From 3d3da2b4609d02bbbb276313fd6b2cc8069e213d Mon Sep 17 00:00:00 2001
From: Mark Haines <mark.haines@matrix.org>
Date: Tue, 1 Dec 2015 16:03:08 +0000
Subject: [PATCH 1/4] Only fire user_joined_room on the distributor if the user
 has actually joined the room

---
 synapse/handlers/room.py | 10 ++++++----
 1 file changed, 6 insertions(+), 4 deletions(-)

diff --git a/synapse/handlers/room.py b/synapse/handlers/room.py
index 023b4001b..cb6ac3775 100644
--- a/synapse/handlers/room.py
+++ b/synapse/handlers/room.py
@@ -517,10 +517,12 @@ class RoomMemberHandler(BaseHandler):
                 do_auth=do_auth,
             )
 
-        user = UserID.from_string(event.user_id)
-        yield self.distributor.fire(
-            "user_joined_room", user=user, room_id=room_id
-        )
+        prev_state = context.current_state.get((event.type, event.state_key))
+        if not prev_state or prev_state.membership != Membership.JOIN:
+            user = UserID.from_string(event.user_id)
+            yield self.distributor.fire(
+                "user_joined_room", user=user, room_id=room_id
+            )
 
     @defer.inlineCallbacks
     def get_inviter(self, event):

From ed0f79bdc5e507705655fa380394b8f4328f90e1 Mon Sep 17 00:00:00 2001
From: Mark Haines <mark.haines@matrix.org>
Date: Tue, 1 Dec 2015 19:46:15 +0000
Subject: [PATCH 2/4] Only fire user_joined_room if the membership has changed

---
 synapse/handlers/federation.py | 11 ++++++++---
 1 file changed, 8 insertions(+), 3 deletions(-)

diff --git a/synapse/handlers/federation.py b/synapse/handlers/federation.py
index c1bce07e3..e5fb1dd3c 100644
--- a/synapse/handlers/federation.py
+++ b/synapse/handlers/federation.py
@@ -233,10 +233,15 @@ class FederationHandler(BaseHandler):
 
         if event.type == EventTypes.Member:
             if event.membership == Membership.JOIN:
-                user = UserID.from_string(event.state_key)
-                yield self.distributor.fire(
-                    "user_joined_room", user=user, room_id=event.room_id
+                context = yield self.state_handler.compute_event_context(
+                    event, old_state=state, outlier=event.internal_metadata.is_outlier()
                 )
+                prev_state = context.current_state.get((event.type, event.state_key))
+                if not prev_state or prev_state.membership != Membership.JOIN:
+                    user = UserID.from_string(event.state_key)
+                    yield self.distributor.fire(
+                        "user_joined_room", user=user, room_id=event.room_id
+                    )
 
     @defer.inlineCallbacks
     def _filter_events_for_server(self, server_name, room_id, events):

From c30cdb0d6881a3f463574043637072b71d1a3ab2 Mon Sep 17 00:00:00 2001
From: Mark Haines <mark.haines@matrix.org>
Date: Wed, 2 Dec 2015 10:49:35 +0000
Subject: [PATCH 3/4] Add comments

---
 synapse/handlers/federation.py | 3 +++
 synapse/handlers/room.py       | 3 +++
 2 files changed, 6 insertions(+)

diff --git a/synapse/handlers/federation.py b/synapse/handlers/federation.py
index a03a5f494..5f3562b5b 100644
--- a/synapse/handlers/federation.py
+++ b/synapse/handlers/federation.py
@@ -239,6 +239,9 @@ class FederationHandler(BaseHandler):
                 )
                 prev_state = context.current_state.get((event.type, event.state_key))
                 if not prev_state or prev_state.membership != Membership.JOIN:
+                    # Only fire user_joined_room if the user has acutally
+                    # joined the room. Don't bother if the user is just
+                    # changing their profile info.
                     user = UserID.from_string(event.state_key)
                     yield user_joined_room(self.distributor, user, event.room_id)
 
diff --git a/synapse/handlers/room.py b/synapse/handlers/room.py
index 1e18038e1..116a998c4 100644
--- a/synapse/handlers/room.py
+++ b/synapse/handlers/room.py
@@ -527,6 +527,9 @@ class RoomMemberHandler(BaseHandler):
 
         prev_state = context.current_state.get((event.type, event.state_key))
         if not prev_state or prev_state.membership != Membership.JOIN:
+            # Only fire user_joined_room if the user has acutally joined the
+            # room. Don't bother if the user is just changing their profile
+            # info.
             user = UserID.from_string(event.user_id)
             yield user_joined_room(self.distributor, user, room_id)
 

From c2c70f7daf5ea1b638e7366f57570417155ab7e2 Mon Sep 17 00:00:00 2001
From: Mark Haines <mark.haines@matrix.org>
Date: Wed, 2 Dec 2015 12:01:24 +0000
Subject: [PATCH 4/4] Use the context returned by _handle_new_event

---
 synapse/handlers/federation.py | 5 +----
 1 file changed, 1 insertion(+), 4 deletions(-)

diff --git a/synapse/handlers/federation.py b/synapse/handlers/federation.py
index 5f3562b5b..2855f2d7c 100644
--- a/synapse/handlers/federation.py
+++ b/synapse/handlers/federation.py
@@ -177,7 +177,7 @@ class FederationHandler(BaseHandler):
                 )
 
             try:
-                _, event_stream_id, max_stream_id = yield self._handle_new_event(
+                context, event_stream_id, max_stream_id = yield self._handle_new_event(
                     origin,
                     event,
                     state=state,
@@ -234,9 +234,6 @@ class FederationHandler(BaseHandler):
 
         if event.type == EventTypes.Member:
             if event.membership == Membership.JOIN:
-                context = yield self.state_handler.compute_event_context(
-                    event, old_state=state, outlier=event.internal_metadata.is_outlier()
-                )
                 prev_state = context.current_state.get((event.type, event.state_key))
                 if not prev_state or prev_state.membership != Membership.JOIN:
                     # Only fire user_joined_room if the user has acutally