http://<host>:<port>/<path>?<searchpart>
-Within this documentation the placeholder $GIT_URL will stand for
+Within this documentation the placeholder `$GIT_URL` will stand for
the http:// repository URL entered by the end-user.
-Servers SHOULD handle all requests to locations matching $GIT_URL, as
+Servers SHOULD handle all requests to locations matching `$GIT_URL`, as
both the "smart" and "dumb" HTTP protocols used by Git operate
by appending additional path components onto the end of the user
-supplied $GIT_URL string.
+supplied `$GIT_URL` string.
An example of a dumb client requesting for a loose object:
$GIT_URL: http://example.com/git/repo.git/path/submodule.git
URL request: http://example.com/git/repo.git/path/submodule.git/info/refs
-Clients MUST strip a trailing '/', if present, from the user supplied
-$GIT_URL string to prevent empty path tokens ('//') from appearing
+Clients MUST strip a trailing `/`, if present, from the user supplied
+`$GIT_URL` string to prevent empty path tokens (`//`) from appearing
in any URL sent to a server. Compatible clients MUST expand
-'$GIT_URL/info/refs' as 'foo/info/refs' and not 'foo//info/refs'.
+`$GIT_URL/info/refs` as `foo/info/refs` and not `foo//info/refs`.
Authentication
server administrators MAY use directory based permissions within
their HTTP server to control repository access.
-Clients SHOULD support Basic authentication as described by RFC 2616.
+Clients SHOULD support Basic authentication as described by RFC 2617.
Servers SHOULD support Basic authentication by relying upon the
HTTP server placed in front of the Git server software.
by both client and server. This includes (but is not necessarily
limited to):
-If there is no repository at $GIT_URL, or the resource pointed to by a
-location matching $GIT_URL does not exist, the server MUST NOT respond
-with '200 OK' response. A server SHOULD respond with
-'404 Not Found', '410 Gone', or any other suitable HTTP status code
+If there is no repository at `$GIT_URL`, or the resource pointed to by a
+location matching `$GIT_URL` does not exist, the server MUST NOT respond
+with `200 OK` response. A server SHOULD respond with
+`404 Not Found`, `410 Gone`, or any other suitable HTTP status code
which does not imply the resource exists as requested.
-If there is a repository at $GIT_URL, but access is not currently
-permitted, the server MUST respond with the '403 Forbidden' HTTP
+If there is a repository at `$GIT_URL`, but access is not currently
+permitted, the server MUST respond with the `403 Forbidden` HTTP
status code.
Servers SHOULD support both HTTP 1.0 and HTTP 1.1.
Clients MAY revalidate cached entities by including If-Modified-Since
and/or If-None-Match request headers.
-Servers MAY return '304 Not Modified' if the relevant headers appear
+Servers MAY return `304 Not Modified` if the relevant headers appear
in the request and the entity has not changed. Clients MUST treat
-'304 Not Modified' identical to '200 OK' by reusing the cached entity.
+`304 Not Modified` identical to `200 OK` by reusing the cached entity.
Clients MAY reuse a cached entity without revalidation if the
Cache-Control and/or Expires header permits caching. Clients and
references by making a request for the special info/refs file of
the repository.
-Dumb HTTP clients MUST make a GET request to $GIT_URL/info/refs,
+Dumb HTTP clients MUST make a `GET` request to `$GIT_URL/info/refs`,
without any search/query parameters.
C: GET $GIT_URL/info/refs HTTP/1.0
S: a3c2e2402b99163d1d59756e5f207ae21cccba4c refs/tags/v1.0^{}
The Content-Type of the returned info/refs entity SHOULD be
-"text/plain; charset=utf-8", but MAY be any content type.
+`text/plain; charset=utf-8`, but MAY be any content type.
Clients MUST NOT attempt to validate the returned Content-Type.
Dumb servers MUST NOT return a return type starting with
-"application/x-git-".
+`application/x-git-`.
Cache-Control headers MAY be returned to disable caching of the
returned entity.
When examining the response clients SHOULD only examine the HTTP
-status code. Valid responses are '200 OK', or '304 Not Modified'.
+status code. Valid responses are `200 OK`, or `304 Not Modified`.
The returned content is a UNIX formatted text file describing
each ref and its known value. The file SHOULD be sorted by name
according to the C locale ordering. The file SHOULD NOT include
-the default ref named 'HEAD'.
+the default ref named `HEAD`.
info_refs = *( ref_record )
ref_record = any_ref / peeled_ref
a parameterized request for the info/refs file of the repository.
The request MUST contain exactly one query parameter,
-'service=$servicename', where $servicename MUST be the service
+`service=$servicename`, where `$servicename` MUST be the service
name the client wishes to contact to complete the operation.
The request MUST NOT contain additional query parameters.
C: GET $GIT_URL/info/refs?service=git-upload-pack HTTP/1.0
- dumb server reply:
+dumb server reply:
+
S: 200 OK
S:
S: 95dcfa3633004da0049d3d0fa03f80589cbcaf31 refs/heads/maint
S: 2cb58b79488a98d2721cea644875a8dd0026b115 refs/tags/v1.0
S: a3c2e2402b99163d1d59756e5f207ae21cccba4c refs/tags/v1.0^{}
- smart server reply:
+smart server reply:
+
S: 200 OK
S: Content-Type: application/x-git-upload-pack-advertisement
S: Cache-Control: no-cache
^^^^^^^^^^^^^^^^^^^^^
If the server does not recognize the requested service name, or the
requested service name has been disabled by the server administrator,
-the server MUST respond with the '403 Forbidden' HTTP status code.
+the server MUST respond with the `403 Forbidden` HTTP status code.
Otherwise, smart servers MUST respond with the smart server reply
format for the requested service name.
Cache-Control headers SHOULD be used to disable caching of the
returned entity.
-The Content-Type MUST be 'application/x-$servicename-advertisement'.
+The Content-Type MUST be `application/x-$servicename-advertisement`.
Clients SHOULD fall back to the dumb protocol if another content
type is returned. When falling back to the dumb protocol clients
-SHOULD NOT make an additional request to $GIT_URL/info/refs, but
+SHOULD NOT make an additional request to `$GIT_URL/info/refs`, but
instead SHOULD use the response already in hand. Clients MUST NOT
continue if they do not support the dumb protocol.
-Clients MUST validate the status code is either '200 OK' or
-'304 Not Modified'.
+Clients MUST validate the status code is either `200 OK` or
+`304 Not Modified`.
Clients MUST validate the first five bytes of the response entity
-matches the regex "^[0-9a-f]{4}#". If this test fails, clients
+matches the regex `^[0-9a-f]{4}#`. If this test fails, clients
MUST NOT continue.
Clients MUST parse the entire response as a sequence of pkt-line
records.
-Clients MUST verify the first pkt-line is "# service=$servicename".
+Clients MUST verify the first pkt-line is `# service=$servicename`.
Servers MUST set $servicename to be the request parameter value.
Servers SHOULD include an LF at the end of this line.
Clients MUST ignore an LF at the end of the line.
-Servers MUST terminate the response with the magic "0000" end
+Servers MUST terminate the response with the magic `0000` end
pkt-line marker.
The returned response is a pkt-line stream describing each ref and
its known value. The stream SHOULD be sorted by name according to
the C locale ordering. The stream SHOULD include the default ref
-named 'HEAD' as the first ref. The stream MUST include capability
+named `HEAD` as the first ref. The stream MUST include capability
declarations behind a NUL on the first ref.
smart_reply = PKT-LINE("# service=$servicename" LF)
peeled_ref = PKT-LINE(obj-id SP name LF)
PKT-LINE(obj-id SP name "^{}" LF
+
Smart Service git-upload-pack
------------------------------
-This service reads from the repository pointed to by $GIT_URL.
+This service reads from the repository pointed to by `$GIT_URL`.
Clients MUST first perform ref discovery with
-'$GIT_URL/info/refs?service=git-upload-pack'.
+`$GIT_URL/info/refs?service=git-upload-pack`.
C: POST $GIT_URL/git-upload-pack HTTP/1.0
C: Content-Type: application/x-git-upload-pack-request
Servers SHOULD support all capabilities defined here.
-Clients MUST send at least one 'want' command in the request body.
-Clients MUST NOT reference an id in a 'want' command which did not
+Clients MUST send at least one "want" command in the request body.
+Clients MUST NOT reference an id in a "want" command which did not
appear in the response obtained through ref discovery unless the
-server advertises capability "allow-tip-sha1-in-want".
+server advertises capability `allow-tip-sha1-in-want`.
compute_request = want_list
have_list
have_list = *PKT-LINE("have" SP id LF)
TODO: Document this further.
-TODO: Don't use uppercase for variable names below.
The Negotiation Algorithm
~~~~~~~~~~~~~~~~~~~~~~~~~
The computation to select the minimal pack proceeds as follows
-(c = client, s = server):
+(C = client, S = server):
+
+'init step:'
+
+C: Use ref discovery to obtain the advertised refs.
+
+C: Place any object seen into set `advertised`.
- init step:
- (c) Use ref discovery to obtain the advertised refs.
- (c) Place any object seen into set ADVERTISED.
+C: Build an empty set, `common`, to hold the objects that are later
+ determined to be on both ends.
- (c) Build an empty set, COMMON, to hold the objects that are later
- determined to be on both ends.
- (c) Build a set, WANT, of the objects from ADVERTISED the client
- wants to fetch, based on what it saw during ref discovery.
+C: Build a set, `want`, of the objects from `advertised` the client
+ wants to fetch, based on what it saw during ref discovery.
- (c) Start a queue, C_PENDING, ordered by commit time (popping newest
- first). Add all client refs. When a commit is popped from
- the queue its parents SHOULD be automatically inserted back.
- Commits MUST only enter the queue once.
+C: Start a queue, `c_pending`, ordered by commit time (popping newest
+ first). Add all client refs. When a commit is popped from
+ the queue its parents SHOULD be automatically inserted back.
+ Commits MUST only enter the queue once.
- one compute step:
- (c) Send one $GIT_URL/git-upload-pack request:
+'one compute step:'
- C: 0032want <WANT #1>...............................
- C: 0032want <WANT #2>...............................
+C: Send one `$GIT_URL/git-upload-pack` request:
+
+ C: 0032want <want #1>...............................
+ C: 0032want <want #2>...............................
....
- C: 0032have <COMMON #1>.............................
- C: 0032have <COMMON #2>.............................
+ C: 0032have <common #1>.............................
+ C: 0032have <common #2>.............................
....
- C: 0032have <HAVE #1>...............................
- C: 0032have <HAVE #2>...............................
+ C: 0032have <have #1>...............................
+ C: 0032have <have #2>...............................
....
C: 0000
- The stream is organized into "commands", with each command
- appearing by itself in a pkt-line. Within a command line
- the text leading up to the first space is the command name,
- and the remainder of the line to the first LF is the value.
- Command lines are terminated with an LF as the last byte of
- the pkt-line value.
+The stream is organized into "commands", with each command
+appearing by itself in a pkt-line. Within a command line,
+the text leading up to the first space is the command name,
+and the remainder of the line to the first LF is the value.
+Command lines are terminated with an LF as the last byte of
+the pkt-line value.
- Commands MUST appear in the following order, if they appear
- at all in the request stream:
+Commands MUST appear in the following order, if they appear
+at all in the request stream:
- * want
- * have
+* "want"
+* "have"
- The stream is terminated by a pkt-line flush ("0000").
+The stream is terminated by a pkt-line flush (`0000`).
- A single "want" or "have" command MUST have one hex formatted
- SHA-1 as its value. Multiple SHA-1s MUST be sent by sending
- multiple commands.
+A single "want" or "have" command MUST have one hex formatted
+SHA-1 as its value. Multiple SHA-1s MUST be sent by sending
+multiple commands.
- The HAVE list is created by popping the first 32 commits
- from C_PENDING. Less can be supplied if C_PENDING empties.
+The `have` list is created by popping the first 32 commits
+from `c_pending`. Less can be supplied if `c_pending` empties.
- If the client has sent 256 HAVE commits and has not yet
- received one of those back from S_COMMON, or the client has
- emptied C_PENDING it SHOULD include a "done" command to let
- the server know it won't proceed:
+If the client has sent 256 "have" commits and has not yet
+received one of those back from `s_common`, or the client has
+emptied `c_pending` it SHOULD include a "done" command to let
+the server know it won't proceed:
C: 0009done
- (s) Parse the git-upload-pack request:
-
- Verify all objects in WANT are directly reachable from refs.
-
- The server MAY walk backwards through history or through
- the reflog to permit slightly stale requests.
+S: Parse the git-upload-pack request:
- If no WANT objects are received, send an error:
+Verify all objects in `want` are directly reachable from refs.
-TODO: Define error if no want lines are requested.
+The server MAY walk backwards through history or through
+the reflog to permit slightly stale requests.
- If any WANT object is not reachable, send an error:
+If no "want" objects are received, send an error:
+TODO: Define error if no "want" lines are requested.
-TODO: Define error if an invalid want is requested.
+If any "want" object is not reachable, send an error:
+TODO: Define error if an invalid "want" is requested.
- Create an empty list, S_COMMON.
+Create an empty list, `s_common`.
- If 'have' was sent:
+If "have" was sent:
- Loop through the objects in the order supplied by the client.
- For each object, if the server has the object reachable from
- a ref, add it to S_COMMON. If a commit is added to S_COMMON,
- do not add any ancestors, even if they also appear in HAVE.
+Loop through the objects in the order supplied by the client.
- (s) Send the git-upload-pack response:
+For each object, if the server has the object reachable from
+a ref, add it to `s_common`. If a commit is added to `s_common`,
+do not add any ancestors, even if they also appear in `have`.
- If the server has found a closed set of objects to pack or the
- request ends with "done", it replies with the pack.
+S: Send the git-upload-pack response:
+If the server has found a closed set of objects to pack or the
+request ends with "done", it replies with the pack.
TODO: Document the pack based response
- S: PACK...
- The returned stream is the side-band-64k protocol supported
- by the git-upload-pack service, and the pack is embedded into
- stream 1. Progress messages from the server side MAY appear
- in stream 2.
+ S: PACK...
- Here a "closed set of objects" is defined to have at least
- one path from every WANT to at least one COMMON object.
+The returned stream is the side-band-64k protocol supported
+by the git-upload-pack service, and the pack is embedded into
+stream 1. Progress messages from the server side MAY appear
+in stream 2.
- If the server needs more information, it replies with a
- status continue response:
+Here a "closed set of objects" is defined to have at least
+one path from every "want" to at least one "common" object.
+If the server needs more information, it replies with a
+status continue response:
TODO: Document the non-pack response
- (c) Parse the upload-pack response:
-
-TODO: Document parsing response
+C: Parse the upload-pack response:
+ TODO: Document parsing response
- Do another compute step.
+'Do another compute step.'
Smart Service git-receive-pack
------------------------------
-This service reads from the repository pointed to by $GIT_URL.
+This service reads from the repository pointed to by `$GIT_URL`.
Clients MUST first perform ref discovery with
-'$GIT_URL/info/refs?service=git-receive-pack'.
+`$GIT_URL/info/refs?service=git-receive-pack`.
C: POST $GIT_URL/git-receive-pack HTTP/1.0
C: Content-Type: application/x-git-receive-pack-request
References
----------
-link:http://www.ietf.org/rfc/rfc1738.txt[RFC 1738: Uniform Resource Locators (URL)]
-link:http://www.ietf.org/rfc/rfc2616.txt[RFC 2616: Hypertext Transfer Protocol -- HTTP/1.1]
+http://www.ietf.org/rfc/rfc1738.txt[RFC 1738: Uniform Resource Locators (URL)]
+http://www.ietf.org/rfc/rfc2616.txt[RFC 2616: Hypertext Transfer Protocol -- HTTP/1.1]
link:technical/pack-protocol.html
link:technical/protocol-capabilities.html