git credential fill: output the whole 'struct credential'
[git/git.git] / 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.txt[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 infomation 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. These 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.
111 Attributes are provided to the helper, one 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 will send the following attributes (but may not send all of
119 them for a given credential; for example, a `host` attribute makes no
120 sense when dealing with a non-network protocol):
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.
130
131 `path`::
132
133 The path with which the credential will be used. E.g., for
134 accessing a remote https repository, this will be the
135 repository's path on the server.
136
137 `username`::
138
139 The credential's username, if we already have one (e.g., from a
140 URL, from the user, or from a previously run helper).
141
142 `password`::
143
144 The credential's password, if we are asking it to be stored.