Move RequestMetrics handling into SynapseRequest.processing()

It fits quite nicely here, and opens the path to getting rid of the
"include_metrics" mess.
pull/3203/head
Richard van der Hoff 2018-05-09 23:05:14 +01:00
parent 09b29f9c4a
commit c6f730282c
2 changed files with 64 additions and 24 deletions

View File

@ -19,7 +19,7 @@ from synapse.api.errors import (
cs_exception, SynapseError, CodeMessageException, UnrecognizedRequestError, Codes
)
from synapse.http.request_metrics import (
RequestMetrics, requests_counter,
requests_counter,
outgoing_responses_counter,
)
from synapse.util.logcontext import LoggingContext, PreserveLoggingContext
@ -81,19 +81,18 @@ def wrap_request_handler(request_handler, include_metrics=False):
with LoggingContext(request_id) as request_context:
request_context.request = request_id
with Measure(self.clock, "wrapped_request_handler"):
request_metrics = RequestMetrics()
# we start the request metrics timer here with an initial stab
# at the servlet name. For most requests that name will be
# JsonResource (or a subclass), and JsonResource._async_render
# will update it once it picks a servlet.
servlet_name = self.__class__.__name__
request_metrics.start(self.clock.time_msec(), name=servlet_name)
with request.processing():
with request.processing(servlet_name):
try:
with PreserveLoggingContext(request_context):
if include_metrics:
yield request_handler(self, request, request_metrics)
yield request_handler(
self, request, request.request_metrics,
)
else:
requests_counter.inc(request.method, servlet_name)
yield request_handler(self, request)
@ -135,13 +134,7 @@ def wrap_request_handler(request_handler, include_metrics=False):
pretty_print=_request_user_agent_is_curl(request),
version_string=self.version_string,
)
finally:
try:
request_metrics.stop(
self.clock.time_msec(), request
)
except Exception as e:
logger.warn("Failed to stop metrics: %r", e)
return wrapped_request_handler

View File

@ -12,20 +12,38 @@
# See the License for the specific language governing permissions and
# limitations under the License.
from synapse.util.logcontext import LoggingContext
from twisted.web.server import Site, Request
import contextlib
import logging
import re
import time
from twisted.web.server import Site, Request
from synapse.http.request_metrics import RequestMetrics
from synapse.util.logcontext import LoggingContext
logger = logging.getLogger(__name__)
ACCESS_TOKEN_RE = re.compile(br'(\?.*access(_|%5[Ff])token=)[^&]*(.*)$')
_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, *args, **kw):
Request.__init__(self, *args, **kw)
self.site = site
@ -59,7 +77,11 @@ class SynapseRequest(Request):
def get_user_agent(self):
return self.requestHeaders.getRawHeaders(b"User-Agent", [None])[-1]
def started_processing(self):
def _started_processing(self, servlet_name):
self.start_time = int(time.time() * 1000)
self.request_metrics = RequestMetrics()
self.request_metrics.start(self.start_time, name=servlet_name)
self.site.access_logger.info(
"%s - %s - Received request: %s %s",
self.getClientIP(),
@ -67,10 +89,8 @@ class SynapseRequest(Request):
self.method,
self.get_redacted_uri()
)
self.start_time = int(time.time() * 1000)
def finished_processing(self):
def _finished_processing(self):
try:
context = LoggingContext.current_context()
ru_utime, ru_stime = context.get_resource_usage()
@ -81,6 +101,8 @@ class SynapseRequest(Request):
ru_utime, ru_stime = (0, 0)
db_txn_count, db_txn_duration_ms = (0, 0)
end_time = int(time.time() * 1000)
self.site.access_logger.info(
"%s - %s - {%s}"
" Processed request: %dms (%dms, %dms) (%dms/%dms/%d)"
@ -88,7 +110,7 @@ class SynapseRequest(Request):
self.getClientIP(),
self.site.site_tag,
self.authenticated_entity,
int(time.time() * 1000) - self.start_time,
end_time - self.start_time,
int(ru_utime * 1000),
int(ru_stime * 1000),
db_sched_duration_ms,
@ -102,11 +124,36 @@ class SynapseRequest(Request):
self.get_user_agent(),
)
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):
self.started_processing()
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.
"""
self._started_processing(servlet_name)
yield
self.finished_processing()
self._finished_processing()
class XForwardedForRequest(SynapseRequest):