commandserver: add experimental option to use separate message channel
This is loosely based on the idea of the TortoiseHg's pipeui extension,
which attaches ui.label to message text so the command-server client can
capture prompt text, for example.
https://bitbucket.org/tortoisehg/thg/src/4.7.2/tortoisehg/util/pipeui.py
I was thinking that this functionality could be generalized to templating,
but changed mind as doing template stuff would be unnecessarily complex.
It's merely a status message, a simple serialization option should suffice.
Since this slightly changes the command-server protocol, it's gated by a
config knob. If the config is enabled, and if it's supported by the server,
"message-encoding: <name>" is advertised so the client can stop parsing
'o'/'e' channel data and read encoded messages from the 'm' channel. As we
might add new message encodings in future releases, client can specify a list
of encoding names in preferred order.
This patch includes 'cbor' encoding as example. Perhaps, 'json' should be
supported as well.
#!/usr/bin/env python
# Undump a dump from dumprevlog
# $ hg init
# $ undumprevlog < repo.dump
from __future__ import absolute_import, print_function
import sys
from mercurial import (
encoding,
node,
pycompat,
revlog,
transaction,
vfs as vfsmod,
)
from mercurial.utils import (
procutil,
)
for fp in (sys.stdin, sys.stdout, sys.stderr):
procutil.setbinary(fp)
opener = vfsmod.vfs(b'.', False)
tr = transaction.transaction(sys.stderr.write, opener, {b'store': opener},
b"undump.journal")
while True:
l = sys.stdin.readline()
if not l:
break
if l.startswith("file:"):
f = encoding.strtolocal(l[6:-1])
r = revlog.revlog(opener, f)
pycompat.stdout.write(b'%s\n' % f)
elif l.startswith("node:"):
n = node.bin(l[6:-1])
elif l.startswith("linkrev:"):
lr = int(l[9:-1])
elif l.startswith("parents:"):
p = l[9:-1].split()
p1 = node.bin(p[0])
p2 = node.bin(p[1])
elif l.startswith("length:"):
length = int(l[8:-1])
sys.stdin.readline() # start marker
d = encoding.strtolocal(sys.stdin.read(length))
sys.stdin.readline() # end marker
r.addrevision(d, tr, lr, p1, p2)
tr.close()