tests/wireprotohelpers.sh

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

HTTPV2=exp-http-v2-0002
MEDIATYPE=application/mercurial-exp-framing-0005

sendhttpraw() {
  hg --verbose debugwireproto --peer raw http://$LOCALIP:$HGPORT/
}

sendhttpv2peer() {
  hg --verbose debugwireproto --nologhandshake --peer http2 http://$LOCALIP:$HGPORT/
}

sendhttpv2peerhandshake() {
  hg --verbose debugwireproto --peer http2 http://$LOCALIP:$HGPORT/
}

cat > dummycommands.py << EOF
from mercurial import (
    wireprototypes,
    wireprotov1server,
    wireprotov2server,
)

@wireprotov1server.wireprotocommand(b'customreadonly', permission=b'pull')
def customreadonlyv1(repo, proto):
    return wireprototypes.bytesresponse(b'customreadonly bytes response')

@wireprotov2server.wireprotocommand(b'customreadonly', permission=b'pull')
def customreadonlyv2(repo, proto):
    yield b'customreadonly bytes response'

@wireprotov1server.wireprotocommand(b'customreadwrite', permission=b'push')
def customreadwrite(repo, proto):
    return wireprototypes.bytesresponse(b'customreadwrite bytes response')

@wireprotov2server.wireprotocommand(b'customreadwrite', permission=b'push')
def customreadwritev2(repo, proto):
    yield b'customreadwrite bytes response'
EOF

cat >> $HGRCPATH << EOF
[extensions]
drawdag = $TESTDIR/drawdag.py
EOF

enabledummycommands() {
  cat >> $HGRCPATH << EOF
[extensions]
dummycommands = $TESTTMP/dummycommands.py
EOF
}

enablehttpv2() {
  cat >> $1/.hg/hgrc << EOF
[experimental]
web.apiserver = true
web.api.http-v2 = true
EOF
}

enablehttpv2client() {
  cat >> $HGRCPATH << EOF
[experimental]
httppeer.advertise-v2 = true
EOF
}