# -*- coding: utf-8 -*-
# Copyright 2017 New Vector Ltd
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
import gc
import logging
import sys
try:
import affinity
except Exception:
affinity = None
from daemonize import Daemonize
from synapse.util import PreserveLoggingContext
from synapse.util.rlimit import change_resource_limit
from twisted.internet import error, reactor
logger = logging.getLogger(__name__)
def start_worker_reactor(appname, config):
""" Run the reactor in the main process
Daemonizes if necessary, and then configures some resources, before starting
the reactor. Pulls configuration from the 'worker' settings in 'config'.
Args:
appname (str): application name which will be sent to syslog
config (synapse.config.Config): config object
"""
logger = logging.getLogger(config.worker_app)
start_reactor(
appname,
config.soft_file_limit,
config.gc_thresholds,
config.worker_pid_file,
config.worker_daemonize,
config.worker_cpu_affinity,
logger,
)
def start_reactor(
appname,
soft_file_limit,
gc_thresholds,
pid_file,
daemonize,
cpu_affinity,
logger,
):
""" Run the reactor in the main process
Daemonizes if necessary, and then configures some resources, before starting
the reactor
Args:
appname (str): application name which will be sent to syslog
soft_file_limit (int):
gc_thresholds:
pid_file (str): name of pid file to write to if daemonize is True
daemonize (bool): true to run the reactor in a background process
cpu_affinity (int|None): cpu affinity mask
logger (logging.Logger): logger instance to pass to Daemonize
"""
def run():
# make sure that we run the reactor with the sentinel log context,
# otherwise other PreserveLoggingContext instances will get confused
# and complain when they see the logcontext arbitrarily swapping
# between the sentinel and `run` logcontexts.
with PreserveLoggingContext():
logger.info("Running")
if cpu_affinity is not None:
if not affinity:
quit_with_error(
"Missing package 'affinity' required for cpu_affinity\n"
"option\n\n"
"Install by running:\n\n"
" pip install affinity\n\n"
)
logger.info("Setting CPU affinity to %s" % cpu_affinity)
affinity.set_process_affinity_mask(0, cpu_affinity)
change_resource_limit(soft_file_limit)
if gc_thresholds:
gc.set_threshold(*gc_thresholds)
reactor.run()
if daemonize:
daemon = Daemonize(
app=appname,
pid=pid_file,
action=run,
auto_close_fds=False,
verbose=True,
logger=logger,
)
daemon.start()
else:
run()
def quit_with_error(error_string):
message_lines = error_string.split("\n")
line_length = max([len(l) for l in message_lines if len(l) < 80]) + 2
sys.stderr.write("*" * line_length + '\n')
for line in message_lines:
sys.stderr.write(" %s\n" % (line.rstrip(),))
sys.stderr.write("*" * line_length + '\n')
sys.exit(1)
def listen_metrics(bind_addresses, port):
"""
Start Prometheus metrics server.
"""
from synapse.metrics import RegistryProxy
from prometheus_client import start_http_server
for host in bind_addresses:
reactor.callInThread(start_http_server, int(port),
addr=host, registry=RegistryProxy)
logger.info("Metrics now reporting on %s:%d", host, port)
def listen_tcp(bind_addresses, port, factory, backlog=50):
"""
Create a TCP socket for a port and several addresses
"""
for address in bind_addresses:
try:
reactor.listenTCP(
port,
factory,
backlog,
address
)
except error.CannotListenError as e:
check_bind_error(e, address, bind_addresses)
def listen_ssl(bind_addresses, port, factory, context_factory, backlog=50):
"""
Create an SSL socket for a port and several addresses
"""
for address in bind_addresses:
try:
reactor.listenSSL(
port,
factory,
context_factory,
backlog,
address
)
except error.CannotListenError as e:
check_bind_error(e, address, bind_addresses)
def check_bind_error(e, address, bind_addresses):
"""
This method checks an exception occurred while binding on 0.0.0.0.
If :: is specified in the bind addresses a warning is shown.
The exception is still raised otherwise.
Binding on both 0.0.0.0 and :: causes an exception on Linux and macOS
because :: binds on both IPv4 and IPv6 (as per RFC 3493).
When binding on 0.0.0.0 after :: this can safely be ignored.
Args:
e (Exception): Exception that was caught.
address (str): Address on which binding was attempted.
bind_addresses (list): Addresses on which the service listens.
"""
if address == '0.0.0.0' and '::' in bind_addresses:
logger.warn('Failed to listen on 0.0.0.0, continuing because listening on [::]')
else:
raise e