wireprotov2: change command response protocol to include a leading map
The error handling mechanism for the new wire protocol isn't very
well-defined. This commit takes us a step in the right direction
by introducing a leading CBOR map for command responses. This map
will contain an overall result of the command.
Currently, the map indicates whether the command was overall
successful or if an error occurred. And if an error occurred, that
error is present in the map.
There is still a dedicated error frame. My intent is to use that
for protocol-level errors and for errors that are encountered after
the initial response frame has been sent. This will be clarified in a
later commit.
Differential Revision: https://phab.mercurial-scm.org/D3385
$ . $TESTDIR/wireprotohelpers.sh
$ hg init server
$ enablehttpv2 server
$ cd server
$ cat >> .hg/hgrc << EOF
> [web]
> push_ssl = false
> allow-push = *
> EOF
$ hg debugdrawdag << EOF
> C D
> |/
> B
> |
> A
> EOF
$ hg serve -p $HGPORT -d --pid-file hg.pid -E error.log
$ cat hg.pid > $DAEMON_PIDS
lookup for known node works
$ sendhttpv2peer << EOF
> command lookup
> key 426bada5c67598ca65036d57d9e4b64b0c1ce7a0
> EOF
creating http peer for wire protocol version 2
sending lookup command
s> *\r\n (glob)
s> Accept-Encoding: identity\r\n
s> accept: application/mercurial-exp-framing-0005\r\n
s> content-type: application/mercurial-exp-framing-0005\r\n
s> content-length: 73\r\n
s> host: $LOCALIP:$HGPORT\r\n (glob)
s> user-agent: Mercurial debugwireproto\r\n
s> \r\n
s> A\x00\x00\x01\x00\x01\x01\x11\xa2Dargs\xa1CkeyX(426bada5c67598ca65036d57d9e4b64b0c1ce7a0DnameFlookup
s> makefile('rb', None)
s> HTTP/1.1 200 OK\r\n
s> Server: testing stub value\r\n
s> Date: $HTTP_DATE$\r\n
s> Content-Type: application/mercurial-exp-framing-0005\r\n
s> Transfer-Encoding: chunked\r\n
s> \r\n
s> 28\r\n
s> \x00\x00\x01\x00\x02\x012
s> \xa1FstatusBokTBk\xad\xa5\xc6u\x98\xcae\x03mW\xd9\xe4\xb6K\x0c\x1c\xe7\xa0
s> \r\n
received frame(size=32; request=1; stream=2; streamflags=stream-begin; type=command-response; flags=eos)
s> 0\r\n
s> \r\n
response: b'Bk\xad\xa5\xc6u\x98\xcae\x03mW\xd9\xe4\xb6K\x0c\x1c\xe7\xa0'
$ cat error.log