Add user_may_send_state_event callback to spam checker module API (#18455)

tests/module_api/test_spamchecker.py

@@ -153,3 +153,92 @@ class SpamCheckerTestCase(HomeserverTestCase):
         channel = self.create_room({"foo": "baa"})
         self.assertEqual(channel.code, 200)
         self.assertEqual(self.last_user_id, self.user_id)
+
+    def test_user_may_send_state_event(self) -> None:
+        """Test that the user_may_send_state_event callback is called when a state event
+        is sent, and that it receives the correct parameters.
+        """
+
+        async def user_may_send_state_event(
+            user_id: str,
+            room_id: str,
+            event_type: str,
+            state_key: str,
+            content: JsonDict,
+        ) -> Union[Literal["NOT_SPAM"], Codes]:
+            self.last_user_id = user_id
+            self.last_room_id = room_id
+            self.last_event_type = event_type
+            self.last_state_key = state_key
+            self.last_content = content
+            return "NOT_SPAM"
+
+        self._module_api.register_spam_checker_callbacks(
+            user_may_send_state_event=user_may_send_state_event
+        )
+
+        channel = self.create_room({})
+        self.assertEqual(channel.code, 200)
+
+        room_id = channel.json_body["room_id"]
+
+        event_type = "test.event.type"
+        state_key = "test.state.key"
+        channel = self.make_request(
+            "PUT",
+            "/_matrix/client/r0/rooms/%s/state/%s/%s"
+            % (
+                room_id,
+                event_type,
+                state_key,
+            ),
+            content={"foo": "bar"},
+            access_token=self.token,
+        )
+
+        self.assertEqual(channel.code, 200)
+        self.assertEqual(self.last_user_id, self.user_id)
+        self.assertEqual(self.last_room_id, room_id)
+        self.assertEqual(self.last_event_type, event_type)
+        self.assertEqual(self.last_state_key, state_key)
+        self.assertEqual(self.last_content, {"foo": "bar"})
+
+    def test_user_may_send_state_event_disallows(self) -> None:
+        """Test that the user_may_send_state_event callback is called when a state event
+        is sent, and that the response is honoured.
+        """
+
+        async def user_may_send_state_event(
+            user_id: str,
+            room_id: str,
+            event_type: str,
+            state_key: str,
+            content: JsonDict,
+        ) -> Union[Literal["NOT_SPAM"], Codes]:
+            return Codes.FORBIDDEN
+
+        self._module_api.register_spam_checker_callbacks(
+            user_may_send_state_event=user_may_send_state_event
+        )
+
+        channel = self.create_room({})
+        self.assertEqual(channel.code, 200)
+
+        room_id = channel.json_body["room_id"]
+
+        event_type = "test.event.type"
+        state_key = "test.state.key"
+        channel = self.make_request(
+            "PUT",
+            "/_matrix/client/r0/rooms/%s/state/%s/%s"
+            % (
+                room_id,
+                event_type,
+                state_key,
+            ),
+            content={"foo": "bar"},
+            access_token=self.token,
+        )
+
+        self.assertEqual(channel.code, 403)
+        self.assertEqual(channel.json_body["errcode"], Codes.FORBIDDEN)