Move all the wrapper functions for distributor.fire

Move the functions inside the distributor and import them
where needed. This reduces duplication and makes it possible
for flake8 to detect when the functions aren't used in a
given file.

synapse/handlers/federation.py

@@ -40,6 +40,7 @@ from synapse.events.utils import prune_event
 from synapse.util.retryutils import NotRetryingDestination
 
 from synapse.push.action_generator import ActionGenerator
+from synapse.util.distributor import user_joined_room
 
 from twisted.internet import defer
 
@@ -49,10 +50,6 @@ import logging
 logger = logging.getLogger(__name__)
 
 
-def user_joined_room(distributor, user, room_id):
-    return distributor.fire("user_joined_room", user, room_id)
-
-
 class FederationHandler(BaseHandler):
     """Handles events that originated from federation.
         Responsible for:

synapse/handlers/register.py

@@ -23,6 +23,7 @@ from synapse.api.errors import (
 from ._base import BaseHandler
 from synapse.util.async import run_on_reactor
 from synapse.http.client import CaptchaServerHttpClient
+from synapse.util.distributor import registered_user
 
 import logging
 import urllib
@@ -30,10 +31,6 @@ import urllib
 logger = logging.getLogger(__name__)
 
 
-def registered_user(distributor, user):
-    return distributor.fire("registered_user", user)
-
-
 class RegistrationHandler(BaseHandler):
 
     def __init__(self, hs):

synapse/handlers/room.py

@@ -25,7 +25,6 @@ from synapse.api.constants import (
 from synapse.api.errors import AuthError, StoreError, SynapseError
 from synapse.util import stringutils
 from synapse.util.async import concurrently_execute
-from synapse.util.logcontext import preserve_context_over_fn
 from synapse.util.caches.response_cache import ResponseCache
 
 from collections import OrderedDict
@@ -39,20 +38,6 @@ logger = logging.getLogger(__name__)
 id_server_scheme = "https://"
 
 
-def user_left_room(distributor, user, room_id):
-    return preserve_context_over_fn(
-        distributor.fire,
-        "user_left_room", user=user, room_id=room_id
-    )
-
-
-def user_joined_room(distributor, user, room_id):
-    return preserve_context_over_fn(
-        distributor.fire,
-        "user_joined_room", user=user, room_id=room_id
-    )
-
-
 class RoomCreationHandler(BaseHandler):
 
     PRESETS_DICT = {

synapse/handlers/room_member.py

@@ -23,8 +23,8 @@ from synapse.api.constants import (
     EventTypes, Membership,
 )
 from synapse.api.errors import AuthError, SynapseError, Codes
-from synapse.util.logcontext import preserve_context_over_fn
 from synapse.util.async import Linearizer
+from synapse.util.distributor import user_left_room, user_joined_room
 
 from signedjson.sign import verify_signed_json
 from signedjson.key import decode_verify_key_bytes
@@ -38,20 +38,6 @@ logger = logging.getLogger(__name__)
 id_server_scheme = "https://"
 
 
-def user_left_room(distributor, user, room_id):
-    return preserve_context_over_fn(
-        distributor.fire,
-        "user_left_room", user=user, room_id=room_id
-    )
-
-
-def user_joined_room(distributor, user, room_id):
-    return preserve_context_over_fn(
-        distributor.fire,
-        "user_joined_room", user=user, room_id=room_id
-    )
-
-
 class RoomMemberHandler(BaseHandler):
     # TODO(paul): This handler currently contains a messy conflation of
     #   low-level API that works on UserID objects and so on, and REST-level

synapse/util/distributor.py

@@ -15,7 +15,9 @@
 
 from twisted.internet import defer
 
-from synapse.util.logcontext import PreserveLoggingContext
+from synapse.util.logcontext import (
+    PreserveLoggingContext, preserve_context_over_fn
+)
 
 from synapse.util import unwrapFirstError
 
@@ -25,6 +27,24 @@ import logging
 logger = logging.getLogger(__name__)
 
 
+def registered_user(distributor, user):
+    return distributor.fire("registered_user", user)
+
+
+def user_left_room(distributor, user, room_id):
+    return preserve_context_over_fn(
+        distributor.fire,
+        "user_left_room", user=user, room_id=room_id
+    )
+
+
+def user_joined_room(distributor, user, room_id):
+    return preserve_context_over_fn(
+        distributor.fire,
+        "user_joined_room", user=user, room_id=room_id
+    )
+
+
 class Distributor(object):
     """A central dispatch point for loosely-connected pieces of code to
     register, observe, and fire signals.