tests/wireprotohelpers.sh

wireprotov2: client support for following content redirects

And with the server actually sending content redirects, it is finally
time to implement client support for following them!

When a redirect response is seen, we wait until all data for that
request has been received (it should be nearly immediate since no
data is expected to follow the redirect message). Then we use
a URL opener to make a request. We stuff that response into the
client handler and construct a new response object to track it.

When readdata() is called for servicing requests, we attempt to
read data from the first redirected response. During data reading,
data is processed similarly to as if it came from a frame payload.

The existing test for the functionality demonstrates the client
transparently following the redirect and obtaining the command
response data from an alternate URL!

There is still plenty of work to do here, including shoring up
testing. I'm not convinced things will work in the presence of
multiple redirect responses. And we don't yet implement support
for integrity verification or configuring server certificates
to validate the connection. But it's a start. And it should enable
us to start experimenting with "real" caches.

Differential Revision: https://phab.mercurial-scm.org/D4778

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
}