wireprotov2: move response handling out of httppeer
And fix some bugs while we're here.
The code for processing response data from the unified framing
protocol is mostly peer agnostic. The peer-specific bits are the
configuration of the client reactor and how I/O is performed. I
initially implemented things in httppeer for expediency.
This commit establishes a module for holding the peer API level
code for the framing based protocol. Inside this module we have
a class to help coordinate higher-level activities, such as managing
response object.
The client handler bits could be rolled into clientreactor. However,
I want clientreactor to be sans I/O and I want it to only be
concerned with protocol-level details, not higher-level concepts
like how protocol events are converted into peer API concepts. I
want clientreactor to receive a frame and then tell the caller what
should probably be done about it. If we start putting things like
future resolution into clientreactor, we'll constrain how the protocol
can be used (e.g. by requiring futures).
The new code is loosely based on what was in httppeer before. I
changed things a bit around response handling. We now buffer the
entire response "body" and then handle it as one atomic unit. This
fixed a bug around decoding CBOR data that spanned multiple frames.
I also fixed an off-by-one bug where we failed to read a single byte
CBOR value at the end of the stream. That's why tests have changed.
The new state of httppeer is much cleaner. It is largely agnostic
about framing protocol implementation details. That's how it should
be: the framing protocol is designed to be largely transport
agnostic. We want peers merely putting bytes on the wire and telling
the framing protocol where to read response data from.
There's still a bit of work to be done here, especially for
representing responses. But at least we're a step closer to having a
higher-level peer interface that can be plugged into the SSH peer
someday.
I initially added this class to wireprotoframing. However, we'll
eventually need version 2 specific functions to convert CBOR responses
into data structures expected by the code calling commands. This
needs to live somewhere. Since that code would be shared across peers,
we need a common module. We have wireprotov1peer for the equivalent
version 1 code. So I decided to establish wireprotov2peer.
Differential Revision: https://phab.mercurial-scm.org/D3379
$ . $TESTDIR/wireprotohelpers.sh
$ enabledummycommands
$ hg init server
$ cat > server/.hg/hgrc << EOF
> [experimental]
> web.apiserver = true
> EOF
$ hg -R server serve -p $HGPORT -d --pid-file hg.pid
$ cat hg.pid > $DAEMON_PIDS
HTTP v2 protocol not enabled by default
$ sendhttpraw << EOF
> httprequest GET api/$HTTPV2
> user-agent: test
> EOF
using raw connection to peer
s> GET /api/exp-http-v2-0001 HTTP/1.1\r\n
s> Accept-Encoding: identity\r\n
s> user-agent: test\r\n
s> host: $LOCALIP:$HGPORT\r\n (glob)
s> \r\n
s> makefile('rb', None)
s> HTTP/1.1 404 Not Found\r\n
s> Server: testing stub value\r\n
s> Date: $HTTP_DATE$\r\n
s> Content-Type: text/plain\r\n
s> Content-Length: 33\r\n
s> \r\n
s> API exp-http-v2-0001 not enabled\n
Restart server with support for HTTP v2 API
$ killdaemons.py
$ enablehttpv2 server
$ hg -R server serve -p $HGPORT -d --pid-file hg.pid
$ cat hg.pid > $DAEMON_PIDS
Request to unknown command yields 404
$ sendhttpraw << EOF
> httprequest POST api/$HTTPV2/ro/badcommand
> user-agent: test
> EOF
using raw connection to peer
s> POST /api/exp-http-v2-0001/ro/badcommand HTTP/1.1\r\n
s> Accept-Encoding: identity\r\n
s> user-agent: test\r\n
s> host: $LOCALIP:$HGPORT\r\n (glob)
s> \r\n
s> makefile('rb', None)
s> HTTP/1.1 404 Not Found\r\n
s> Server: testing stub value\r\n
s> Date: $HTTP_DATE$\r\n
s> Content-Type: text/plain\r\n
s> Content-Length: 42\r\n
s> \r\n
s> unknown wire protocol command: badcommand\n
GET to read-only command yields a 405
$ sendhttpraw << EOF
> httprequest GET api/$HTTPV2/ro/customreadonly
> user-agent: test
> EOF
using raw connection to peer
s> GET /api/exp-http-v2-0001/ro/customreadonly HTTP/1.1\r\n
s> Accept-Encoding: identity\r\n
s> user-agent: test\r\n
s> host: $LOCALIP:$HGPORT\r\n (glob)
s> \r\n
s> makefile('rb', None)
s> HTTP/1.1 405 Method Not Allowed\r\n
s> Server: testing stub value\r\n
s> Date: $HTTP_DATE$\r\n
s> Allow: POST\r\n
s> Content-Length: 30\r\n
s> \r\n
s> commands require POST requests
Missing Accept header results in 406
$ sendhttpraw << EOF
> httprequest POST api/$HTTPV2/ro/customreadonly
> user-agent: test
> EOF
using raw connection to peer
s> POST /api/exp-http-v2-0001/ro/customreadonly HTTP/1.1\r\n
s> Accept-Encoding: identity\r\n
s> user-agent: test\r\n
s> host: $LOCALIP:$HGPORT\r\n (glob)
s> \r\n
s> makefile('rb', None)
s> HTTP/1.1 406 Not Acceptable\r\n
s> Server: testing stub value\r\n
s> Date: $HTTP_DATE$\r\n
s> Content-Type: text/plain\r\n
s> Content-Length: 85\r\n
s> \r\n
s> client MUST specify Accept header with value: application/mercurial-exp-framing-0003\n
Bad Accept header results in 406
$ sendhttpraw << EOF
> httprequest POST api/$HTTPV2/ro/customreadonly
> accept: invalid
> user-agent: test
> EOF
using raw connection to peer
s> POST /api/exp-http-v2-0001/ro/customreadonly HTTP/1.1\r\n
s> Accept-Encoding: identity\r\n
s> accept: invalid\r\n
s> user-agent: test\r\n
s> host: $LOCALIP:$HGPORT\r\n (glob)
s> \r\n
s> makefile('rb', None)
s> HTTP/1.1 406 Not Acceptable\r\n
s> Server: testing stub value\r\n
s> Date: $HTTP_DATE$\r\n
s> Content-Type: text/plain\r\n
s> Content-Length: 85\r\n
s> \r\n
s> client MUST specify Accept header with value: application/mercurial-exp-framing-0003\n
Bad Content-Type header results in 415
$ sendhttpraw << EOF
> httprequest POST api/$HTTPV2/ro/customreadonly
> accept: $MEDIATYPE
> user-agent: test
> content-type: badmedia
> EOF
using raw connection to peer
s> POST /api/exp-http-v2-0001/ro/customreadonly HTTP/1.1\r\n
s> Accept-Encoding: identity\r\n
s> accept: application/mercurial-exp-framing-0003\r\n
s> content-type: badmedia\r\n
s> user-agent: test\r\n
s> host: $LOCALIP:$HGPORT\r\n (glob)
s> \r\n
s> makefile('rb', None)
s> HTTP/1.1 415 Unsupported Media Type\r\n
s> Server: testing stub value\r\n
s> Date: $HTTP_DATE$\r\n
s> Content-Type: text/plain\r\n
s> Content-Length: 88\r\n
s> \r\n
s> client MUST send Content-Type header with value: application/mercurial-exp-framing-0003\n
Request to read-only command works out of the box
$ sendhttpraw << EOF
> httprequest POST api/$HTTPV2/ro/customreadonly
> accept: $MEDIATYPE
> content-type: $MEDIATYPE
> user-agent: test
> frame 1 1 stream-begin command-request new cbor:{b'name': b'customreadonly'}
> EOF
using raw connection to peer
s> POST /api/exp-http-v2-0001/ro/customreadonly HTTP/1.1\r\n
s> Accept-Encoding: identity\r\n
s> *\r\n (glob)
s> content-type: application/mercurial-exp-framing-0003\r\n
s> user-agent: test\r\n
s> content-length: 29\r\n
s> host: $LOCALIP:$HGPORT\r\n (glob)
s> \r\n
s> \x15\x00\x00\x01\x00\x01\x01\x11\xa1DnameNcustomreadonly
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-0003\r\n
s> Transfer-Encoding: chunked\r\n
s> \r\n
s> 25\r\n
s> \x1d\x00\x00\x01\x00\x02\x01Bcustomreadonly bytes response
s> \r\n
s> 0\r\n
s> \r\n
$ sendhttpv2peer << EOF
> command customreadonly
> EOF
creating http peer for wire protocol version 2
sending customreadonly command
s> POST /api/exp-http-v2-0001/ro/customreadonly HTTP/1.1\r\n
s> Accept-Encoding: identity\r\n
s> accept: application/mercurial-exp-framing-0003\r\n
s> content-type: application/mercurial-exp-framing-0003\r\n
s> content-length: 29\r\n
s> host: $LOCALIP:$HGPORT\r\n (glob)
s> user-agent: Mercurial debugwireproto\r\n
s> \r\n
s> \x15\x00\x00\x01\x00\x01\x01\x11\xa1DnameNcustomreadonly
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-0003\r\n
s> Transfer-Encoding: chunked\r\n
s> \r\n
s> 25\r\n
s> \x1d\x00\x00\x01\x00\x02\x01B
s> customreadonly bytes response
s> \r\n
received frame(size=29; request=1; stream=2; streamflags=stream-begin; type=bytes-response; flags=eos)
s> 0\r\n
s> \r\n
response: [b'customreadonly bytes response']
Request to read-write command fails because server is read-only by default
GET to read-write request yields 405
$ sendhttpraw << EOF
> httprequest GET api/$HTTPV2/rw/customreadonly
> user-agent: test
> EOF
using raw connection to peer
s> GET /api/exp-http-v2-0001/rw/customreadonly HTTP/1.1\r\n
s> Accept-Encoding: identity\r\n
s> user-agent: test\r\n
s> host: $LOCALIP:$HGPORT\r\n (glob)
s> \r\n
s> makefile('rb', None)
s> HTTP/1.1 405 Method Not Allowed\r\n
s> Server: testing stub value\r\n
s> Date: $HTTP_DATE$\r\n
s> Allow: POST\r\n
s> Content-Length: 30\r\n
s> \r\n
s> commands require POST requests
Even for unknown commands
$ sendhttpraw << EOF
> httprequest GET api/$HTTPV2/rw/badcommand
> user-agent: test
> EOF
using raw connection to peer
s> GET /api/exp-http-v2-0001/rw/badcommand HTTP/1.1\r\n
s> Accept-Encoding: identity\r\n
s> user-agent: test\r\n
s> host: $LOCALIP:$HGPORT\r\n (glob)
s> \r\n
s> makefile('rb', None)
s> HTTP/1.1 405 Method Not Allowed\r\n
s> Server: testing stub value\r\n
s> Date: $HTTP_DATE$\r\n
s> Allow: POST\r\n
s> Content-Length: 30\r\n
s> \r\n
s> commands require POST requests
SSL required by default
$ sendhttpraw << EOF
> httprequest POST api/$HTTPV2/rw/customreadonly
> user-agent: test
> EOF
using raw connection to peer
s> POST /api/exp-http-v2-0001/rw/customreadonly HTTP/1.1\r\n
s> Accept-Encoding: identity\r\n
s> user-agent: test\r\n
s> host: $LOCALIP:$HGPORT\r\n (glob)
s> \r\n
s> makefile('rb', None)
s> HTTP/1.1 403 ssl required\r\n
s> Server: testing stub value\r\n
s> Date: $HTTP_DATE$\r\n
s> Content-Length: 17\r\n
s> \r\n
s> permission denied
Restart server to allow non-ssl read-write operations
$ killdaemons.py
$ cat > server/.hg/hgrc << EOF
> [experimental]
> web.apiserver = true
> web.api.http-v2 = true
> [web]
> push_ssl = false
> allow-push = *
> EOF
$ hg -R server serve -p $HGPORT -d --pid-file hg.pid -E error.log
$ cat hg.pid > $DAEMON_PIDS
Authorized request for valid read-write command works
$ sendhttpraw << EOF
> httprequest POST api/$HTTPV2/rw/customreadonly
> user-agent: test
> accept: $MEDIATYPE
> content-type: $MEDIATYPE
> frame 1 1 stream-begin command-request new cbor:{b'name': b'customreadonly'}
> EOF
using raw connection to peer
s> POST /api/exp-http-v2-0001/rw/customreadonly HTTP/1.1\r\n
s> Accept-Encoding: identity\r\n
s> accept: application/mercurial-exp-framing-0003\r\n
s> content-type: application/mercurial-exp-framing-0003\r\n
s> user-agent: test\r\n
s> content-length: 29\r\n
s> host: $LOCALIP:$HGPORT\r\n (glob)
s> \r\n
s> \x15\x00\x00\x01\x00\x01\x01\x11\xa1DnameNcustomreadonly
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-0003\r\n
s> Transfer-Encoding: chunked\r\n
s> \r\n
s> 25\r\n
s> \x1d\x00\x00\x01\x00\x02\x01Bcustomreadonly bytes response
s> \r\n
s> 0\r\n
s> \r\n
Authorized request for unknown command is rejected
$ sendhttpraw << EOF
> httprequest POST api/$HTTPV2/rw/badcommand
> user-agent: test
> accept: $MEDIATYPE
> EOF
using raw connection to peer
s> POST /api/exp-http-v2-0001/rw/badcommand HTTP/1.1\r\n
s> Accept-Encoding: identity\r\n
s> accept: application/mercurial-exp-framing-0003\r\n
s> user-agent: test\r\n
s> host: $LOCALIP:$HGPORT\r\n (glob)
s> \r\n
s> makefile('rb', None)
s> HTTP/1.1 404 Not Found\r\n
s> Server: testing stub value\r\n
s> Date: $HTTP_DATE$\r\n
s> Content-Type: text/plain\r\n
s> Content-Length: 42\r\n
s> \r\n
s> unknown wire protocol command: badcommand\n
debugreflect isn't enabled by default
$ sendhttpraw << EOF
> httprequest POST api/$HTTPV2/ro/debugreflect
> user-agent: test
> EOF
using raw connection to peer
s> POST /api/exp-http-v2-0001/ro/debugreflect HTTP/1.1\r\n
s> Accept-Encoding: identity\r\n
s> user-agent: test\r\n
s> host: $LOCALIP:$HGPORT\r\n (glob)
s> \r\n
s> makefile('rb', None)
s> HTTP/1.1 404 Not Found\r\n
s> Server: testing stub value\r\n
s> Date: $HTTP_DATE$\r\n
s> Content-Type: text/plain\r\n
s> Content-Length: 34\r\n
s> \r\n
s> debugreflect service not available
Restart server to get debugreflect endpoint
$ killdaemons.py
$ cat > server/.hg/hgrc << EOF
> [experimental]
> web.apiserver = true
> web.api.debugreflect = true
> web.api.http-v2 = true
> [web]
> push_ssl = false
> allow-push = *
> EOF
$ hg -R server serve -p $HGPORT -d --pid-file hg.pid -E error.log
$ cat hg.pid > $DAEMON_PIDS
Command frames can be reflected via debugreflect
$ sendhttpraw << EOF
> httprequest POST api/$HTTPV2/ro/debugreflect
> accept: $MEDIATYPE
> content-type: $MEDIATYPE
> user-agent: test
> frame 1 1 stream-begin command-request new cbor:{b'name': b'command1', b'args': {b'foo': b'val1', b'bar1': b'val'}}
> EOF
using raw connection to peer
s> POST /api/exp-http-v2-0001/ro/debugreflect HTTP/1.1\r\n
s> Accept-Encoding: identity\r\n
s> accept: application/mercurial-exp-framing-0003\r\n
s> content-type: application/mercurial-exp-framing-0003\r\n
s> user-agent: test\r\n
s> content-length: 47\r\n
s> host: $LOCALIP:$HGPORT\r\n (glob)
s> \r\n
s> \'\x00\x00\x01\x00\x01\x01\x11\xa2Dargs\xa2CfooDval1Dbar1CvalDnameHcommand1
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: text/plain\r\n
s> Content-Length: 205\r\n
s> \r\n
s> received: 1 1 1 \xa2Dargs\xa2CfooDval1Dbar1CvalDnameHcommand1\n
s> ["runcommand", {"args": {"bar1": "val", "foo": "val1"}, "command": "command1", "data": null, "requestid": 1}]\n
s> received: <no frame>\n
s> {"action": "noop"}
Multiple requests to regular command URL are not allowed
$ sendhttpraw << EOF
> httprequest POST api/$HTTPV2/ro/customreadonly
> accept: $MEDIATYPE
> content-type: $MEDIATYPE
> user-agent: test
> frame 1 1 stream-begin command-request new cbor:{b'name': b'customreadonly'}
> EOF
using raw connection to peer
s> POST /api/exp-http-v2-0001/ro/customreadonly HTTP/1.1\r\n
s> Accept-Encoding: identity\r\n
s> accept: application/mercurial-exp-framing-0003\r\n
s> content-type: application/mercurial-exp-framing-0003\r\n
s> user-agent: test\r\n
s> content-length: 29\r\n
s> host: $LOCALIP:$HGPORT\r\n (glob)
s> \r\n
s> \x15\x00\x00\x01\x00\x01\x01\x11\xa1DnameNcustomreadonly
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-0003\r\n
s> Transfer-Encoding: chunked\r\n
s> \r\n
s> 25\r\n
s> \x1d\x00\x00\x01\x00\x02\x01Bcustomreadonly bytes response
s> \r\n
s> 0\r\n
s> \r\n
Multiple requests to "multirequest" URL are allowed
$ sendhttpraw << EOF
> httprequest POST api/$HTTPV2/ro/multirequest
> accept: $MEDIATYPE
> content-type: $MEDIATYPE
> user-agent: test
> frame 1 1 stream-begin command-request new cbor:{b'name': b'customreadonly'}
> frame 3 1 0 command-request new cbor:{b'name': b'customreadonly'}
> EOF
using raw connection to peer
s> POST /api/exp-http-v2-0001/ro/multirequest HTTP/1.1\r\n
s> Accept-Encoding: identity\r\n
s> *\r\n (glob)
s> *\r\n (glob)
s> user-agent: test\r\n
s> content-length: 58\r\n
s> host: $LOCALIP:$HGPORT\r\n (glob)
s> \r\n
s> \x15\x00\x00\x01\x00\x01\x01\x11\xa1DnameNcustomreadonly\x15\x00\x00\x03\x00\x01\x00\x11\xa1DnameNcustomreadonly
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-0003\r\n
s> Transfer-Encoding: chunked\r\n
s> \r\n
s> 25\r\n
s> \x1d\x00\x00\x01\x00\x02\x01Bcustomreadonly bytes response
s> \r\n
s> 25\r\n
s> \x1d\x00\x00\x03\x00\x02\x00Bcustomreadonly bytes response
s> \r\n
s> 0\r\n
s> \r\n
Interleaved requests to "multirequest" are processed
$ sendhttpraw << EOF
> httprequest POST api/$HTTPV2/ro/multirequest
> accept: $MEDIATYPE
> content-type: $MEDIATYPE
> user-agent: test
> frame 1 1 stream-begin command-request new|more \xa2Dargs\xa1Inamespace
> frame 3 1 0 command-request new|more \xa2Dargs\xa1Inamespace
> frame 3 1 0 command-request continuation JnamespacesDnameHlistkeys
> frame 1 1 0 command-request continuation IbookmarksDnameHlistkeys
> EOF
using raw connection to peer
s> POST /api/exp-http-v2-0001/ro/multirequest HTTP/1.1\r\n
s> Accept-Encoding: identity\r\n
s> accept: application/mercurial-exp-framing-0003\r\n
s> content-type: application/mercurial-exp-framing-0003\r\n
s> user-agent: test\r\n
s> content-length: 115\r\n
s> host: $LOCALIP:$HGPORT\r\n (glob)
s> \r\n
s> \x11\x00\x00\x01\x00\x01\x01\x15\xa2Dargs\xa1Inamespace\x11\x00\x00\x03\x00\x01\x00\x15\xa2Dargs\xa1Inamespace\x19\x00\x00\x03\x00\x01\x00\x12JnamespacesDnameHlistkeys\x18\x00\x00\x01\x00\x01\x00\x12IbookmarksDnameHlistkeys
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-0003\r\n
s> Transfer-Encoding: chunked\r\n
s> \r\n
s> 28\r\n
s> \x00\x00\x03\x00\x02\x01F\xa3Fphases@Ibookmarks@Jnamespaces@
s> \r\n
s> 9\r\n
s> \x01\x00\x00\x01\x00\x02\x00F\xa0
s> \r\n
s> 0\r\n
s> \r\n
Restart server to disable read-write access
$ killdaemons.py
$ cat > server/.hg/hgrc << EOF
> [experimental]
> web.apiserver = true
> web.api.debugreflect = true
> web.api.http-v2 = true
> [web]
> push_ssl = false
> EOF
$ hg -R server serve -p $HGPORT -d --pid-file hg.pid -E error.log
$ cat hg.pid > $DAEMON_PIDS
Attempting to run a read-write command via multirequest on read-only URL is not allowed
$ sendhttpraw << EOF
> httprequest POST api/$HTTPV2/ro/multirequest
> accept: $MEDIATYPE
> content-type: $MEDIATYPE
> user-agent: test
> frame 1 1 stream-begin command-request new cbor:{b'name': b'pushkey'}
> EOF
using raw connection to peer
s> POST /api/exp-http-v2-0001/ro/multirequest HTTP/1.1\r\n
s> Accept-Encoding: identity\r\n
s> accept: application/mercurial-exp-framing-0003\r\n
s> content-type: application/mercurial-exp-framing-0003\r\n
s> user-agent: test\r\n
s> content-length: 22\r\n
s> host: $LOCALIP:$HGPORT\r\n (glob)
s> \r\n
s> \x0e\x00\x00\x01\x00\x01\x01\x11\xa1DnameGpushkey
s> makefile('rb', None)
s> HTTP/1.1 403 Forbidden\r\n
s> Server: testing stub value\r\n
s> Date: $HTTP_DATE$\r\n
s> Content-Type: text/plain\r\n
s> Content-Length: 52\r\n
s> \r\n
s> insufficient permissions to execute command: pushkey
$ cat error.log