
  82 not have involved the user actually typing this password (the
  83 user may have typed a password to unlock the keychain instead,
  84 or no user interaction was done if the keychain was already
  85 unlocked) before it returned `password=secr3t`.
  86
  87   3. Use the credential (e.g., access the URL with the username and
  88      password from step (2)), and see if it's accepted.
  89
  90   4. Report on the success or failure of the password. If the
  91      credential allowed the operation to complete successfully, then
  92      it can be marked with an "approve" action to tell `git
  93      credential` to reuse it in its next invocation. If the credential
  94      was rejected during the operation, use the "reject" action so
  95      that `git credential` will ask for a new password in its next
  96      invocation. In either case, `git credential` should be fed with
  97      the credential description obtained from step (2) (which also
  98      contain the ones provided in step (1)).
  99
 100 [[IOFMT]]
 101 INPUT/OUTPUT FORMAT
 102 -------------------
 103
 104 `git credential` reads and/or writes (depending on the action used)
 105 credential information in its standard input/output. This information
 106 can correspond either to keys for which `git credential` will obtain
 107 the login/password information (e.g. host, protocol, path), or to the
 108 actual credential data to be obtained (login/password).
 109
 110 The credential is split into a set of named attributes, with one
 111 attribute per line. Each attribute is
 112 specified by a key-value pair, separated by an `=` (equals) sign,
 113 followed by a newline. The key may contain any bytes except `=`,
 114 newline, or NUL. The value may contain any bytes except newline or NUL.
 115 In both cases, all bytes are treated as-is (i.e., there is no quoting,
 116 and one cannot transmit a value with newline or NUL in it). The list of
 117 attributes is terminated by a blank line or end-of-file.
 118 Git understands the following attributes:
 119
 120 `protocol`::
 121
 122         The protocol over which the credential will be used (e.g.,
 123         `https`).
 124
 125 `host`::
 126
 127         The remote hostname for a network credential.
 128
 129 `path`::
 130
 131         The path with which the credential will be used. E.g., for
 132         accessing a remote https repository, this will be the
 133         repository's path on the server.
 134
 135 `username`::
 136
 137         The credential's username, if we already have one (e.g., from a
 138         URL, from the user, or from a previously run helper).
 139
 140 `password`::
 141
 142         The credential's password, if we are asking it to be stored.
 143
 144 `url`::
 145
 146         When this special attribute is read by `git credential`, the
 147         value is parsed as a URL and treated as if its constituent parts
 148         were read (e.g., `url=https://example.com` would behave as if
 149         `protocol=https` and `host=example.com` had been provided). This
 150         can help callers avoid parsing URLs themselves.  Note that any
 151         components which are missing from the URL (e.g., there is no
 152         username in the example above) will be set to empty; if you want
 153         to provide a URL and override some attributes, provide the URL
 154         attribute first, followed by any overrides.