Add a module API method to retrieve state from a room

changelog.d/11204.feature

@@ -0,0 +1 @@
+Add a module API method to retrieve the current state of a room.

synapse/module_api/__init__.py

@@ -54,6 +54,7 @@
     DomainSpecificString,
     JsonDict,
     Requester,
+    StateMap,
     UserID,
     UserInfo,
     create_requester,
@@ -866,6 +867,19 @@ async def get_user_ip_and_agents(
         else:
             return []
 
+    async def get_room_state(self, room_id: str) -> StateMap[EventBase]:
+        """Returns the current state of the given room.
+
+        The events are returned as a mapping, in which the key for each event is a tuple
+        which first element is the event's type and the second one is its state key.
+
+        Added in Synapse v1.47.0
+        """
+        state_ids = await self._store.get_current_state_ids(room_id)
+        state_events = await self._store.get_events(state_ids.values())
+
+        return {key: state_events[event_id] for key, event_id in state_ids.items()}
+
 
 class PublicRoomListManager:
     """Contains methods for adding to, removing from and querying whether a room

tests/module_api/test_api.py

@@ -15,7 +15,7 @@
 
 from twisted.internet import defer
 
-from synapse.api.constants import EduTypes
+from synapse.api.constants import EduTypes, EventTypes
 from synapse.events import EventBase
 from synapse.federation.units import Transaction
 from synapse.handlers.presence import UserPresenceState
@@ -385,6 +385,27 @@ def test_send_local_online_presence_to_federation(self):
 
         self.assertTrue(found_update)
 
+    def test_get_room_state(self):
+        """Tests that a module can retrieve the state of a room through the module API."""
+        user_id = self.register_user("peter", "hackme")
+        tok = self.login("peter", "hackme")
+
+        # Create a room and send some custom state in it.
+        room_id = self.helper.create_room_as(tok=tok)
+        self.helper.send_state(room_id, "org.matrix.test", {}, tok=tok)
+
+        # Check that the module API can successfully fetch state for the room.
+        state = self.get_success(
+            defer.ensureDeferred(self.module_api.get_room_state(room_id))
+        )
+
+        # Check that a few standard events are in the returned state.
+        self.assertIn((EventTypes.Create, ""), state)
+        self.assertIn((EventTypes.Member, user_id), state)
+
+        # Check that our custom state event is in the returned state.
+        self.assertIn(("org.matrix.test", ""), state)
+
 
 class ModuleApiWorkerTestCase(BaseMultiWorkerStreamTestCase):
     """For testing ModuleApi functionality in a multi-worker setup"""