forked-synapse/synapse/config/logger.py
Richard van der Hoff 8d156ec0ba
Remove special-case for twisted logger (#12589)
This was originally added when we first added a `MemoryHandler` to the default
log config back in https://github.com/matrix-org/synapse/pull/8040, to ensure
that we didn't explode with an infinite loop if there was an error formatting
the logs.

Since then, we made additional improvements to logging which make this
workaround redundant. In particular:

 * we no longer attempt to log un-UTF8-decodable byte sequences, which were the
   most likely cause of an error in the first place.

 * https://github.com/matrix-org/synapse/pull/8268 ensures that in the unlikely
   case that there *is* an error, it won't cause an infinite loop.
2022-04-29 22:05:18 +01:00

356 lines
12 KiB
Python

# Copyright 2014-2016 OpenMarket Ltd
# Copyright 2021 The Matrix.org Foundation C.I.C.
#
# 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 argparse
import logging
import logging.config
import os
import sys
import threading
from string import Template
from typing import TYPE_CHECKING, Any, Dict, Optional
import yaml
from matrix_common.versionstring import get_distribution_version_string
from zope.interface import implementer
from twisted.logger import (
ILogObserver,
LogBeginner,
STDLibLogObserver,
eventAsText,
globalLogBeginner,
)
from synapse.logging.context import LoggingContextFilter
from synapse.logging.filter import MetadataFilter
from synapse.types import JsonDict
from ._base import Config, ConfigError
if TYPE_CHECKING:
from synapse.config.homeserver import HomeServerConfig
from synapse.server import HomeServer
DEFAULT_LOG_CONFIG = Template(
"""\
# Log configuration for Synapse.
#
# This is a YAML file containing a standard Python logging configuration
# dictionary. See [1] for details on the valid settings.
#
# Synapse also supports structured logging for machine readable logs which can
# be ingested by ELK stacks. See [2] for details.
#
# [1]: https://docs.python.org/3.7/library/logging.config.html#configuration-dictionary-schema
# [2]: https://matrix-org.github.io/synapse/latest/structured_logging.html
version: 1
formatters:
precise:
format: '%(asctime)s - %(name)s - %(lineno)d - %(levelname)s - \
%(request)s - %(message)s'
handlers:
file:
class: logging.handlers.TimedRotatingFileHandler
formatter: precise
filename: ${log_file}
when: midnight
backupCount: 3 # Does not include the current log file.
encoding: utf8
# Default to buffering writes to log file for efficiency.
# WARNING/ERROR logs will still be flushed immediately, but there will be a
# delay (of up to `period` seconds, or until the buffer is full with
# `capacity` messages) before INFO/DEBUG logs get written.
buffer:
class: synapse.logging.handlers.PeriodicallyFlushingMemoryHandler
target: file
# The capacity is the maximum number of log lines that are buffered
# before being written to disk. Increasing this will lead to better
# performance, at the expensive of it taking longer for log lines to
# be written to disk.
# This parameter is required.
capacity: 10
# Logs with a level at or above the flush level will cause the buffer to
# be flushed immediately.
# Default value: 40 (ERROR)
# Other values: 50 (CRITICAL), 30 (WARNING), 20 (INFO), 10 (DEBUG)
flushLevel: 30 # Flush immediately for WARNING logs and higher
# The period of time, in seconds, between forced flushes.
# Messages will not be delayed for longer than this time.
# Default value: 5 seconds
period: 5
# A handler that writes logs to stderr. Unused by default, but can be used
# instead of "buffer" and "file" in the logger handlers.
console:
class: logging.StreamHandler
formatter: precise
loggers:
synapse.storage.SQL:
# beware: increasing this to DEBUG will make synapse log sensitive
# information such as access tokens.
level: INFO
root:
level: INFO
# Write logs to the `buffer` handler, which will buffer them together in memory,
# then write them to a file.
#
# Replace "buffer" with "console" to log to stderr instead. (Note that you'll
# also need to update the configuration for the `twisted` logger above, in
# this case.)
#
handlers: [buffer]
disable_existing_loggers: false
"""
)
LOG_FILE_ERROR = """\
Support for the log_file configuration option and --log-file command-line option was
removed in Synapse 1.3.0. You should instead set up a separate log configuration file.
"""
STRUCTURED_ERROR = """\
Support for the structured configuration option was removed in Synapse 1.54.0.
You should instead use the standard logging configuration. See
https://matrix-org.github.io/synapse/v1.54/structured_logging.html
"""
class LoggingConfig(Config):
section = "logging"
def read_config(self, config: JsonDict, **kwargs: Any) -> None:
if config.get("log_file"):
raise ConfigError(LOG_FILE_ERROR)
self.log_config = self.abspath(config.get("log_config"))
self.no_redirect_stdio = config.get("no_redirect_stdio", False)
def generate_config_section(
self, config_dir_path: str, server_name: str, **kwargs: Any
) -> str:
log_config = os.path.join(config_dir_path, server_name + ".log.config")
return (
"""\
## Logging ##
# A yaml python logging config file as described by
# https://docs.python.org/3.7/library/logging.config.html#configuration-dictionary-schema
#
log_config: "%(log_config)s"
"""
% locals()
)
def read_arguments(self, args: argparse.Namespace) -> None:
if args.no_redirect_stdio is not None:
self.no_redirect_stdio = args.no_redirect_stdio
if args.log_file is not None:
raise ConfigError(LOG_FILE_ERROR)
@staticmethod
def add_arguments(parser: argparse.ArgumentParser) -> None:
logging_group = parser.add_argument_group("logging")
logging_group.add_argument(
"-n",
"--no-redirect-stdio",
action="store_true",
default=None,
help="Do not redirect stdout/stderr to the log",
)
logging_group.add_argument(
"-f",
"--log-file",
dest="log_file",
help=argparse.SUPPRESS,
)
def generate_files(self, config: Dict[str, Any], config_dir_path: str) -> None:
log_config = config.get("log_config")
if log_config and not os.path.exists(log_config):
log_file = self.abspath("homeserver.log")
print(
"Generating log config file %s which will log to %s"
% (log_config, log_file)
)
with open(log_config, "w") as log_config_file:
log_config_file.write(DEFAULT_LOG_CONFIG.substitute(log_file=log_file))
def _setup_stdlib_logging(
config: "HomeServerConfig", log_config_path: Optional[str], logBeginner: LogBeginner
) -> None:
"""
Set up Python standard library logging.
"""
if log_config_path is None:
log_format = (
"%(asctime)s - %(name)s - %(lineno)d - %(levelname)s - %(request)s"
" - %(message)s"
)
logger = logging.getLogger("")
logger.setLevel(logging.INFO)
logging.getLogger("synapse.storage.SQL").setLevel(logging.INFO)
formatter = logging.Formatter(log_format)
handler = logging.StreamHandler()
handler.setFormatter(formatter)
logger.addHandler(handler)
else:
# Load the logging configuration.
_load_logging_config(log_config_path)
# We add a log record factory that runs all messages through the
# LoggingContextFilter so that we get the context *at the time we log*
# rather than when we write to a handler. This can be done in config using
# filter options, but care must when using e.g. MemoryHandler to buffer
# writes.
log_context_filter = LoggingContextFilter()
log_metadata_filter = MetadataFilter({"server_name": config.server.server_name})
old_factory = logging.getLogRecordFactory()
def factory(*args: Any, **kwargs: Any) -> logging.LogRecord:
record = old_factory(*args, **kwargs)
log_context_filter.filter(record)
log_metadata_filter.filter(record)
return record
logging.setLogRecordFactory(factory)
# Route Twisted's native logging through to the standard library logging
# system.
observer = STDLibLogObserver()
threadlocal = threading.local()
@implementer(ILogObserver)
def _log(event: dict) -> None:
if "log_text" in event:
if event["log_text"].startswith("DNSDatagramProtocol starting on "):
return
if event["log_text"].startswith("(UDP Port "):
return
if event["log_text"].startswith("Timing out client"):
return
# this is a workaround to make sure we don't get stack overflows when the
# logging system raises an error which is written to stderr which is redirected
# to the logging system, etc.
if getattr(threadlocal, "active", False):
# write the text of the event, if any, to the *real* stderr (which may
# be redirected to /dev/null, but there's not much we can do)
try:
event_text = eventAsText(event)
print("logging during logging: %s" % event_text, file=sys.__stderr__)
except Exception:
# gah.
pass
return
try:
threadlocal.active = True
return observer(event)
finally:
threadlocal.active = False
logBeginner.beginLoggingTo([_log], redirectStandardIO=False)
def _load_logging_config(log_config_path: str) -> None:
"""
Configure logging from a log config path.
"""
with open(log_config_path, "rb") as f:
log_config = yaml.safe_load(f.read())
if not log_config:
logging.warning("Loaded a blank logging config?")
# If the old structured logging configuration is being used, raise an error.
if "structured" in log_config and log_config.get("structured"):
raise ConfigError(STRUCTURED_ERROR)
logging.config.dictConfig(log_config)
def _reload_logging_config(log_config_path: Optional[str]) -> None:
"""
Reload the log configuration from the file and apply it.
"""
# If no log config path was given, it cannot be reloaded.
if log_config_path is None:
return
_load_logging_config(log_config_path)
logging.info("Reloaded log config from %s due to SIGHUP", log_config_path)
def setup_logging(
hs: "HomeServer",
config: "HomeServerConfig",
use_worker_options: bool = False,
logBeginner: LogBeginner = globalLogBeginner,
) -> None:
"""
Set up the logging subsystem.
Args:
config (LoggingConfig | synapse.config.worker.WorkerConfig):
configuration data
use_worker_options (bool): True to use the 'worker_log_config' option
instead of 'log_config'.
logBeginner: The Twisted logBeginner to use.
"""
log_config_path = (
config.worker.worker_log_config
if use_worker_options
else config.logging.log_config
)
# Perform one-time logging configuration.
_setup_stdlib_logging(config, log_config_path, logBeginner=logBeginner)
# Add a SIGHUP handler to reload the logging configuration, if one is available.
from synapse.app import _base as appbase
appbase.register_sighup(_reload_logging_config, log_config_path)
# Log immediately so we can grep backwards.
logging.warning("***** STARTING SERVER *****")
logging.warning(
"Server %s version %s",
sys.argv[0],
get_distribution_version_string("matrix-synapse"),
)
logging.info("Server hostname: %s", config.server.server_name)
logging.info("Instance name: %s", hs.get_instance_name())