synapse-old/synapse/http/site.py

224 lines
7.5 KiB
Python

# Copyright 2016 OpenMarket 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 contextlib
import logging
import time
from twisted.web.server import Request, Site
from synapse.http import redact_uri
from synapse.http.request_metrics import RequestMetrics
from synapse.util.logcontext import ContextResourceUsage, LoggingContext
logger = logging.getLogger(__name__)
_next_request_seq = 0
class SynapseRequest(Request):
"""Class which encapsulates an HTTP request to synapse.
All of the requests processed in synapse are of this type.
It extends twisted's twisted.web.server.Request, and adds:
* Unique request ID
* Redaction of access_token query-params in __repr__
* Logging at start and end
* Metrics to record CPU, wallclock and DB time by endpoint.
It provides a method `processing` which should be called by the Resource
which is handling the request, and returns a context manager.
"""
def __init__(self, site, channel, *args, **kw):
Request.__init__(self, channel, *args, **kw)
self.site = site
self._channel = channel
self.authenticated_entity = None
self.start_time = 0
global _next_request_seq
self.request_seq = _next_request_seq
_next_request_seq += 1
def __repr__(self):
# We overwrite this so that we don't log ``access_token``
return '<%s at 0x%x method=%r uri=%r clientproto=%r site=%r>' % (
self.__class__.__name__,
id(self),
self.method,
self.get_redacted_uri(),
self.clientproto,
self.site.site_tag,
)
def get_request_id(self):
return "%s-%i" % (self.method, self.request_seq)
def get_redacted_uri(self):
return redact_uri(self.uri)
def get_user_agent(self):
return self.requestHeaders.getRawHeaders(b"User-Agent", [None])[-1]
def render(self, resrc):
# override the Server header which is set by twisted
self.setHeader("Server", self.site.server_version_string)
return Request.render(self, resrc)
def _started_processing(self, servlet_name):
self.start_time = time.time()
self.request_metrics = RequestMetrics()
self.request_metrics.start(
self.start_time, name=servlet_name, method=self.method,
)
self.site.access_logger.info(
"%s - %s - Received request: %s %s",
self.getClientIP(),
self.site.site_tag,
self.method,
self.get_redacted_uri()
)
def _finished_processing(self):
try:
context = LoggingContext.current_context()
usage = context.get_resource_usage()
except Exception:
usage = ContextResourceUsage()
end_time = time.time()
# need to decode as it could be raw utf-8 bytes
# from a IDN servname in an auth header
authenticated_entity = self.authenticated_entity
if authenticated_entity is not None:
authenticated_entity = authenticated_entity.decode("utf-8", "replace")
# ...or could be raw utf-8 bytes in the User-Agent header.
# N.B. if you don't do this, the logger explodes cryptically
# with maximum recursion trying to log errors about
# the charset problem.
# c.f. https://github.com/matrix-org/synapse/issues/3471
user_agent = self.get_user_agent()
if user_agent is not None:
user_agent = user_agent.decode("utf-8", "replace")
self.site.access_logger.info(
"%s - %s - {%s}"
" Processed request: %.3fsec (%.3fsec, %.3fsec) (%.3fsec/%.3fsec/%d)"
" %sB %s \"%s %s %s\" \"%s\" [%d dbevts]",
self.getClientIP(),
self.site.site_tag,
authenticated_entity,
end_time - self.start_time,
usage.ru_utime,
usage.ru_stime,
usage.db_sched_duration_sec,
usage.db_txn_duration_sec,
int(usage.db_txn_count),
self.sentLength,
self.code,
self.method,
self.get_redacted_uri(),
self.clientproto,
user_agent,
usage.evt_db_fetch_count,
)
try:
self.request_metrics.stop(end_time, self)
except Exception as e:
logger.warn("Failed to stop metrics: %r", e)
@contextlib.contextmanager
def processing(self, servlet_name):
"""Record the fact that we are processing this request.
Returns a context manager; the correct way to use this is:
@defer.inlineCallbacks
def handle_request(request):
with request.processing("FooServlet"):
yield really_handle_the_request()
This will log the request's arrival. Once the context manager is
closed, the completion of the request will be logged, and the various
metrics will be updated.
Args:
servlet_name (str): the name of the servlet which will be
processing this request. This is used in the metrics.
It is possible to update this afterwards by updating
self.request_metrics.servlet_name.
"""
# TODO: we should probably just move this into render() and finish(),
# to save having to call a separate method.
self._started_processing(servlet_name)
yield
self._finished_processing()
class XForwardedForRequest(SynapseRequest):
def __init__(self, *args, **kw):
SynapseRequest.__init__(self, *args, **kw)
"""
Add a layer on top of another request that only uses the value of an
X-Forwarded-For header as the result of C{getClientIP}.
"""
def getClientIP(self):
"""
@return: The client address (the first address) in the value of the
I{X-Forwarded-For header}. If the header is not present, return
C{b"-"}.
"""
return self.requestHeaders.getRawHeaders(
b"x-forwarded-for", [b"-"])[0].split(b",")[0].strip()
class SynapseRequestFactory(object):
def __init__(self, site, x_forwarded_for):
self.site = site
self.x_forwarded_for = x_forwarded_for
def __call__(self, *args, **kwargs):
if self.x_forwarded_for:
return XForwardedForRequest(self.site, *args, **kwargs)
else:
return SynapseRequest(self.site, *args, **kwargs)
class SynapseSite(Site):
"""
Subclass of a twisted http Site that does access logging with python's
standard logging
"""
def __init__(self, logger_name, site_tag, config, resource,
server_version_string, *args, **kwargs):
Site.__init__(self, resource, *args, **kwargs)
self.site_tag = site_tag
proxied = config.get("x_forwarded", False)
self.requestFactory = SynapseRequestFactory(self, proxied)
self.access_logger = logging.getLogger(logger_name)
self.server_version_string = server_version_string
def log(self, request):
pass