view tests/notcapable @ 50443:3b199593fedd

hidden: add support to explicitly access hidden changesets via HTTP

We now detect hidden access request and validate them while handling HTTP
wireprotocol command. This changeset only introduces server support. Client
support is added in a subsequent changeset.

The mechanism we use for the HTTP wireprotocol is the same as the one used to
lift filtering for hgweb. The use of the global `access-hidden` parameter in
the http url is a simple and effective approach that

* works around the lack of global parameters in wire protocol v1,
* reuses the mechanism used for hgweb (that does not use the wireproto), and
* can be safely ignored by older client (fitting the best effort contract).

The feature is still experimental, so we can easily update the implementation
details in the future. However, landing a first implementation now will help
test the feature in the wild and iterate on alternative implementations if
deemed necessary.

# Disable the $CAP wire protocol capability.

if test -z "$CAP"
then
    echo "CAP environment variable not set."
fi

cat > notcapable-$CAP.py << EOF
from mercurial import extensions, localrepo
from mercurial.interfaces import repository
def extsetup(ui):
    extensions.wrapfunction(repository.peer, 'capable', wrapcapable)
    extensions.wrapfunction(localrepo.localrepository, 'peer', wrappeer)
def wrapcapable(orig, self, name, *args, **kwargs):
    if name in b'$CAP'.split(b' '):
        return False
    return orig(self, name, *args, **kwargs)
def wrappeer(orig, self, *args, **kwargs):
    # Since we're disabling some newer features, we need to make sure local
    # repos add in the legacy features again.
    return localrepo.locallegacypeer(self, *args, **kwargs)
EOF

echo '[extensions]' >> $HGRCPATH
echo "notcapable-$CAP = `pwd`/notcapable-$CAP.py" >> $HGRCPATH