]>
Commit | Line | Data |
---|---|---|
6eb996b5 DB |
1 | git-remote-helpers(1) |
2 | ===================== | |
3 | ||
4 | NAME | |
5 | ---- | |
00b84e9d | 6 | git-remote-helpers - Helper programs to interact with remote repositories |
6eb996b5 DB |
7 | |
8 | SYNOPSIS | |
9 | -------- | |
7791a1d9 | 10 | [verse] |
b6c8d2d6 | 11 | 'git remote-<transport>' <repository> [<URL>] |
6eb996b5 DB |
12 | |
13 | DESCRIPTION | |
14 | ----------- | |
15 | ||
00b84e9d RR |
16 | Remote helper programs are normally not used directly by end users, |
17 | but they are invoked by git when it needs to interact with remote | |
18 | repositories git does not support natively. A given helper will | |
19 | implement a subset of the capabilities documented here. When git | |
20 | needs to interact with a repository using a remote helper, it spawns | |
21 | the helper as an independent process, sends commands to the helper's | |
22 | standard input, and expects results from the helper's standard | |
23 | output. Because a remote helper runs as an independent process from | |
24 | git, there is no need to re-link git to add a new helper, nor any | |
25 | need to link the helper with the implementation of git. | |
26 | ||
b4fc8d6a JN |
27 | Every helper must support the "capabilities" command, which git |
28 | uses to determine what other commands the helper will accept. Those | |
29 | other commands can be used to discover and update remote refs, | |
30 | transport objects between the object database and the remote repository, | |
31 | and update the local object store. | |
00b84e9d RR |
32 | |
33 | Git comes with a "curl" family of remote helpers, that handle various | |
34 | transport protocols, such as 'git-remote-http', 'git-remote-https', | |
35 | 'git-remote-ftp' and 'git-remote-ftps'. They implement the capabilities | |
36 | 'fetch', 'option', and 'push'. | |
6eb996b5 | 37 | |
f829a9ea MH |
38 | INVOCATION |
39 | ---------- | |
40 | ||
41 | Remote helper programs are invoked with one or (optionally) two | |
42 | arguments. The first argument specifies a remote repository as in git; | |
43 | it is either the name of a configured remote or a URL. The second | |
44 | argument specifies a URL; it is usually of the form | |
45 | '<transport>://<address>', but any arbitrary string is possible. | |
46 | The 'GIT_DIR' environment variable is set up for the remote helper | |
47 | and can be used to determine where to store additional data or from | |
48 | which directory to invoke auxiliary git commands. | |
49 | ||
50 | When git encounters a URL of the form '<transport>://<address>', where | |
51 | '<transport>' is a protocol that it cannot handle natively, it | |
52 | automatically invokes 'git remote-<transport>' with the full URL as | |
53 | the second argument. If such a URL is encountered directly on the | |
54 | command line, the first argument is the same as the second, and if it | |
55 | is encountered in a configured remote, the first argument is the name | |
56 | of that remote. | |
57 | ||
58 | A URL of the form '<transport>::<address>' explicitly instructs git to | |
59 | invoke 'git remote-<transport>' with '<address>' as the second | |
60 | argument. If such a URL is encountered directly on the command line, | |
61 | the first argument is '<address>', and if it is encountered in a | |
62 | configured remote, the first argument is the name of that remote. | |
63 | ||
64 | Additionally, when a configured remote has 'remote.<name>.vcs' set to | |
65 | '<transport>', git explicitly invokes 'git remote-<transport>' with | |
66 | '<name>' as the first argument. If set, the second argument is | |
67 | 'remote.<name>.url'; otherwise, the second argument is omitted. | |
68 | ||
b4fc8d6a JN |
69 | INPUT FORMAT |
70 | ------------ | |
71 | ||
72 | Git sends the remote helper a list of commands on standard input, one | |
73 | per line. The first command is always the 'capabilities' command, in | |
74 | response to which the remote helper must print a list of the | |
75 | capabilities it supports (see below) followed by a blank line. The | |
76 | response to the capabilities command determines what commands Git uses | |
77 | in the remainder of the command stream. | |
78 | ||
79 | The command stream is terminated by a blank line. In some cases | |
80 | (indicated in the documentation of the relevant commands), this blank | |
81 | line is followed by a payload in some other protocol (e.g., the pack | |
82 | protocol), while in others it indicates the end of input. | |
83 | ||
84 | Capabilities | |
85 | ~~~~~~~~~~~~ | |
86 | ||
87 | Each remote helper is expected to support only a subset of commands. | |
88 | The operations a helper supports are declared to git in the response | |
89 | to the `capabilities` command (see COMMANDS, below). | |
90 | ||
0673bb28 MH |
91 | In the following, we list all defined capabilities and for |
92 | each we list which commands a helper with that capability | |
93 | must provide. | |
b4b106e5 | 94 | |
b4fc8d6a | 95 | Capabilities for Pushing |
0673bb28 | 96 | ^^^^^^^^^^^^^^^^^^^^^^^^ |
b4fc8d6a JN |
97 | 'connect':: |
98 | Can attempt to connect to 'git receive-pack' (for pushing), | |
0673bb28 MH |
99 | 'git upload-pack', etc for communication using |
100 | git's native packfile protocol. This | |
101 | requires a bidirectional, full-duplex connection. | |
b4fc8d6a JN |
102 | + |
103 | Supported commands: 'connect'. | |
104 | ||
105 | 'push':: | |
106 | Can discover remote refs and push local commits and the | |
107 | history leading up to them to new or existing remote refs. | |
108 | + | |
109 | Supported commands: 'list for-push', 'push'. | |
110 | ||
b4b106e5 MH |
111 | 'export':: |
112 | Can discover remote refs and push specified objects from a | |
113 | fast-import stream to remote refs. | |
114 | + | |
115 | Supported commands: 'list for-push', 'export'. | |
116 | ||
117 | If a helper advertises 'connect', git will use it if possible and | |
118 | fall back to another capability if the helper requests so when | |
119 | connecting (see the 'connect' command under COMMANDS). | |
120 | When choosing between 'push' and 'export', git prefers 'push'. | |
121 | Other frontends may have some other order of preference. | |
122 | ||
b4fc8d6a JN |
123 | |
124 | Capabilities for Fetching | |
0673bb28 | 125 | ^^^^^^^^^^^^^^^^^^^^^^^^^ |
b4fc8d6a JN |
126 | 'connect':: |
127 | Can try to connect to 'git upload-pack' (for fetching), | |
128 | 'git receive-pack', etc for communication using the | |
0673bb28 MH |
129 | git's native packfile protocol. This |
130 | requires a bidirectional, full-duplex connection. | |
b4fc8d6a JN |
131 | + |
132 | Supported commands: 'connect'. | |
133 | ||
134 | 'fetch':: | |
135 | Can discover remote refs and transfer objects reachable from | |
136 | them to the local object store. | |
137 | + | |
138 | Supported commands: 'list', 'fetch'. | |
139 | ||
140 | 'import':: | |
141 | Can discover remote refs and output objects reachable from | |
142 | them as a stream in fast-import format. | |
143 | + | |
144 | Supported commands: 'list', 'import'. | |
145 | ||
146 | If a helper advertises 'connect', git will use it if possible and | |
147 | fall back to another capability if the helper requests so when | |
148 | connecting (see the 'connect' command under COMMANDS). | |
149 | When choosing between 'fetch' and 'import', git prefers 'fetch'. | |
150 | Other frontends may have some other order of preference. | |
151 | ||
0673bb28 MH |
152 | Miscellaneous capabilities |
153 | ^^^^^^^^^^^^^^^^^^^^^^^^^^ | |
154 | ||
155 | 'option':: | |
156 | For specifying settings like `verbosity` (how much output to | |
157 | write to stderr) and `depth` (how much history is wanted in the | |
158 | case of a shallow clone) that affect how other commands are | |
159 | carried out. | |
160 | ||
b4fc8d6a | 161 | 'refspec' <refspec>:: |
0673bb28 MH |
162 | This modifies the 'import' capability, allowing the produced |
163 | fast-import stream to modify refs in a private namespace | |
164 | instead of writing to refs/heads or refs/remotes directly. | |
165 | It is recommended that all importers providing the 'import' | |
166 | capability use this. | |
b4fc8d6a | 167 | + |
0673bb28 | 168 | A helper advertising the capability |
6cf378f0 | 169 | `refspec refs/heads/*:refs/svn/origin/branches/*` |
0673bb28 MH |
170 | is saying that, when it is asked to `import refs/heads/topic`, the |
171 | stream it outputs will update the `refs/svn/origin/branches/topic` | |
172 | ref. | |
b4fc8d6a JN |
173 | + |
174 | This capability can be advertised multiple times. The first | |
175 | applicable refspec takes precedence. The left-hand of refspecs | |
176 | advertised with this capability must cover all refs reported by | |
177 | the list command. If no 'refspec' capability is advertised, | |
6cf378f0 | 178 | there is an implied `refspec *:*`. |
b4fc8d6a | 179 | |
0673bb28 MH |
180 | 'bidi-import':: |
181 | This modifies the 'import' capability. | |
182 | The fast-import commands 'cat-blob' and 'ls' can be used by remote-helpers | |
183 | to retrieve information about blobs and trees that already exist in | |
184 | fast-import's memory. This requires a channel from fast-import to the | |
185 | remote-helper. | |
186 | If it is advertised in addition to "import", git establishes a pipe from | |
187 | fast-import to the remote-helper's stdin. | |
188 | It follows that git and fast-import are both connected to the | |
189 | remote-helper's stdin. Because git can send multiple commands to | |
190 | the remote-helper it is required that helpers that use 'bidi-import' | |
191 | buffer all 'import' commands of a batch before sending data to fast-import. | |
192 | This is to prevent mixing commands and fast-import responses on the | |
193 | helper's stdin. | |
194 | ||
195 | 'export-marks' <file>:: | |
196 | This modifies the 'export' capability, instructing git to dump the | |
197 | internal marks table to <file> when complete. For details, | |
198 | read up on '--export-marks=<file>' in linkgit:git-fast-export[1]. | |
199 | ||
200 | 'import-marks' <file>:: | |
201 | This modifies the 'export' capability, instructing git to load the | |
202 | marks specified in <file> before processing any input. For details, | |
203 | read up on '--import-marks=<file>' in linkgit:git-fast-export[1]. | |
204 | ||
205 | ||
206 | ||
207 | ||
6eb996b5 DB |
208 | COMMANDS |
209 | -------- | |
210 | ||
211 | Commands are given by the caller on the helper's standard input, one per line. | |
212 | ||
213 | 'capabilities':: | |
214 | Lists the capabilities of the helper, one per line, ending | |
d43427d3 | 215 | with a blank line. Each capability may be preceded with '*', |
b20c457a MH |
216 | which marks them mandatory for git versions using the remote |
217 | helper to understand. Any unknown mandatory capability is a | |
218 | fatal error. | |
754cb1ae MH |
219 | + |
220 | Support for this command is mandatory. | |
6eb996b5 DB |
221 | |
222 | 'list':: | |
223 | Lists the refs, one per line, in the format "<value> <name> | |
224 | [<attr> ...]". The value may be a hex sha1 hash, "@<dest>" for | |
225 | a symref, or "?" to indicate that the helper could not get the | |
226 | value of the ref. A space-separated list of attributes follows | |
d43427d3 RR |
227 | the name; unrecognized attributes are ignored. The list ends |
228 | with a blank line. | |
ae4efe19 | 229 | + |
9ec8bcda MH |
230 | See REF LIST ATTRIBUTES for a list of currently defined attributes. |
231 | + | |
754cb1ae MH |
232 | Supported if the helper has the "fetch" or "import" capability. |
233 | ||
234 | 'list for-push':: | |
235 | Similar to 'list', except that it is used if and only if | |
236 | the caller wants to the resulting ref list to prepare | |
237 | push commands. | |
238 | A helper supporting both push and fetch can use this | |
239 | to distinguish for which operation the output of 'list' | |
240 | is going to be used, possibly reducing the amount | |
241 | of work that needs to be performed. | |
242 | + | |
243 | Supported if the helper has the "push" or "export" capability. | |
6eb996b5 | 244 | |
ef08ef9e | 245 | 'option' <name> <value>:: |
d43427d3 | 246 | Sets the transport helper option <name> to <value>. Outputs a |
ef08ef9e SP |
247 | single line containing one of 'ok' (option successfully set), |
248 | 'unsupported' (option not recognized) or 'error <msg>' | |
d43427d3 | 249 | (option <name> is supported but <value> is not valid |
ef08ef9e | 250 | for it). Options should be set before other commands, |
d43427d3 | 251 | and may influence the behavior of those commands. |
ef08ef9e | 252 | + |
9ec8bcda MH |
253 | See OPTIONS for a list of currently defined options. |
254 | + | |
ef08ef9e | 255 | Supported if the helper has the "option" capability. |
6eb996b5 DB |
256 | |
257 | 'fetch' <sha1> <name>:: | |
292ce46b SP |
258 | Fetches the given object, writing the necessary objects |
259 | to the database. Fetch commands are sent in a batch, one | |
d43427d3 | 260 | per line, terminated with a blank line. |
292ce46b SP |
261 | Outputs a single blank line when all fetch commands in the |
262 | same batch are complete. Only objects which were reported | |
9ec8bcda | 263 | in the output of 'list' with a sha1 may be fetched this way. |
292ce46b SP |
264 | + |
265 | Optionally may output a 'lock <file>' line indicating a file under | |
266 | GIT_DIR/objects/pack which is keeping a pack until refs can be | |
267 | suitably updated. | |
6eb996b5 DB |
268 | + |
269 | Supported if the helper has the "fetch" capability. | |
270 | ||
ae4efe19 | 271 | 'push' +<src>:<dst>:: |
d43427d3 | 272 | Pushes the given local <src> commit or branch to the |
ae4efe19 | 273 | remote branch described by <dst>. A batch sequence of |
960e3114 MM |
274 | one or more 'push' commands is terminated with a blank line |
275 | (if there is only one reference to push, a single 'push' command | |
276 | is followed by a blank line). For example, the following would | |
277 | be two batches of 'push', the first asking the remote-helper | |
278 | to push the local ref 'master' to the remote ref 'master' and | |
279 | the local 'HEAD' to the remote 'branch', and the second | |
280 | asking to push ref 'foo' to ref 'bar' (forced update requested | |
281 | by the '+'). | |
282 | + | |
283 | ------------ | |
284 | push refs/heads/master:refs/heads/master | |
285 | push HEAD:refs/heads/branch | |
286 | \n | |
287 | push +refs/heads/foo:refs/heads/bar | |
288 | \n | |
289 | ------------ | |
ae4efe19 SP |
290 | + |
291 | Zero or more protocol options may be entered after the last 'push' | |
292 | command, before the batch's terminating blank line. | |
293 | + | |
294 | When the push is complete, outputs one or more 'ok <dst>' or | |
295 | 'error <dst> <why>?' lines to indicate success or failure of | |
296 | each pushed ref. The status report output is terminated by | |
297 | a blank line. The option field <why> may be quoted in a C | |
298 | style string if it contains an LF. | |
299 | + | |
300 | Supported if the helper has the "push" capability. | |
301 | ||
e65e91ed DB |
302 | 'import' <name>:: |
303 | Produces a fast-import stream which imports the current value | |
304 | of the named ref. It may additionally import other refs as | |
72ff8943 DB |
305 | needed to construct the history efficiently. The script writes |
306 | to a helper-specific private namespace. The value of the named | |
307 | ref should be written to a location in this namespace derived | |
308 | by applying the refspecs from the "refspec" capability to the | |
309 | name of the ref. | |
e65e91ed | 310 | + |
d43427d3 RR |
311 | Especially useful for interoperability with a foreign versioning |
312 | system. | |
313 | + | |
960e3114 MM |
314 | Just like 'push', a batch sequence of one or more 'import' is |
315 | terminated with a blank line. For each batch of 'import', the remote | |
316 | helper should produce a fast-import stream terminated by a 'done' | |
317 | command. | |
318 | + | |
271bfd67 FA |
319 | Note that if the 'bidi-import' capability is used the complete batch |
320 | sequence has to be buffered before starting to send data to fast-import | |
321 | to prevent mixing of commands and fast-import responses on the helper's | |
322 | stdin. | |
323 | + | |
754cb1ae | 324 | Supported if the helper has the "import" capability. |
e65e91ed | 325 | |
b4b106e5 MH |
326 | 'export':: |
327 | Instructs the remote helper that any subsequent input is | |
328 | part of a fast-import stream (generated by 'git fast-export') | |
329 | containing objects which should be pushed to the remote. | |
330 | + | |
331 | Especially useful for interoperability with a foreign versioning | |
332 | system. | |
333 | + | |
334 | The 'export-marks' and 'import-marks' capabilities, if specified, | |
335 | affect this command in so far as they are passed on to 'git | |
336 | fast-export', which then will load/store a table of marks for | |
337 | local objects. This can be used to implement for incremental | |
338 | operations. | |
339 | + | |
754cb1ae | 340 | Supported if the helper has the "export" capability. |
b4b106e5 | 341 | |
fa8c097c IL |
342 | 'connect' <service>:: |
343 | Connects to given service. Standard input and standard output | |
344 | of helper are connected to specified service (git prefix is | |
345 | included in service name so e.g. fetching uses 'git-upload-pack' | |
346 | as service) on remote side. Valid replies to this command are | |
347 | empty line (connection established), 'fallback' (no smart | |
348 | transport support, fall back to dumb transports) and just | |
349 | exiting with error message printed (can't connect, don't | |
350 | bother trying to fall back). After line feed terminating the | |
351 | positive (empty) response, the output of service starts. After | |
352 | the connection ends, the remote helper exits. | |
353 | + | |
354 | Supported if the helper has the "connect" capability. | |
355 | ||
6eb996b5 DB |
356 | If a fatal error occurs, the program writes the error message to |
357 | stderr and exits. The caller should expect that a suitable error | |
358 | message has been printed if the child closes the connection without | |
359 | completing a valid response for the current command. | |
360 | ||
361 | Additional commands may be supported, as may be determined from | |
362 | capabilities reported by the helper. | |
363 | ||
6eb996b5 DB |
364 | REF LIST ATTRIBUTES |
365 | ------------------- | |
366 | ||
9ec8bcda MH |
367 | The 'list' command produces a list of refs in which each ref |
368 | may be followed by a list of attributes. The following ref list | |
369 | attributes are defined. | |
6eb996b5 | 370 | |
f8ec9167 DB |
371 | 'unchanged':: |
372 | This ref is unchanged since the last import or fetch, although | |
373 | the helper cannot necessarily determine what value that produced. | |
6eb996b5 | 374 | |
ef08ef9e SP |
375 | OPTIONS |
376 | ------- | |
9ec8bcda MH |
377 | |
378 | The following options are defined and (under suitable circumstances) | |
379 | set by git if the remote helper has the 'option' capability. | |
380 | ||
3b0d2405 | 381 | 'option verbosity' <n>:: |
d43427d3 | 382 | Changes the verbosity of messages displayed by the helper. |
3b0d2405 | 383 | A value of 0 for <n> means that processes operate |
d43427d3 RR |
384 | quietly, and the helper produces only error output. |
385 | 1 is the default level of verbosity, and higher values | |
3b0d2405 | 386 | of <n> correspond to the number of -v flags passed on the |
ef08ef9e SP |
387 | command line. |
388 | ||
389 | 'option progress' \{'true'|'false'\}:: | |
d43427d3 | 390 | Enables (or disables) progress messages displayed by the |
ef08ef9e SP |
391 | transport helper during a command. |
392 | ||
393 | 'option depth' <depth>:: | |
d43427d3 | 394 | Deepens the history of a shallow repository. |
ef08ef9e SP |
395 | |
396 | 'option followtags' \{'true'|'false'\}:: | |
397 | If enabled the helper should automatically fetch annotated | |
398 | tag objects if the object the tag points at was transferred | |
399 | during the fetch command. If the tag is not fetched by | |
400 | the helper a second fetch command will usually be sent to | |
401 | ask for the tag specifically. Some helpers may be able to | |
402 | use this option to avoid a second network connection. | |
403 | ||
ae4efe19 SP |
404 | 'option dry-run' \{'true'|'false'\}: |
405 | If true, pretend the operation completed successfully, | |
406 | but don't actually change any repository data. For most | |
407 | helpers this only applies to the 'push', if supported. | |
408 | ||
fa8c097c | 409 | 'option servpath <c-style-quoted-path>':: |
d43427d3 RR |
410 | Sets service path (--upload-pack, --receive-pack etc.) for |
411 | next connect. Remote helper may support this option, but | |
412 | must not rely on this option being set before | |
fa8c097c IL |
413 | connect request occurs. |
414 | ||
b6c8d2d6 RR |
415 | SEE ALSO |
416 | -------- | |
417 | linkgit:git-remote[1] | |
418 | ||
9609dc9d MM |
419 | linkgit:git-remote-testgit[1] |
420 | ||
6eb996b5 DB |
421 | GIT |
422 | --- | |
423 | Part of the linkgit:git[1] suite |