wireprotov2: advertise set of valid values for requestable fields
changesetdata, manifestdata, and filedata all allow the caller to
specify what data fields to request.
Data fields are extensible and may evolve over time. In order to
prevent clients from making requests for fields that are not
available, the client needs to know what fields are available.
This commit teaches the server to declare a set of "valid values"
for wire protocol command arguments. That set of values is exposed
in the command's capabilities descriptor. The changesetdata,
manifestdata, and filedata commands all declare their set of
available "fields."
Differential Revision: https://phab.mercurial-scm.org/D4619
# A minimal client for Mercurial's command server
from __future__ import absolute_import, print_function
import os
import signal
import socket
import struct
import subprocess
import sys
import time
try:
import cStringIO as io
stringio = io.StringIO
except ImportError:
import io
stringio = io.StringIO
def connectpipe(path=None):
cmdline = ['hg', 'serve', '--cmdserver', 'pipe']
if path:
cmdline += ['-R', path]
server = subprocess.Popen(cmdline, stdin=subprocess.PIPE,
stdout=subprocess.PIPE)
return server
class unixconnection(object):
def __init__(self, sockpath):
self.sock = sock = socket.socket(socket.AF_UNIX)
sock.connect(sockpath)
self.stdin = sock.makefile('wb')
self.stdout = sock.makefile('rb')
def wait(self):
self.stdin.close()
self.stdout.close()
self.sock.close()
class unixserver(object):
def __init__(self, sockpath, logpath=None, repopath=None):
self.sockpath = sockpath
cmdline = ['hg', 'serve', '--cmdserver', 'unix', '-a', sockpath]
if repopath:
cmdline += ['-R', repopath]
if logpath:
stdout = open(logpath, 'a')
stderr = subprocess.STDOUT
else:
stdout = stderr = None
self.server = subprocess.Popen(cmdline, stdout=stdout, stderr=stderr)
# wait for listen()
while self.server.poll() is None:
if os.path.exists(sockpath):
break
time.sleep(0.1)
def connect(self):
return unixconnection(self.sockpath)
def shutdown(self):
os.kill(self.server.pid, signal.SIGTERM)
self.server.wait()
def writeblock(server, data):
server.stdin.write(struct.pack('>I', len(data)))
server.stdin.write(data)
server.stdin.flush()
def readchannel(server):
data = server.stdout.read(5)
if not data:
raise EOFError
channel, length = struct.unpack('>cI', data)
if channel in 'IL':
return channel, length
else:
return channel, server.stdout.read(length)
def sep(text):
return text.replace('\\', '/')
def runcommand(server, args, output=sys.stdout, error=sys.stderr, input=None,
outfilter=lambda x: x):
print('*** runcommand', ' '.join(args))
sys.stdout.flush()
server.stdin.write('runcommand\n')
writeblock(server, '\0'.join(args))
if not input:
input = stringio()
while True:
ch, data = readchannel(server)
if ch == 'o':
output.write(outfilter(data))
output.flush()
elif ch == 'e':
error.write(data)
error.flush()
elif ch == 'I':
writeblock(server, input.read(data))
elif ch == 'L':
writeblock(server, input.readline(data))
elif ch == 'r':
ret, = struct.unpack('>i', data)
if ret != 0:
print(' [%d]' % ret)
return ret
else:
print("unexpected channel %c: %r" % (ch, data))
if ch.isupper():
return
def check(func, connect=connectpipe):
sys.stdout.flush()
server = connect()
try:
return func(server)
finally:
server.stdin.close()
server.wait()