Remove unused get_prev_events_and_hashes_for_room

synapse/storage/data_stores/main/event_federation.py

@@ -14,7 +14,6 @@
 # limitations under the License.
 import itertools
 import logging
-import random
 
 from six.moves import range
 from six.moves.queue import Empty, PriorityQueue
@@ -148,35 +147,6 @@ class EventFederationWorkerStore(EventsWorkerStore, SignatureWorkerStore, SQLBas
             retcol="event_id",
         )
 
-    @defer.inlineCallbacks
-    def get_prev_events_and_hashes_for_room(self, room_id):
-        """
-        Gets a subset of the current forward extremities in the given room,
-        along with their depths and hashes.
-
-        Limits the result to 10 extremities, so that we can avoid creating
-        events which refer to hundreds of prev_events.
-
-        Args:
-            room_id (str): room_id
-
-        Returns:
-            Deferred[list[(str, dict[str, str], int)]]
-                for each event, a tuple of (event_id, hashes, depth)
-                where *hashes* is a map from algorithm to hash.
-        """
-        res = yield self.get_latest_event_ids_and_hashes_in_room(room_id)
-        if len(res) > 10:
-            # Sort by reverse depth, so we point to the most recent.
-            res.sort(key=lambda a: -a[2])
-
-            # we use half of the limit for the actual most recent events, and
-            # the other half to randomly point to some of the older events, to
-            # make sure that we don't completely ignore the older events.
-            res = res[0:5] + random.sample(res[5:], 5)
-
-        return res
-
     def get_prev_events_for_room(self, room_id: str):
         """
         Gets a subset of the current forward extremities in the given room.

tests/storage/test_event_federation.py

@@ -26,7 +26,7 @@ class EventFederationWorkerStoreTestCase(tests.unittest.TestCase):
         self.store = hs.get_datastore()
 
     @defer.inlineCallbacks
-    def test_get_prev_events_and_hashes_for_room(self):
+    def test_get_prev_events_for_room(self):
         room_id = "@ROOM:local"
 
         # add a bunch of events and hashes to act as forward extremities
@@ -60,21 +60,14 @@ class EventFederationWorkerStoreTestCase(tests.unittest.TestCase):
                 (event_id, bytearray(b"ffff")),
             )
 
-        for i in range(0, 11):
+        for i in range(0, 20):
             yield self.store.db.runInteraction("insert", insert_event, i)
 
-        # this should get the last five and five others
-        r = yield self.store.get_prev_events_and_hashes_for_room(room_id)
+        # this should get the last ten
+        r = yield self.store.get_prev_events_for_room(room_id)
         self.assertEqual(10, len(r))
-        for i in range(0, 5):
-            el = r[i]
-            depth = el[2]
-            self.assertEqual(10 - i, depth)
-
-        for i in range(5, 5):
-            el = r[i]
-            depth = el[2]
-            self.assertLessEqual(5, depth)
+        for i in range(0, 10):
+            self.assertEqual("$event_%i:local" % (19 - i), r[i])
 
     @defer.inlineCallbacks
     def test_get_rooms_with_many_extremities(self):