wireprotov2: change how revisions are specified to changesetdata
Right now, we have a handful of arguments for specifying the revisions
whose data should be returned. Defining how all these arguments
interact when various combinations are present is difficult.
This commit establishes a new, generic mechanism for specifying
revisions. Instead of a hodgepodge of arguments defining things, we
have a list of dicts that specify revision selectors. The final set
of revisions is a union of all these selectors.
We implement support for specifying revisions based on:
* An explicit list of changeset revisions
* An explicit list of changeset revisions plus ancestry depth
* A DAG range between changeset roots and heads
If you squint hard enough, this problem has already been solved by
revsets. But I'm reluctant to expose revsets to the wire protocol
because that would require servers to implement a revset parser.
Plus there are security and performance implications: the set
of revision selectors needs to be narrowly and specifically tailored
for what is appropriate to be executing on a server. Perhaps there
would be a way for us to express the "parse tree" of a revset
query, for example. I'm not sure. We can explore this space another
time. For now, the new mechanism should bring sufficient flexibility
while remaining relatively simple.
The selector "types" are prefixed with "changeset" because I plan
to add manifest and file-flavored selectors as well. This will enable
us to e.g. select file revisions based on a range of changeset
revisions.
Differential Revision: https://phab.mercurial-scm.org/D4979
HTTPV2=exp-http-v2-0003
MEDIATYPE=application/mercurial-exp-framing-0006
sendhttpraw() {
hg --verbose debugwireproto --peer raw http://$LOCALIP:$HGPORT/
}
sendhttpv2peer() {
hg --config experimental.httppeer.v2-encoder-order=identity debugwireproto --nologhandshake --peer http2 http://$LOCALIP:$HGPORT/
}
sendhttpv2peerverbose() {
hg --config experimental.httppeer.v2-encoder-order=identity --verbose debugwireproto --nologhandshake --peer http2 http://$LOCALIP:$HGPORT/
}
sendhttpv2peerhandshake() {
hg --config experimental.httppeer.v2-encoder-order=identity --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
# So tests are in plain text. Also, zstd isn't available in all installs,
# which would make tests non-deterministic.
httppeer.v2-encoder-order = identity
EOF
}