tests/test-wireproto-command-filedata.t

wireprotov2: allow multiple fields to follow revision maps

The *data wire protocol commands emit a series of CBOR values.
Because revision/delta data may be large, their data is emitted
outside the map as a top-level bytestring value.

Before this commit, we'd emit a single optional bytestring
value after the revision descriptor map. This got the job done.
But it was limiting in that we could only send a single field.
And, it required the consumer to know that the presence of a
key in the map implied the existence of a following bytestring
value.

This commit changes the encoding strategy so top-level bytestring
values in the stream are explicitly denoted in a "fieldsfollowing"
key. This key contains an array defining what fields that follow
and the expected size of each field.

By defining things this way, we can easily send N bytestring
values without any ambiguity about their order. In addition,
clients only need to know how to parse ``fieldsfollowing`` to
know if extra values are present.

Because this breaks backwards compatibility, we've bumped the version
number of the wire protocol version 2 API endpoint.

Differential Revision: https://phab.mercurial-scm.org/D4620

  $ . $TESTDIR/wireprotohelpers.sh

  $ hg init server
  $ enablehttpv2 server
  $ cd server
  $ echo a0 > a
  $ echo b0 > b
  $ mkdir -p dir0/child0 dir0/child1 dir1
  $ echo c0 > dir0/c
  $ echo d0 > dir0/d
  $ echo e0 > dir0/child0/e
  $ echo f0 > dir0/child1/f
  $ hg -q commit -A -m 'commit 0'

  $ echo a1 > a
  $ echo d1 > dir0/d
  $ hg commit -m 'commit 1'
  $ echo f0 > dir0/child1/f
  $ hg commit -m 'commit 2'
  nothing changed
  [1]

  $ hg -q up -r 0
  $ echo a2 > a
  $ hg commit -m 'commit 3'
  created new head

  $ hg log -G -T '{rev}:{node} {desc}\n'
  @  2:c8757a2ffe552850d1e0dfe60d295ebf64c196d9 commit 3
  |
  | o  1:650165e803375748a94df471e5b58d85763e0b29 commit 1
  |/
  o  0:6d85ca1270b377d320098556ba5bfad34a9ee12d commit 0
  

  $ hg --debug debugindex a
     rev linkrev nodeid                                   p1                                       p2
       0       0 2b4eb07319bfa077a40a2f04913659aef0da42da 0000000000000000000000000000000000000000 0000000000000000000000000000000000000000
       1       1 9a38122997b3ac97be2a9aa2e556838341fdf2cc 2b4eb07319bfa077a40a2f04913659aef0da42da 0000000000000000000000000000000000000000
       2       2 0879345e39377229634b420c639454156726c6b6 2b4eb07319bfa077a40a2f04913659aef0da42da 0000000000000000000000000000000000000000

  $ hg --debug debugindex dir0/child0/e
     rev linkrev nodeid                                   p1                                       p2
       0       0 bbba6c06b30f443d34ff841bc985c4d0827c6be4 0000000000000000000000000000000000000000 0000000000000000000000000000000000000000

  $ hg serve -p $HGPORT -d --pid-file hg.pid -E error.log
  $ cat hg.pid > $DAEMON_PIDS

Missing arguments is an error

  $ sendhttpv2peer << EOF
  > command filedata
  > EOF
  creating http peer for wire protocol version 2
  sending filedata command
  s>     POST /api/exp-http-v2-0001/ro/filedata HTTP/1.1\r\n
  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: 23\r\n
  s>     host: $LOCALIP:$HGPORT\r\n (glob)
  s>     user-agent: Mercurial debugwireproto\r\n
  s>     \r\n
  s>     \x0f\x00\x00\x01\x00\x01\x01\x11\xa1DnameHfiledata
  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>     4e\r\n
  s>     F\x00\x00\x01\x00\x02\x012
  s>     \xa2Eerror\xa1GmessageX\'missing required arguments: nodes, pathFstatusEerror
  s>     \r\n
  received frame(size=70; request=1; stream=2; streamflags=stream-begin; type=command-response; flags=eos)
  s>     0\r\n
  s>     \r\n
  abort: missing required arguments: nodes, path!
  [255]

  $ sendhttpv2peer << EOF
  > command filedata
  >     nodes eval:[]
  > EOF
  creating http peer for wire protocol version 2
  sending filedata command
  s>     POST /api/exp-http-v2-0001/ro/filedata HTTP/1.1\r\n
  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: 36\r\n
  s>     host: $LOCALIP:$HGPORT\r\n (glob)
  s>     user-agent: Mercurial debugwireproto\r\n
  s>     \r\n
  s>     \x1c\x00\x00\x01\x00\x01\x01\x11\xa2Dargs\xa1Enodes\x80DnameHfiledata
  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>     47\r\n
  s>     ?\x00\x00\x01\x00\x02\x012
  s>     \xa2Eerror\xa1GmessageX missing required arguments: pathFstatusEerror
  s>     \r\n
  received frame(size=63; request=1; stream=2; streamflags=stream-begin; type=command-response; flags=eos)
  s>     0\r\n
  s>     \r\n
  abort: missing required arguments: path!
  [255]

Unknown node is an error

  $ sendhttpv2peer << EOF
  > command filedata
  >     nodes eval:[b'\xaa\xaa\xaa\xaa\xaa\xaa\xaa\xaa\xaa\xaa\xaa\xaa\xaa\xaa\xaa\xaa\xaa\xaa\xaa\xaa']
  >     path eval:b'a'
  > EOF
  creating http peer for wire protocol version 2
  sending filedata command
  s>     POST /api/exp-http-v2-0001/ro/filedata HTTP/1.1\r\n
  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: 64\r\n
  s>     host: $LOCALIP:$HGPORT\r\n (glob)
  s>     user-agent: Mercurial debugwireproto\r\n
  s>     \r\n
  s>     8\x00\x00\x01\x00\x01\x01\x11\xa2Dargs\xa2Enodes\x81T\xaa\xaa\xaa\xaa\xaa\xaa\xaa\xaa\xaa\xaa\xaa\xaa\xaa\xaa\xaa\xaa\xaa\xaa\xaa\xaaDpathAaDnameHfiledata
  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>     6b\r\n
  s>     c\x00\x00\x01\x00\x02\x012
  s>     \xa2Eerror\xa2Dargs\x81X(aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaGmessageUunknown file node: %sFstatusEerror
  s>     \r\n
  received frame(size=99; request=1; stream=2; streamflags=stream-begin; type=command-response; flags=eos)
  s>     0\r\n
  s>     \r\n
  abort: unknown file node: aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa!
  [255]

Fetching a single revision returns just metadata by default

  $ sendhttpv2peer << EOF
  > command filedata
  >     nodes eval:[b'\x9a\x38\x12\x29\x97\xb3\xac\x97\xbe\x2a\x9a\xa2\xe5\x56\x83\x83\x41\xfd\xf2\xcc']
  >     path eval:b'a'
  > EOF
  creating http peer for wire protocol version 2
  sending filedata command
  s>     POST /api/exp-http-v2-0001/ro/filedata HTTP/1.1\r\n
  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: 64\r\n
  s>     host: $LOCALIP:$HGPORT\r\n (glob)
  s>     user-agent: Mercurial debugwireproto\r\n
  s>     \r\n
  s>     8\x00\x00\x01\x00\x01\x01\x11\xa2Dargs\xa2Enodes\x81T\x9a8\x12)\x97\xb3\xac\x97\xbe*\x9a\xa2\xe5V\x83\x83A\xfd\xf2\xccDpathAaDnameHfiledata
  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>     13\r\n
  s>     \x0b\x00\x00\x01\x00\x02\x011
  s>     \xa1FstatusBok
  s>     \r\n
  received frame(size=11; request=1; stream=2; streamflags=stream-begin; type=command-response; flags=continuation)
  s>     30\r\n
  s>     (\x00\x00\x01\x00\x02\x001
  s>     \xa1Jtotalitems\x01\xa1DnodeT\x9a8\x12)\x97\xb3\xac\x97\xbe*\x9a\xa2\xe5V\x83\x83A\xfd\xf2\xcc
  s>     \r\n
  received frame(size=40; request=1; stream=2; streamflags=; type=command-response; flags=continuation)
  s>     8\r\n
  s>     \x00\x00\x00\x01\x00\x02\x002
  s>     \r\n
  s>     0\r\n
  s>     \r\n
  received frame(size=0; request=1; stream=2; streamflags=; type=command-response; flags=eos)
  response: gen[
    {
      b'totalitems': 1
    },
    {
      b'node': b'\x9a8\x12)\x97\xb3\xac\x97\xbe*\x9a\xa2\xe5V\x83\x83A\xfd\xf2\xcc'
    }
  ]

Requesting parents works

  $ sendhttpv2peer << EOF
  > command filedata
  >     nodes eval:[b'\x9a\x38\x12\x29\x97\xb3\xac\x97\xbe\x2a\x9a\xa2\xe5\x56\x83\x83\x41\xfd\xf2\xcc']
  >     path eval:b'a'
  >     fields eval:[b'parents']
  > EOF
  creating http peer for wire protocol version 2
  sending filedata command
  s>     POST /api/exp-http-v2-0001/ro/filedata HTTP/1.1\r\n
  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: 80\r\n
  s>     host: $LOCALIP:$HGPORT\r\n (glob)
  s>     user-agent: Mercurial debugwireproto\r\n
  s>     \r\n
  s>     H\x00\x00\x01\x00\x01\x01\x11\xa2Dargs\xa3Ffields\x81GparentsEnodes\x81T\x9a8\x12)\x97\xb3\xac\x97\xbe*\x9a\xa2\xe5V\x83\x83A\xfd\xf2\xccDpathAaDnameHfiledata
  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>     13\r\n
  s>     \x0b\x00\x00\x01\x00\x02\x011
  s>     \xa1FstatusBok
  s>     \r\n
  received frame(size=11; request=1; stream=2; streamflags=stream-begin; type=command-response; flags=continuation)
  s>     63\r\n
  s>     [\x00\x00\x01\x00\x02\x001
  s>     \xa1Jtotalitems\x01\xa2DnodeT\x9a8\x12)\x97\xb3\xac\x97\xbe*\x9a\xa2\xe5V\x83\x83A\xfd\xf2\xccGparents\x82T+N\xb0s\x19\xbf\xa0w\xa4\n
  s>     /\x04\x916Y\xae\xf0\xdaB\xdaT\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00
  s>     \r\n
  received frame(size=91; request=1; stream=2; streamflags=; type=command-response; flags=continuation)
  s>     8\r\n
  s>     \x00\x00\x00\x01\x00\x02\x002
  s>     \r\n
  s>     0\r\n
  s>     \r\n
  received frame(size=0; request=1; stream=2; streamflags=; type=command-response; flags=eos)
  response: gen[
    {
      b'totalitems': 1
    },
    {
      b'node': b'\x9a8\x12)\x97\xb3\xac\x97\xbe*\x9a\xa2\xe5V\x83\x83A\xfd\xf2\xcc',
      b'parents': [
        b'+N\xb0s\x19\xbf\xa0w\xa4\n/\x04\x916Y\xae\xf0\xdaB\xda',
        b'\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00'
      ]
    }
  ]

Requesting revision data works
(haveparents defaults to False, so fulltext is emitted)

  $ sendhttpv2peer << EOF
  > command filedata
  >     nodes eval:[b'\x9a\x38\x12\x29\x97\xb3\xac\x97\xbe\x2a\x9a\xa2\xe5\x56\x83\x83\x41\xfd\xf2\xcc']
  >     path eval:b'a'
  >     fields eval:[b'revision']
  > EOF
  creating http peer for wire protocol version 2
  sending filedata command
  s>     POST /api/exp-http-v2-0001/ro/filedata HTTP/1.1\r\n
  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: 81\r\n
  s>     host: $LOCALIP:$HGPORT\r\n (glob)
  s>     user-agent: Mercurial debugwireproto\r\n
  s>     \r\n
  s>     I\x00\x00\x01\x00\x01\x01\x11\xa2Dargs\xa3Ffields\x81HrevisionEnodes\x81T\x9a8\x12)\x97\xb3\xac\x97\xbe*\x9a\xa2\xe5V\x83\x83A\xfd\xf2\xccDpathAaDnameHfiledata
  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>     13\r\n
  s>     \x0b\x00\x00\x01\x00\x02\x011
  s>     \xa1FstatusBok
  s>     \r\n
  received frame(size=11; request=1; stream=2; streamflags=stream-begin; type=command-response; flags=continuation)
  s>     50\r\n
  s>     H\x00\x00\x01\x00\x02\x001
  s>     \xa1Jtotalitems\x01\xa2Ofieldsfollowing\x81\x82Hrevision\x03DnodeT\x9a8\x12)\x97\xb3\xac\x97\xbe*\x9a\xa2\xe5V\x83\x83A\xfd\xf2\xccCa1\n
  s>     \r\n
  received frame(size=72; request=1; stream=2; streamflags=; type=command-response; flags=continuation)
  s>     8\r\n
  s>     \x00\x00\x00\x01\x00\x02\x002
  s>     \r\n
  s>     0\r\n
  s>     \r\n
  received frame(size=0; request=1; stream=2; streamflags=; type=command-response; flags=eos)
  response: gen[
    {
      b'totalitems': 1
    },
    {
      b'fieldsfollowing': [
        [
          b'revision',
          3
        ]
      ],
      b'node': b'\x9a8\x12)\x97\xb3\xac\x97\xbe*\x9a\xa2\xe5V\x83\x83A\xfd\xf2\xcc'
    },
    b'a1\n'
  ]

haveparents=False should be same as above

  $ sendhttpv2peer << EOF
  > command filedata
  >     nodes eval:[b'\x9a\x38\x12\x29\x97\xb3\xac\x97\xbe\x2a\x9a\xa2\xe5\x56\x83\x83\x41\xfd\xf2\xcc']
  >     path eval:b'a'
  >     fields eval:[b'revision']
  >     haveparents eval:False
  > EOF
  creating http peer for wire protocol version 2
  sending filedata command
  s>     POST /api/exp-http-v2-0001/ro/filedata HTTP/1.1\r\n
  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: 94\r\n
  s>     host: $LOCALIP:$HGPORT\r\n (glob)
  s>     user-agent: Mercurial debugwireproto\r\n
  s>     \r\n
  s>     V\x00\x00\x01\x00\x01\x01\x11\xa2Dargs\xa4Ffields\x81HrevisionKhaveparents\xf4Enodes\x81T\x9a8\x12)\x97\xb3\xac\x97\xbe*\x9a\xa2\xe5V\x83\x83A\xfd\xf2\xccDpathAaDnameHfiledata
  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>     13\r\n
  s>     \x0b\x00\x00\x01\x00\x02\x011
  s>     \xa1FstatusBok
  s>     \r\n
  received frame(size=11; request=1; stream=2; streamflags=stream-begin; type=command-response; flags=continuation)
  s>     50\r\n
  s>     H\x00\x00\x01\x00\x02\x001
  s>     \xa1Jtotalitems\x01\xa2Ofieldsfollowing\x81\x82Hrevision\x03DnodeT\x9a8\x12)\x97\xb3\xac\x97\xbe*\x9a\xa2\xe5V\x83\x83A\xfd\xf2\xccCa1\n
  s>     \r\n
  received frame(size=72; request=1; stream=2; streamflags=; type=command-response; flags=continuation)
  s>     8\r\n
  s>     \x00\x00\x00\x01\x00\x02\x002
  s>     \r\n
  s>     0\r\n
  s>     \r\n
  received frame(size=0; request=1; stream=2; streamflags=; type=command-response; flags=eos)
  response: gen[
    {
      b'totalitems': 1
    },
    {
      b'fieldsfollowing': [
        [
          b'revision',
          3
        ]
      ],
      b'node': b'\x9a8\x12)\x97\xb3\xac\x97\xbe*\x9a\xa2\xe5V\x83\x83A\xfd\xf2\xcc'
    },
    b'a1\n'
  ]

haveparents=True should emit a delta

  $ sendhttpv2peer << EOF
  > command filedata
  >     nodes eval:[b'\x9a\x38\x12\x29\x97\xb3\xac\x97\xbe\x2a\x9a\xa2\xe5\x56\x83\x83\x41\xfd\xf2\xcc']
  >     path eval:b'a'
  >     fields eval:[b'revision']
  >     haveparents eval:True
  > EOF
  creating http peer for wire protocol version 2
  sending filedata command
  s>     POST /api/exp-http-v2-0001/ro/filedata HTTP/1.1\r\n
  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: 94\r\n
  s>     host: $LOCALIP:$HGPORT\r\n (glob)
  s>     user-agent: Mercurial debugwireproto\r\n
  s>     \r\n
  s>     V\x00\x00\x01\x00\x01\x01\x11\xa2Dargs\xa4Ffields\x81HrevisionKhaveparents\xf5Enodes\x81T\x9a8\x12)\x97\xb3\xac\x97\xbe*\x9a\xa2\xe5V\x83\x83A\xfd\xf2\xccDpathAaDnameHfiledata
  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>     13\r\n
  s>     \x0b\x00\x00\x01\x00\x02\x011
  s>     \xa1FstatusBok
  s>     \r\n
  received frame(size=11; request=1; stream=2; streamflags=stream-begin; type=command-response; flags=continuation)
  s>     7c\r\n
  s>     t\x00\x00\x01\x00\x02\x001
  s>     \xa1Jtotalitems\x01\xa3MdeltabasenodeT+N\xb0s\x19\xbf\xa0w\xa4\n
  s>     /\x04\x916Y\xae\xf0\xdaB\xdaOfieldsfollowing\x81\x82Edelta\x0fDnodeT\x9a8\x12)\x97\xb3\xac\x97\xbe*\x9a\xa2\xe5V\x83\x83A\xfd\xf2\xccO\x00\x00\x00\x00\x00\x00\x00\x03\x00\x00\x00\x03a1\n
  s>     \r\n
  received frame(size=116; request=1; stream=2; streamflags=; type=command-response; flags=continuation)
  s>     8\r\n
  s>     \x00\x00\x00\x01\x00\x02\x002
  s>     \r\n
  s>     0\r\n
  s>     \r\n
  received frame(size=0; request=1; stream=2; streamflags=; type=command-response; flags=eos)
  response: gen[
    {
      b'totalitems': 1
    },
    {
      b'deltabasenode': b'+N\xb0s\x19\xbf\xa0w\xa4\n/\x04\x916Y\xae\xf0\xdaB\xda',
      b'fieldsfollowing': [
        [
          b'delta',
          15
        ]
      ],
      b'node': b'\x9a8\x12)\x97\xb3\xac\x97\xbe*\x9a\xa2\xe5V\x83\x83A\xfd\xf2\xcc'
    },
    b'\x00\x00\x00\x00\x00\x00\x00\x03\x00\x00\x00\x03a1\n'
  ]

Requesting multiple revisions works
(first revision is a fulltext since haveparents=False by default)

  $ sendhttpv2peer << EOF
  > command filedata
  >     nodes eval:['\x2b\x4e\xb0\x73\x19\xbf\xa0\x77\xa4\x0a\x2f\x04\x91\x36\x59\xae\xf0\xda\x42\xda', '\x9a\x38\x12\x29\x97\xb3\xac\x97\xbe\x2a\x9a\xa2\xe5\x56\x83\x83\x41\xfd\xf2\xcc']
  >     path eval:b'a'
  >     fields eval:[b'revision']
  > EOF
  creating http peer for wire protocol version 2
  sending filedata command
  s>     POST /api/exp-http-v2-0001/ro/filedata HTTP/1.1\r\n
  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: 102\r\n
  s>     host: $LOCALIP:$HGPORT\r\n (glob)
  s>     user-agent: Mercurial debugwireproto\r\n
  s>     \r\n
  s>     ^\x00\x00\x01\x00\x01\x01\x11\xa2Dargs\xa3Ffields\x81HrevisionEnodes\x82T+N\xb0s\x19\xbf\xa0w\xa4\n
  s>     /\x04\x916Y\xae\xf0\xdaB\xdaT\x9a8\x12)\x97\xb3\xac\x97\xbe*\x9a\xa2\xe5V\x83\x83A\xfd\xf2\xccDpathAaDnameHfiledata
  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>     13\r\n
  s>     \x0b\x00\x00\x01\x00\x02\x011
  s>     \xa1FstatusBok
  s>     \r\n
  received frame(size=11; request=1; stream=2; streamflags=stream-begin; type=command-response; flags=continuation)
  s>     b7\r\n
  s>     \xaf\x00\x00\x01\x00\x02\x001
  s>     \xa1Jtotalitems\x02\xa2Ofieldsfollowing\x81\x82Hrevision\x03DnodeT+N\xb0s\x19\xbf\xa0w\xa4\n
  s>     /\x04\x916Y\xae\xf0\xdaB\xdaCa0\n
  s>     \xa3MdeltabasenodeT+N\xb0s\x19\xbf\xa0w\xa4\n
  s>     /\x04\x916Y\xae\xf0\xdaB\xdaOfieldsfollowing\x81\x82Edelta\x0fDnodeT\x9a8\x12)\x97\xb3\xac\x97\xbe*\x9a\xa2\xe5V\x83\x83A\xfd\xf2\xccO\x00\x00\x00\x00\x00\x00\x00\x03\x00\x00\x00\x03a1\n
  s>     \r\n
  received frame(size=175; request=1; stream=2; streamflags=; type=command-response; flags=continuation)
  s>     8\r\n
  s>     \x00\x00\x00\x01\x00\x02\x002
  s>     \r\n
  s>     0\r\n
  s>     \r\n
  received frame(size=0; request=1; stream=2; streamflags=; type=command-response; flags=eos)
  response: gen[
    {
      b'totalitems': 2
    },
    {
      b'fieldsfollowing': [
        [
          b'revision',
          3
        ]
      ],
      b'node': b'+N\xb0s\x19\xbf\xa0w\xa4\n/\x04\x916Y\xae\xf0\xdaB\xda'
    },
    b'a0\n',
    {
      b'deltabasenode': b'+N\xb0s\x19\xbf\xa0w\xa4\n/\x04\x916Y\xae\xf0\xdaB\xda',
      b'fieldsfollowing': [
        [
          b'delta',
          15
        ]
      ],
      b'node': b'\x9a8\x12)\x97\xb3\xac\x97\xbe*\x9a\xa2\xe5V\x83\x83A\xfd\xf2\xcc'
    },
    b'\x00\x00\x00\x00\x00\x00\x00\x03\x00\x00\x00\x03a1\n'
  ]

Revisions are sorted by DAG order, parents first

  $ sendhttpv2peer << EOF
  > command filedata
  >     nodes eval:['\x9a\x38\x12\x29\x97\xb3\xac\x97\xbe\x2a\x9a\xa2\xe5\x56\x83\x83\x41\xfd\xf2\xcc', '\x2b\x4e\xb0\x73\x19\xbf\xa0\x77\xa4\x0a\x2f\x04\x91\x36\x59\xae\xf0\xda\x42\xda']
  >     path eval:b'a'
  >     fields eval:[b'revision']
  > EOF
  creating http peer for wire protocol version 2
  sending filedata command
  s>     POST /api/exp-http-v2-0001/ro/filedata HTTP/1.1\r\n
  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: 102\r\n
  s>     host: $LOCALIP:$HGPORT\r\n (glob)
  s>     user-agent: Mercurial debugwireproto\r\n
  s>     \r\n
  s>     ^\x00\x00\x01\x00\x01\x01\x11\xa2Dargs\xa3Ffields\x81HrevisionEnodes\x82T\x9a8\x12)\x97\xb3\xac\x97\xbe*\x9a\xa2\xe5V\x83\x83A\xfd\xf2\xccT+N\xb0s\x19\xbf\xa0w\xa4\n
  s>     /\x04\x916Y\xae\xf0\xdaB\xdaDpathAaDnameHfiledata
  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>     13\r\n
  s>     \x0b\x00\x00\x01\x00\x02\x011
  s>     \xa1FstatusBok
  s>     \r\n
  received frame(size=11; request=1; stream=2; streamflags=stream-begin; type=command-response; flags=continuation)
  s>     b7\r\n
  s>     \xaf\x00\x00\x01\x00\x02\x001
  s>     \xa1Jtotalitems\x02\xa2Ofieldsfollowing\x81\x82Hrevision\x03DnodeT+N\xb0s\x19\xbf\xa0w\xa4\n
  s>     /\x04\x916Y\xae\xf0\xdaB\xdaCa0\n
  s>     \xa3MdeltabasenodeT+N\xb0s\x19\xbf\xa0w\xa4\n
  s>     /\x04\x916Y\xae\xf0\xdaB\xdaOfieldsfollowing\x81\x82Edelta\x0fDnodeT\x9a8\x12)\x97\xb3\xac\x97\xbe*\x9a\xa2\xe5V\x83\x83A\xfd\xf2\xccO\x00\x00\x00\x00\x00\x00\x00\x03\x00\x00\x00\x03a1\n
  s>     \r\n
  received frame(size=175; request=1; stream=2; streamflags=; type=command-response; flags=continuation)
  s>     8\r\n
  s>     \x00\x00\x00\x01\x00\x02\x002
  s>     \r\n
  s>     0\r\n
  s>     \r\n
  received frame(size=0; request=1; stream=2; streamflags=; type=command-response; flags=eos)
  response: gen[
    {
      b'totalitems': 2
    },
    {
      b'fieldsfollowing': [
        [
          b'revision',
          3
        ]
      ],
      b'node': b'+N\xb0s\x19\xbf\xa0w\xa4\n/\x04\x916Y\xae\xf0\xdaB\xda'
    },
    b'a0\n',
    {
      b'deltabasenode': b'+N\xb0s\x19\xbf\xa0w\xa4\n/\x04\x916Y\xae\xf0\xdaB\xda',
      b'fieldsfollowing': [
        [
          b'delta',
          15
        ]
      ],
      b'node': b'\x9a8\x12)\x97\xb3\xac\x97\xbe*\x9a\xa2\xe5V\x83\x83A\xfd\xf2\xcc'
    },
    b'\x00\x00\x00\x00\x00\x00\x00\x03\x00\x00\x00\x03a1\n'
  ]

Requesting parents and revision data works

  $ sendhttpv2peer << EOF
  > command filedata
  >     nodes eval:['\x08\x79\x34\x5e\x39\x37\x72\x29\x63\x4b\x42\x0c\x63\x94\x54\x15\x67\x26\xc6\xb6']
  >     path eval:b'a'
  >     fields eval:[b'parents', b'revision']
  > EOF
  creating http peer for wire protocol version 2
  sending filedata command
  s>     POST /api/exp-http-v2-0001/ro/filedata HTTP/1.1\r\n
  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: 89\r\n
  s>     host: $LOCALIP:$HGPORT\r\n (glob)
  s>     user-agent: Mercurial debugwireproto\r\n
  s>     \r\n
  s>     Q\x00\x00\x01\x00\x01\x01\x11\xa2Dargs\xa3Ffields\x82GparentsHrevisionEnodes\x81T\x08y4^97r)cKB\x0cc\x94T\x15g&\xc6\xb6DpathAaDnameHfiledata
  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>     13\r\n
  s>     \x0b\x00\x00\x01\x00\x02\x011
  s>     \xa1FstatusBok
  s>     \r\n
  received frame(size=11; request=1; stream=2; streamflags=stream-begin; type=command-response; flags=continuation)
  s>     83\r\n
  s>     {\x00\x00\x01\x00\x02\x001
  s>     \xa1Jtotalitems\x01\xa3Ofieldsfollowing\x81\x82Hrevision\x03DnodeT\x08y4^97r)cKB\x0cc\x94T\x15g&\xc6\xb6Gparents\x82T+N\xb0s\x19\xbf\xa0w\xa4\n
  s>     /\x04\x916Y\xae\xf0\xdaB\xdaT\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00Ca2\n
  s>     \r\n
  received frame(size=123; request=1; stream=2; streamflags=; type=command-response; flags=continuation)
  s>     8\r\n
  s>     \x00\x00\x00\x01\x00\x02\x002
  s>     \r\n
  s>     0\r\n
  s>     \r\n
  received frame(size=0; request=1; stream=2; streamflags=; type=command-response; flags=eos)
  response: gen[
    {
      b'totalitems': 1
    },
    {
      b'fieldsfollowing': [
        [
          b'revision',
          3
        ]
      ],
      b'node': b'\x08y4^97r)cKB\x0cc\x94T\x15g&\xc6\xb6',
      b'parents': [
        b'+N\xb0s\x19\xbf\xa0w\xa4\n/\x04\x916Y\xae\xf0\xdaB\xda',
        b'\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00'
      ]
    },
    b'a2\n'
  ]

  $ cat error.log