The file:// transport runs the 'upload-pack' or 'receive-pack'
process locally and communicates with it over a pipe.
+Extra Parameters
+----------------
+
+The protocol provides a mechanism in which clients can send additional
+information in its first message to the server. These are called "Extra
+Parameters", and are supported by the Git, SSH, and HTTP protocols.
+
+Each Extra Parameter takes the form of `<key>=<value>` or `<key>`.
+
+Servers that receive any such Extra Parameters MUST ignore all
+unrecognized keys. Currently, the only Extra Parameter recognized is
+"version" with a value of '1' or '2'. See protocol-v2.txt for more
+information on protocol version 2.
+
Git Transport
-------------
on the wire using the pkt-line format, followed by a NUL byte and a
hostname parameter, terminated by a NUL byte.
- 0032git-upload-pack /project.git\0host=myserver.com\0
+ 0033git-upload-pack /project.git\0host=myserver.com\0
+
+The transport may send Extra Parameters by adding an additional NUL
+byte, and then adding one or more NUL-terminated strings:
+
+ 003egit-upload-pack /project.git\0host=myserver.com\0\0version=1\0
--
- git-proto-request = request-command SP pathname NUL [ host-parameter NUL ]
+ git-proto-request = request-command SP pathname NUL
+ [ host-parameter NUL ] [ NUL extra-parameters ]
request-command = "git-upload-pack" / "git-receive-pack" /
"git-upload-archive" ; case sensitive
pathname = *( %x01-ff ) ; exclude NUL
host-parameter = "host=" hostname [ ":" port ]
+ extra-parameters = 1*extra-parameter
+ extra-parameter = 1*( %x01-ff ) NUL
--
-Only host-parameter is allowed in the git-proto-request. Clients
-MUST NOT attempt to send additional parameters. It is used for the
+host-parameter is used for the
git-daemon name based virtual hosting. See --interpolated-path
option to git daemon, with the %H/%CH format characters.
v
ssh user@example.com "git-upload-pack '~alice/project.git'"
+Depending on the value of the `protocol.version` configuration variable,
+Git may attempt to send Extra Parameters as a colon-separated string in
+the GIT_PROTOCOL environment variable. This is done only if
+the `ssh.variant` configuration variable indicates that the ssh command
+supports passing environment variables as an argument.
+
A few things to remember here:
- The "command name" is spelled with dash (e.g. git-upload-pack), but
-------------------
When the client initially connects the server will immediately respond
-with a listing of each reference it has (all branches and tags) along
+with a version number (if "version=1" is sent as an Extra Parameter),
+and a listing of each reference it has (all branches and tags) along
with the object name that each reference currently points to.
- $ echo -e -n "0039git-upload-pack /schacon/gitbook.git\0host=example.com\0" |
+ $ echo -e -n "0044git-upload-pack /schacon/gitbook.git\0host=example.com\0\0version=1\0" |
nc -v example.com 9418
+ 000aversion 1
00887217a7c7e582c46cec22a130adf4b9d7d950fba0 HEAD\0multi_ack thin-pack
side-band side-band-64k ofs-delta shallow no-progress include-tag
00441d3fcd5ced445d1abc402225c0b8a1299641f497 refs/heads/integration
MUST peel the ref if it's an annotated tag.
----
- advertised-refs = (no-refs / list-of-refs)
+ advertised-refs = *1("version 1")
+ (no-refs / list-of-refs)
*shallow
flush-pkt
terminate the connection by sending a flush-pkt, telling the server it can
now gracefully terminate, and disconnect, when it does not need any pack
data. This can happen with the ls-remote command, and also can happen when
-the client already is up-to-date.
+the client already is up to date.
Otherwise, it enters the negotiation phase, where the client and
server determine what the minimal packfile necessary for transport is,
shallow-line = PKT-LINE("shallow" SP obj-id)
- depth-request = PKT-LINE("deepen" SP depth)
+ depth-request = PKT-LINE("deepen" SP depth) /
+ PKT-LINE("deepen-since" SP timestamp) /
+ PKT-LINE("deepen-not" SP ref)
first-want = PKT-LINE("want" SP obj-id SP capability-list)
additional-want = PKT-LINE("want" SP obj-id)
multi_ack_detailed is enabled. The server always sends NAK after 'done'
if there is no common base found.
+Instead of 'ACK' or 'NAK', the server may send an error message (for
+example, if it does not recognize an object in a 'want' line received
+from the client).
+
Then the server will start sending its packfile data.
----
- server-response = *ack_multi ack / nak
+ server-response = *ack_multi ack / nak / error-line
ack_multi = PKT-LINE("ACK" SP obj-id ack_status)
ack_status = "continue" / "common" / "ready"
ack = PKT-LINE("ACK" SP obj-id)
nak = PKT-LINE("NAK")
+ error-line = PKT-LINE("ERR" SP explanation-text)
----
A simple clone may look like this (with no 'have' lines):
the server, the obj-id the client would like to update it to and the name
of the reference.
-This list is followed by a flush-pkt. Then the push options are transmitted
-one per packet followed by another flush-pkt. After that the packfile that
-should contain all the objects that the server will need to complete the new
-references will be sent.
+This list is followed by a flush-pkt.
----
- update-request = *shallow ( command-list | push-cert ) [packfile]
+ update-requests = *shallow ( command-list | push-cert )
shallow = PKT-LINE("shallow" SP obj-id)
PKT-LINE("pusher" SP ident LF)
PKT-LINE("pushee" SP url LF)
PKT-LINE("nonce" SP nonce LF)
+ *PKT-LINE("push-option" SP push-option LF)
PKT-LINE(LF)
*PKT-LINE(command LF)
*PKT-LINE(gpg-signature-lines LF)
PKT-LINE("push-cert-end" LF)
- packfile = "PACK" 28*(OCTET)
+ push-option = 1*( VCHAR | SP )
+----
+
+If the server has advertised the 'push-options' capability and the client has
+specified 'push-options' as part of the capability list above, the client then
+sends its push options followed by a flush-pkt.
+
+----
+ push-options = *PKT-LINE(push-option) flush-pkt
+----
+
+For backwards compatibility with older Git servers, if the client sends a push
+cert and push options, it MUST send its push options both embedded within the
+push cert and after the push cert. (Note that the push options within the cert
+are prefixed, but the push options after the cert are not.) Both these lists
+MUST be the same, modulo the prefix.
+
+After that the packfile that
+should contain all the objects that the server will need to complete the new
+references will be sent.
+
+----
+ packfile = "PACK" 28*(OCTET)
----
If the receiving end does not support delete-refs, the sending end MUST