##// END OF EJS Templates
wireprotov2peer: stream decoded responses...
wireprotov2peer: stream decoded responses Previously, wire protocol version 2 would buffer all response data. Only once all data was received did we CBOR decode it and resolve the future associated with the command. This was obviously not desirable. In future commits that introduce large response payloads, this caused significant memory bloat and slowed down client operations due to waiting on the server. This commit refactors the response handling code so that response data can be streamed. Command response objects now contain a buffered CBOR decoder. As new data arrives, it is fed into the decoder. Decoded objects are made available to the generator as they are decoded. Because there is a separate thread processing incoming frames and feeding data into the response object, there is the potential for race conditions when mutating response objects. So a lock has been added to guard access to critical state variables. Because the generator emitting decoded objects needs to wait on those objects to become available, we've added an Event for the generator to wait on so it doesn't busy loop. This does mean there is the potential for deadlocks. And I'm pretty sure they can occur in some scenarios. We already have a handful of TODOs around this. But I've added some more. Fixing this will likely require moving the background thread receiving frames into clienthandler. We likely would have done this anyway when implementing the client bits for the SSH transport. Test output changes because the initial CBOR map holding the overall response state is now always handled internally by the response object. Differential Revision: https://phab.mercurial-scm.org/D4474

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hg-docker
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#!/usr/bin/env python3
#
# Copyright 2018 Gregory Szorc <gregory.szorc@gmail.com>
#
# This software may be used and distributed according to the terms of the
# GNU General Public License version 2 or any later version.
import argparse
import pathlib
import shutil
import subprocess
import sys
def get_docker() -> str:
docker = shutil.which('docker.io') or shutil.which('docker')
if not docker:
print('could not find docker executable')
return 1
try:
out = subprocess.check_output([docker, '-h'], stderr=subprocess.STDOUT)
if b'Jansens' in out:
print('%s is the Docking System Tray; try installing docker.io' %
docker)
sys.exit(1)
except subprocess.CalledProcessError as e:
print('error calling `%s -h`: %s' % (docker, e.output))
sys.exit(1)
out = subprocess.check_output([docker, 'version'],
stderr=subprocess.STDOUT)
lines = out.splitlines()
if not any(l.startswith((b'Client:', b'Client version:')) for l in lines):
print('`%s version` does not look like Docker' % docker)
sys.exit(1)
if not any(l.startswith((b'Server:', b'Server version:')) for l in lines):
print('`%s version` does not look like Docker' % docker)
sys.exit(1)
return docker
def get_dockerfile(path: pathlib.Path, args: list) -> bytes:
with path.open('rb') as fh:
df = fh.read()
for k, v in args:
df = df.replace(b'%%%s%%' % k, v)
return df
def build_docker_image(dockerfile: pathlib.Path, params: list, tag: str):
"""Build a Docker image from a templatized Dockerfile."""
docker = get_docker()
dockerfile_path = pathlib.Path(dockerfile)
dockerfile = get_dockerfile(dockerfile_path, params)
print('building Dockerfile:')
print(dockerfile.decode('utf-8', 'replace'))
args = [
docker,
'build',
'--build-arg', 'http_proxy',
'--build-arg', 'https_proxy',
'--tag', tag,
'-',
]
print('executing: %r' % args)
subprocess.run(args, input=dockerfile, check=True)
def command_build(args):
build_args = []
for arg in args.build_arg:
k, v = arg.split('=', 1)
build_args.append((k.encode('utf-8'), v.encode('utf-8')))
build_docker_image(pathlib.Path(args.dockerfile),
build_args,
args.tag)
def command_docker(args):
print(get_docker())
def main() -> int:
parser = argparse.ArgumentParser()
subparsers = parser.add_subparsers(title='subcommands')
build = subparsers.add_parser('build', help='Build a Docker image')
build.set_defaults(func=command_build)
build.add_argument('--build-arg', action='append', default=[],
help='Substitution to perform in Dockerfile; '
'format: key=value')
build.add_argument('dockerfile', help='path to Dockerfile to use')
build.add_argument('tag', help='Tag to apply to created image')
docker = subparsers.add_parser('docker-path', help='Resolve path to Docker')
docker.set_defaults(func=command_docker)
args = parser.parse_args()
return args.func(args)
if __name__ == '__main__':
sys.exit(main())