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 credential.h for more
  23 background on the concepts.
  24
  25 git-credential takes an "action" option on the command-line (one of
  26 `fill`, `approve`, or `reject`) and reads a credential description
  27 on stdin (see <<IOFMT,INPUT/OUTPUT FORMAT>>).
  28
  29 If the action is `fill`, git-credential will attempt to add "username"
  30 and "password" attributes to the description by reading config files,
  31 by contacting any configured credential helpers, or by prompting the
  32 user. The username and password attributes of the credential
  33 description are then printed to stdout together with the attributes
  34 already provided.
  35
  36 If the action is `approve`, git-credential will send the description
  37 to any configured credential helpers, which may store the credential
  38 for later use.
  39
  40 If the action is `reject`, git-credential will send the description to
  41 any configured credential helpers, which may erase any stored
  42 credential matching the description.
  43
  44 If the action is `approve` or `reject`, no output should be emitted.
  45
  46 TYPICAL USE OF GIT CREDENTIAL
  47 -----------------------------
  48
  49 An application using git-credential will typically use `git
  50 credential` following these steps:
  51
  52   1. Generate a credential description based on the context.
  53 +
  54 For example, if we want a password for
  55 `https://example.com/foo.git`, we might generate the following
  56 credential description (don't forget the blank line at the end; it
  57 tells `git credential` that the application finished feeding all the
  58 information it has):
  59
  60          protocol=https
  61          host=example.com
  62          path=foo.git
  63
  64   2. Ask git-credential to give us a username and password for this
  65      description. This is done by running `git credential fill`,
  66      feeding the description from step (1) to its standard input. The complete
  67      credential description (including the credential per se, i.e. the
  68      login and password) will be produced on standard output, like:
  69
  70         protocol=https
  71         host=example.com
  72         username=bob
  73         password=secr3t
  74 +
  75 In most cases, this means the attributes given in the input will be
  76 repeated in the output, but Git may also modify the credential
  77 description, for example by removing the `path` attribute when the
  78 protocol is HTTP(s) and `credential.useHttpPath` is false.
  79 +
  80 If the `git credential` knew about the password, this step may
  81 not have involved the user actually typing this password (the
  82 user may have typed a password to unlock the keychain instead,
  83 or no user interaction was done if the keychain was already
  84 unlocked) before it returned `password=secr3t`.
  85
  86   3. Use the credential (e.g., access the URL with the username and
  87      password from step (2)), and see if it's accepted.
  88
  89   4. Report on the success or failure of the password. If the
  90      credential allowed the operation to complete successfully, then
  91      it can be marked with an "approve" action to tell `git
  92      credential` to reuse it in its next invocation. If the credential
  93      was rejected during the operation, use the "reject" action so
  94      that `git credential` will ask for a new password in its next
  95      invocation. In either case, `git credential` should be fed with
  96      the credential description obtained from step (2) (which also
  97      contain the ones provided in step (1)).
  98
  99 [[IOFMT]]
 100 INPUT/OUTPUT FORMAT
 101 -------------------
 102
 103 `git credential` reads and/or writes (depending on the action used)
 104 credential information in its standard input/output. This information
 105 can correspond either to keys for which `git credential` will obtain
 106 the login information (e.g. host, protocol, path), or to the actual
 107 credential data to be obtained (username/password).
 108
 109 The credential is split into a set of named attributes, with one
 110 attribute per line. Each attribute is specified by a key-value pair,
 111 separated by an `=` (equals) sign, followed by a newline.
 112
 113 The key may contain any bytes except `=`, newline, or NUL. The value may
 114 contain any bytes except newline or NUL.
 115
 116 In both cases, all bytes are treated as-is (i.e., there is no quoting,
 117 and one cannot transmit a value with newline or NUL in it). The list of
 118 attributes is terminated by a blank line or end-of-file.
 119
 120 Git understands the following attributes:
 121
 122 `protocol`::
 123
 124         The protocol over which the credential will be used (e.g.,
 125         `https`).
 126
 127 `host`::
 128
 129         The remote hostname for a network credential.  This includes
 130         the port number if one was specified (e.g., "example.com:8088").
 131
 132 `path`::
 133
 134         The path with which the credential will be used. E.g., for
 135         accessing a remote https repository, this will be the
 136         repository's path on the server.
 137
 138 `username`::
 139
 140         The credential's username, if we already have one (e.g., from a
 141         URL, the configuration, the user, or from a previously run helper).
 142
 143 `password`::
 144
 145         The credential's password, if we are asking it to be stored.
 146
 147 `url`::
 148
 149         When this special attribute is read by `git credential`, the
 150         value is parsed as a URL and treated as if its constituent parts
 151         were read (e.g., `url=https://example.com` would behave as if
 152         `protocol=https` and `host=example.com` had been provided). This
 153         can help callers avoid parsing URLs themselves.
 154 +
 155 Note that specifying a protocol is mandatory and if the URL
 156 doesn't specify a hostname (e.g., "cert:///path/to/file") the
 157 credential will contain a hostname attribute whose value is an
 158 empty string.
 159 +
 160 Components which are missing from the URL (e.g., there is no
 161 username in the example above) will be left unset.