279 lines
9.4 KiB
Python
279 lines
9.4 KiB
Python
# -*- coding: utf-8 -*-
|
|
# Copyright 2019 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.
|
|
|
|
"""
|
|
Log formatters that output terse JSON.
|
|
"""
|
|
|
|
import sys
|
|
from collections import deque
|
|
from ipaddress import IPv4Address, IPv6Address, ip_address
|
|
from math import floor
|
|
from typing.io import TextIO
|
|
|
|
import attr
|
|
from simplejson import dumps
|
|
|
|
from twisted.application.internet import ClientService
|
|
from twisted.internet.endpoints import (
|
|
HostnameEndpoint,
|
|
TCP4ClientEndpoint,
|
|
TCP6ClientEndpoint,
|
|
)
|
|
from twisted.internet.protocol import Factory, Protocol
|
|
from twisted.logger import FileLogObserver, Logger
|
|
from twisted.python.failure import Failure
|
|
|
|
|
|
def flatten_event(event: dict, metadata: dict, include_time: bool = False):
|
|
"""
|
|
Flatten a Twisted logging event to an dictionary capable of being sent
|
|
as a log event to a logging aggregation system.
|
|
|
|
The format is vastly simplified and is not designed to be a "human readable
|
|
string" in the sense that traditional logs are. Instead, the structure is
|
|
optimised for searchability and filtering, with human-understandable log
|
|
keys.
|
|
|
|
Args:
|
|
event (dict): The Twisted logging event we are flattening.
|
|
metadata (dict): Additional data to include with each log message. This
|
|
can be information like the server name. Since the target log
|
|
consumer does not know who we are other than by host IP, this
|
|
allows us to forward through static information.
|
|
include_time (bool): Should we include the `time` key? If False, the
|
|
event time is stripped from the event.
|
|
"""
|
|
new_event = {}
|
|
|
|
# If it's a failure, make the new event's log_failure be the traceback text.
|
|
if "log_failure" in event:
|
|
new_event["log_failure"] = event["log_failure"].getTraceback()
|
|
|
|
# If it's a warning, copy over a string representation of the warning.
|
|
if "warning" in event:
|
|
new_event["warning"] = str(event["warning"])
|
|
|
|
# Stdlib logging events have "log_text" as their human-readable portion,
|
|
# Twisted ones have "log_format". For now, include the log_format, so that
|
|
# context only given in the log format (e.g. what is being logged) is
|
|
# available.
|
|
if "log_text" in event:
|
|
new_event["log"] = event["log_text"]
|
|
else:
|
|
new_event["log"] = event["log_format"]
|
|
|
|
# We want to include the timestamp when forwarding over the network, but
|
|
# exclude it when we are writing to stdout. This is because the log ingester
|
|
# (e.g. logstash, fluentd) can add its own timestamp.
|
|
if include_time:
|
|
new_event["time"] = round(event["log_time"], 2)
|
|
|
|
# Convert the log level to a textual representation.
|
|
new_event["level"] = event["log_level"].name.upper()
|
|
|
|
# Ignore these keys, and do not transfer them over to the new log object.
|
|
# They are either useless (isError), transferred manually above (log_time,
|
|
# log_level, etc), or contain Python objects which are not useful for output
|
|
# (log_logger, log_source).
|
|
keys_to_delete = [
|
|
"isError",
|
|
"log_failure",
|
|
"log_format",
|
|
"log_level",
|
|
"log_logger",
|
|
"log_source",
|
|
"log_system",
|
|
"log_time",
|
|
"log_text",
|
|
"observer",
|
|
"warning",
|
|
]
|
|
|
|
# If it's from the Twisted legacy logger (twisted.python.log), it adds some
|
|
# more keys we want to purge.
|
|
if event.get("log_namespace") == "log_legacy":
|
|
keys_to_delete.extend(["message", "system", "time"])
|
|
|
|
# Rather than modify the dictionary in place, construct a new one with only
|
|
# the content we want. The original event should be considered 'frozen'.
|
|
for key in event.keys():
|
|
|
|
if key in keys_to_delete:
|
|
continue
|
|
|
|
if isinstance(event[key], (str, int, bool, float)) or event[key] is None:
|
|
# If it's a plain type, include it as is.
|
|
new_event[key] = event[key]
|
|
else:
|
|
# If it's not one of those basic types, write out a string
|
|
# representation. This should probably be a warning in development,
|
|
# so that we are sure we are only outputting useful data.
|
|
new_event[key] = str(event[key])
|
|
|
|
# Add the metadata information to the event (e.g. the server_name).
|
|
new_event.update(metadata)
|
|
|
|
return new_event
|
|
|
|
|
|
def TerseJSONToConsoleLogObserver(outFile: TextIO, metadata: dict) -> FileLogObserver:
|
|
"""
|
|
A log observer that formats events to a flattened JSON representation.
|
|
|
|
Args:
|
|
outFile: The file object to write to.
|
|
metadata: Metadata to be added to each log object.
|
|
"""
|
|
|
|
def formatEvent(_event: dict) -> str:
|
|
flattened = flatten_event(_event, metadata)
|
|
return dumps(flattened, ensure_ascii=False, separators=(",", ":")) + "\n"
|
|
|
|
return FileLogObserver(outFile, formatEvent)
|
|
|
|
|
|
@attr.s
|
|
class TerseJSONToTCPLogObserver(object):
|
|
"""
|
|
An IObserver that writes JSON logs to a TCP target.
|
|
|
|
Args:
|
|
hs (HomeServer): The Homeserver that is being logged for.
|
|
host: The host of the logging target.
|
|
port: The logging target's port.
|
|
metadata: Metadata to be added to each log entry.
|
|
"""
|
|
|
|
hs = attr.ib()
|
|
host = attr.ib(type=str)
|
|
port = attr.ib(type=int)
|
|
metadata = attr.ib(type=dict)
|
|
maximum_buffer = attr.ib(type=int)
|
|
_buffer = attr.ib(default=attr.Factory(deque), type=deque)
|
|
_writer = attr.ib(default=None)
|
|
_logger = attr.ib(default=attr.Factory(Logger))
|
|
|
|
def start(self) -> None:
|
|
|
|
# Connect without DNS lookups if it's a direct IP.
|
|
try:
|
|
ip = ip_address(self.host)
|
|
if isinstance(ip, IPv4Address):
|
|
endpoint = TCP4ClientEndpoint(
|
|
self.hs.get_reactor(), self.host, self.port
|
|
)
|
|
elif isinstance(ip, IPv6Address):
|
|
endpoint = TCP6ClientEndpoint(
|
|
self.hs.get_reactor(), self.host, self.port
|
|
)
|
|
except ValueError:
|
|
endpoint = HostnameEndpoint(self.hs.get_reactor(), self.host, self.port)
|
|
|
|
factory = Factory.forProtocol(Protocol)
|
|
self._service = ClientService(endpoint, factory, clock=self.hs.get_reactor())
|
|
self._service.startService()
|
|
|
|
def _write_loop(self) -> None:
|
|
"""
|
|
Implement the write loop.
|
|
"""
|
|
if self._writer:
|
|
return
|
|
|
|
self._writer = self._service.whenConnected()
|
|
|
|
@self._writer.addBoth
|
|
def writer(r):
|
|
if isinstance(r, Failure):
|
|
r.printTraceback(file=sys.__stderr__)
|
|
self._writer = None
|
|
self.hs.get_reactor().callLater(1, self._write_loop)
|
|
return
|
|
|
|
try:
|
|
for event in self._buffer:
|
|
r.transport.write(
|
|
dumps(event, ensure_ascii=False, separators=(",", ":")).encode(
|
|
"utf8"
|
|
)
|
|
)
|
|
r.transport.write(b"\n")
|
|
self._buffer.clear()
|
|
except Exception as e:
|
|
sys.__stderr__.write("Failed writing out logs with %s\n" % (str(e),))
|
|
|
|
self._writer = False
|
|
self.hs.get_reactor().callLater(1, self._write_loop)
|
|
|
|
def _handle_pressure(self) -> None:
|
|
"""
|
|
Handle backpressure by shedding events.
|
|
|
|
The buffer will, in this order, until the buffer is below the maximum:
|
|
- Shed DEBUG events
|
|
- Shed INFO events
|
|
- Shed the middle 50% of the events.
|
|
"""
|
|
if len(self._buffer) <= self.maximum_buffer:
|
|
return
|
|
|
|
# Strip out DEBUGs
|
|
self._buffer = deque(
|
|
filter(lambda event: event["level"] != "DEBUG", self._buffer)
|
|
)
|
|
|
|
if len(self._buffer) <= self.maximum_buffer:
|
|
return
|
|
|
|
# Strip out INFOs
|
|
self._buffer = deque(
|
|
filter(lambda event: event["level"] != "INFO", self._buffer)
|
|
)
|
|
|
|
if len(self._buffer) <= self.maximum_buffer:
|
|
return
|
|
|
|
# Cut the middle entries out
|
|
buffer_split = floor(self.maximum_buffer / 2)
|
|
|
|
old_buffer = self._buffer
|
|
self._buffer = deque()
|
|
|
|
for i in range(buffer_split):
|
|
self._buffer.append(old_buffer.popleft())
|
|
|
|
end_buffer = []
|
|
for i in range(buffer_split):
|
|
end_buffer.append(old_buffer.pop())
|
|
|
|
self._buffer.extend(reversed(end_buffer))
|
|
|
|
def __call__(self, event: dict) -> None:
|
|
flattened = flatten_event(event, self.metadata, include_time=True)
|
|
self._buffer.append(flattened)
|
|
|
|
# Handle backpressure, if it exists.
|
|
try:
|
|
self._handle_pressure()
|
|
except Exception:
|
|
# If handling backpressure fails,clear the buffer and log the
|
|
# exception.
|
|
self._buffer.clear()
|
|
self._logger.failure("Failed clearing backpressure")
|
|
|
|
# Try and write immediately.
|
|
self._write_loop()
|