Merge pull request #1802 from matrix-org/erikj/remove_debug_deferreds

Remove full_twisted_stacktraces option

synapse/config/logger.py

@@ -22,7 +22,6 @@ import yaml
 from string import Template
 import os
 import signal
-from synapse.util.debug import debug_deferreds
 
 
 DEFAULT_LOG_CONFIG = Template("""
@@ -71,8 +70,6 @@ class LoggingConfig(Config):
         self.verbosity = config.get("verbose", 0)
         self.log_config = self.abspath(config.get("log_config"))
         self.log_file = self.abspath(config.get("log_file"))
-        if config.get("full_twisted_stacktraces"):
-            debug_deferreds()
 
     def default_config(self, config_dir_path, server_name, **kwargs):
         log_file = self.abspath("homeserver.log")
@@ -88,11 +85,6 @@ class LoggingConfig(Config):
 
         # A yaml python logging config file
         log_config: "%(log_config)s"
-
-        # Stop twisted from discarding the stack traces of exceptions in
-        # deferreds by waiting a reactor tick before running a deferred's
-        # callbacks.
-        # full_twisted_stacktraces: true
         """ % locals()
 
     def read_arguments(self, args):

synapse/util/debug.py

@@ -1,71 +0,0 @@
-# -*- coding: utf-8 -*-
-# Copyright 2015, 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.
-
-from twisted.internet import defer, reactor
-from functools import wraps
-from synapse.util.logcontext import LoggingContext, PreserveLoggingContext
-
-
-def debug_deferreds():
-    """Cause all deferreds to wait for a reactor tick before running their
-    callbacks. This increases the chance of getting a stack trace out of
-    a defer.inlineCallback since the code waiting on the deferred will get
-    a chance to add an errback before the deferred runs."""
-
-    # Helper method for retrieving and restoring the current logging context
-    # around a callback.
-    def with_logging_context(fn):
-        context = LoggingContext.current_context()
-
-        def restore_context_callback(x):
-            with PreserveLoggingContext(context):
-                return fn(x)
-
-        return restore_context_callback
-
-    # We are going to modify the __init__ method of defer.Deferred so we
-    # need to get a copy of the old method so we can still call it.
-    old__init__ = defer.Deferred.__init__
-
-    # We need to create a deferred to bounce the callbacks through the reactor
-    # but we don't want to add a callback when we create that deferred so we
-    # we create a new type of deferred that uses the old __init__ method.
-    # This is safe as long as the old __init__ method doesn't invoke an
-    # __init__ using super.
-    class Bouncer(defer.Deferred):
-        __init__ = old__init__
-
-    # We'll add this as a callback to all Deferreds. Twisted will wait until
-    # the bouncer deferred resolves before calling the callbacks of the
-    # original deferred.
-    def bounce_callback(x):
-        bouncer = Bouncer()
-        reactor.callLater(0, with_logging_context(bouncer.callback), x)
-        return bouncer
-
-    # We'll add this as an errback to all Deferreds. Twisted will wait until
-    # the bouncer deferred resolves before calling the errbacks of the
-    # original deferred.
-    def bounce_errback(x):
-        bouncer = Bouncer()
-        reactor.callLater(0, with_logging_context(bouncer.errback), x)
-        return bouncer
-
-    @wraps(old__init__)
-    def new__init__(self, *args, **kargs):
-        old__init__(self, *args, **kargs)
-        self.addCallbacks(bounce_callback, bounce_errback)
-
-    defer.Deferred.__init__ = new__init__