Implemented /rooms/$roomid/state API.

synapse/handlers/message.py

@@ -232,6 +232,22 @@ class MessageHandler(BaseHandler):
         # store message in db
         yield self._on_new_room_event(event, snapshot)
 
+    @defer.inlineCallbacks
+    def get_state_events(self, user_id, room_id):
+        """Retrieve all state events for a given room.
+
+        Args:
+            user_id(str): The user requesting state events.
+            room_id(str): The room ID to get all state events from.
+        Returns:
+            A list of dicts representing state events. [{}, {}, {}]
+        """
+        yield self.auth.check_joined_room(room_id, user_id)
+
+        # TODO: This is duplicating logic from snapshot_all_rooms
+        current_state = yield self.store.get_current_state(room_id)
+        defer.returnValue([self.hs.serialize_event(c) for c in current_state])
+
     @defer.inlineCallbacks
     def snapshot_all_rooms(self, user_id=None, pagin_config=None,
                            feedback=False):

synapse/rest/room.py

@@ -329,12 +329,13 @@ class RoomStateRestServlet(RestServlet):
     @defer.inlineCallbacks
     def on_GET(self, request, room_id):
         user = yield self.auth.get_user_by_req(request)
-        # TODO: Get all the current state for this room and return in the same
-        # format as initial sync, that is:
-        # [
-        #   { state event }, { state event }
-        # ]
-        defer.returnValue((200, []))
+        handler = self.handlers.message_handler
+        # Get all the current state for this room
+        events = yield handler.get_state_events(
+            room_id=urllib.unquote(room_id),
+            user_id=user.to_string(),
+        )
+        defer.returnValue((200, events))
 
 
 # TODO: Needs unit testing