Fix to use milliseconds

Signed-off-by: Olivier Wilkinson (reivilibre) <olivier@librepush.net>

changelog.d/5879.misc

@@ -0,0 +1 @@
+Rework room and user statistics to separate current & historical rows, as well as track stats correctly.

synapse/config/stats.py

@@ -27,19 +27,16 @@ class StatsConfig(Config):
 
     def read_config(self, config, **kwargs):
         self.stats_enabled = True
-        self.stats_bucket_size = 86400
+        self.stats_bucket_size = 86400 * 1000
         self.stats_retention = sys.maxsize
         stats_config = config.get("stats", None)
         if stats_config:
             self.stats_enabled = stats_config.get("enabled", self.stats_enabled)
-            self.stats_bucket_size = (
-                self.parse_duration(stats_config.get("bucket_size", "1d")) / 1000
+            self.stats_bucket_size = self.parse_duration(
+                stats_config.get("bucket_size", "1d")
             )
-            self.stats_retention = (
-                self.parse_duration(
-                    stats_config.get("retention", "%ds" % (sys.maxsize,))
-                )
-                / 1000
+            self.stats_retention = self.parse_duration(
+                stats_config.get("retention", "%ds" % (sys.maxsize,))
             )
 
     def generate_config_section(self, config_dir_path, server_name, **kwargs):

synapse/handlers/stats.py

@@ -49,9 +49,6 @@ class StatsHandler(StateDeltasHandler):
         # The current position in the current_state_delta stream
         self.pos = None
 
-        # Guard to ensure we only process deltas one at a time
-        self._is_processing = False
-
         if hs.config.stats_enabled:
             self.notifier.add_replication_callback(self.notify_new_event)
 
@@ -65,43 +62,60 @@ class StatsHandler(StateDeltasHandler):
         if not self.hs.config.stats_enabled:
             return
 
-        if self._is_processing:
-            return
+        lock = self.store.stats_delta_processing_lock
 
         @defer.inlineCallbacks
         def process():
+            yield lock.acquire()
             try:
                 yield self._unsafe_process()
             finally:
-                self._is_processing = False
+                yield lock.release()
 
-        self._is_processing = True
-        run_as_background_process("stats.notify_new_event", process)
+        if not lock.locked:
+            # we only want to run this process one-at-a-time,
+            # and also, if the initial background updater wants us to keep out,
+            # we should respect that.
+            run_as_background_process("stats.notify_new_event", process)
 
     @defer.inlineCallbacks
     def _unsafe_process(self):
         # If self.pos is None then means we haven't fetched it from DB
-        if self.pos is None:
-            self.pos = yield self.store.get_stats_stream_pos()
+        # If None is one of the values, then means that the stats regenerator has not (or had not) yet unwedged us
+        #   but note that this might be outdated, so we retrieve the positions again.
+        if self.pos is None or None in self.pos.values():
+            self.pos = yield self.store.get_stats_positions()
 
-        # If still None then the initial background update hasn't happened yet
-        if self.pos is None:
+        # If still contains a None position, then the stats regenerator hasn't started yet
+        if None in self.pos.values():
             return None
 
         # Loop round handling deltas until we're up to date
+
         while True:
             with Measure(self.clock, "stats_delta"):
-                deltas = yield self.store.get_current_state_deltas(self.pos)
-                if not deltas:
-                    return
+                deltas = yield self.store.get_current_state_deltas(
+                    self.pos["state_delta_stream_id"]
+                )
 
-                logger.info("Handling %d state deltas", len(deltas))
+                logger.debug("Handling %d state deltas", len(deltas))
                 yield self._handle_deltas(deltas)
 
-                self.pos = deltas[-1]["stream_id"]
-                yield self.store.update_stats_stream_pos(self.pos)
+                self.pos["state_delta_stream_id"] = deltas[-1]["stream_id"]
+                yield self.store.update_stats_positions(self.pos)
 
-                event_processing_positions.labels("stats").set(self.pos)
+                event_processing_positions.labels("stats").set(
+                    self.pos["state_delta_stream_id"]
+                )
+
+            # Then count deltas for total_events and total_event_bytes.
+            with Measure(self.clock, "stats_total_events_and_bytes"):
+                self.pos, had_counts = yield self.store.incremental_update_room_total_events_and_bytes(
+                    self.pos
+                )
+
+            if not deltas and not had_counts:
+                break
 
     @defer.inlineCallbacks
     def _handle_deltas(self, deltas):
@@ -119,7 +133,7 @@ class StatsHandler(StateDeltasHandler):
 
             logger.debug("Handling: %r %r, %s", typ, state_key, event_id)
 
-            token = yield self.store.get_earliest_token_for_room_stats(room_id)
+            token = yield self.store.get_earliest_token_for_stats("room", room_id)
 
             # If the earliest token to begin from is larger than our current
             # stream ID, skip processing this delta.
@@ -131,7 +145,10 @@ class StatsHandler(StateDeltasHandler):
                 continue
 
             if event_id is None and prev_event_id is None:
-                # Errr...
+                logger.error(
+                    "event ID is None and so is the previous event ID. stream_id: %s",
+                    stream_id,
+                )
                 continue
 
             event_content = {}
@@ -143,92 +160,87 @@ class StatsHandler(StateDeltasHandler):
 
             # We use stream_pos here rather than fetch by event_id as event_id
             # may be None
-            now = yield self.store.get_received_ts_by_stream_pos(stream_pos)
+            stream_timestamp = yield self.store.get_received_ts_by_stream_pos(
+                stream_pos
+            )
+            stream_timestamp = int(stream_timestamp)
 
-            # quantise time to the nearest bucket
-            now = (now // 1000 // self.stats_bucket_size) * self.stats_bucket_size
+            # All the values in this dict are deltas (RELATIVE changes)
+            room_stats_delta = {}
+            is_newly_created = False
+
+            if prev_event_id is None:
+                # this state event doesn't overwrite another,
+                # so it is a new effective/current state event
+                room_stats_delta["current_state_events"] = 1
 
             if typ == EventTypes.Member:
                 # we could use _get_key_change here but it's a bit inefficient
                 # given we're not testing for a specific result; might as well
                 # just grab the prev_membership and membership strings and
                 # compare them.
-                prev_event_content = {}
+                # We take None rather than leave as a previous membership
+                # in the absence of a previous event because we do not want to
+                # reduce the leave count when a new-to-the-room user joins.
+                prev_membership = None
                 if prev_event_id is not None:
                     prev_event = yield self.store.get_event(
                         prev_event_id, allow_none=True
                     )
                     if prev_event:
                         prev_event_content = prev_event.content
+                        prev_membership = prev_event_content.get(
+                            "membership", Membership.LEAVE
+                        )
 
                 membership = event_content.get("membership", Membership.LEAVE)
-                prev_membership = prev_event_content.get("membership", Membership.LEAVE)
 
-                if prev_membership == membership:
-                    continue
-
-                if prev_membership == Membership.JOIN:
-                    yield self.store.update_stats_delta(
-                        now, "room", room_id, "joined_members", -1
-                    )
+                if prev_membership is None:
+                    logger.debug("No previous membership for this user.")
+                elif membership == prev_membership:
+                    pass  # noop
+                elif prev_membership == Membership.JOIN:
+                    room_stats_delta["joined_members"] = -1
                 elif prev_membership == Membership.INVITE:
-                    yield self.store.update_stats_delta(
-                        now, "room", room_id, "invited_members", -1
-                    )
+                    room_stats_delta["invited_members"] = -1
                 elif prev_membership == Membership.LEAVE:
-                    yield self.store.update_stats_delta(
-                        now, "room", room_id, "left_members", -1
-                    )
+                    room_stats_delta["left_members"] = -1
                 elif prev_membership == Membership.BAN:
-                    yield self.store.update_stats_delta(
-                        now, "room", room_id, "banned_members", -1
-                    )
+                    room_stats_delta["banned_members"] = -1
                 else:
-                    err = "%s is not a valid prev_membership" % (repr(prev_membership),)
-                    logger.error(err)
-                    raise ValueError(err)
+                    raise ValueError(
+                        "%r is not a valid prev_membership" % (prev_membership,)
+                    )
 
+                if membership == prev_membership:
+                    pass  # noop
                 if membership == Membership.JOIN:
-                    yield self.store.update_stats_delta(
-                        now, "room", room_id, "joined_members", +1
-                    )
+                    room_stats_delta["joined_members"] = +1
                 elif membership == Membership.INVITE:
-                    yield self.store.update_stats_delta(
-                        now, "room", room_id, "invited_members", +1
-                    )
+                    room_stats_delta["invited_members"] = +1
                 elif membership == Membership.LEAVE:
-                    yield self.store.update_stats_delta(
-                        now, "room", room_id, "left_members", +1
-                    )
+                    room_stats_delta["left_members"] = +1
                 elif membership == Membership.BAN:
-                    yield self.store.update_stats_delta(
-                        now, "room", room_id, "banned_members", +1
-                    )
+                    room_stats_delta["banned_members"] = +1
                 else:
-                    err = "%s is not a valid membership" % (repr(membership),)
-                    logger.error(err)
-                    raise ValueError(err)
+                    raise ValueError("%r is not a valid membership" % (membership,))
 
                 user_id = state_key
                 if self.is_mine_id(user_id):
-                    # update user_stats as it's one of our users
-                    public = yield self._is_public_room(room_id)
+                    # this accounts for transitions like leave → ban and so on.
+                    has_changed_joinedness = (prev_membership == Membership.JOIN) != (
+                        membership == Membership.JOIN
+                    )
+
+                    if has_changed_joinedness:
+                        # update user_stats as it's one of our users
+                        public = yield self._is_public_room(room_id)
+
+                        field = "public_rooms" if public else "private_rooms"
+                        delta = +1 if membership == Membership.JOIN else -1
 
-                    if membership == Membership.LEAVE:
                         yield self.store.update_stats_delta(
-                            now,
-                            "user",
-                            user_id,
-                            "public_rooms" if public else "private_rooms",
-                            -1,
-                        )
-                    elif membership == Membership.JOIN:
-                        yield self.store.update_stats_delta(
-                            now,
-                            "user",
-                            user_id,
-                            "public_rooms" if public else "private_rooms",
-                            +1,
+                            stream_timestamp, "user", user_id, {field: delta}
                         )
 
             elif typ == EventTypes.Create:
@@ -246,28 +258,50 @@ class StatsHandler(StateDeltasHandler):
                     },
                 )
 
+                is_newly_created = True
+
             elif typ == EventTypes.JoinRules:
+                old_room_state = yield self.store.get_room_state(room_id)
                 yield self.store.update_room_state(
                     room_id, {"join_rules": event_content.get("join_rule")}
                 )
 
-                is_public = yield self._get_key_change(
-                    prev_event_id, event_id, "join_rule", JoinRules.PUBLIC
+                # whether the room would be public anyway,
+                # because of history_visibility
+                other_field_gives_publicity = (
+                    old_room_state["history_visibility"] == "world_readable"
                 )
-                if is_public is not None:
-                    yield self.update_public_room_stats(now, room_id, is_public)
+
+                if not other_field_gives_publicity:
+                    is_public = yield self._get_key_change(
+                        prev_event_id, event_id, "join_rule", JoinRules.PUBLIC
+                    )
+                    if is_public is not None:
+                        yield self.update_public_room_stats(
+                            stream_timestamp, room_id, is_public
+                        )
 
             elif typ == EventTypes.RoomHistoryVisibility:
+                old_room_state = yield self.store.get_room_state(room_id)
                 yield self.store.update_room_state(
                     room_id,
                     {"history_visibility": event_content.get("history_visibility")},
                 )
 
-                is_public = yield self._get_key_change(
-                    prev_event_id, event_id, "history_visibility", "world_readable"
+                # whether the room would be public anyway,
+                # because of join_rule
+                other_field_gives_publicity = (
+                    old_room_state["join_rules"] == JoinRules.PUBLIC
                 )
-                if is_public is not None:
-                    yield self.update_public_room_stats(now, room_id, is_public)
+
+                if not other_field_gives_publicity:
+                    is_public = yield self._get_key_change(
+                        prev_event_id, event_id, "history_visibility", "world_readable"
+                    )
+                    if is_public is not None:
+                        yield self.update_public_room_stats(
+                            stream_timestamp, room_id, is_public
+                        )
 
             elif typ == EventTypes.Encryption:
                 yield self.store.update_room_state(
@@ -290,6 +324,20 @@ class StatsHandler(StateDeltasHandler):
                     room_id, {"canonical_alias": event_content.get("alias")}
                 )
 
+            if is_newly_created:
+                yield self.store.update_stats_delta(
+                    stream_timestamp,
+                    "room",
+                    room_id,
+                    room_stats_delta,
+                    complete_with_stream_id=stream_id,
+                )
+
+            elif len(room_stats_delta) > 0:
+                yield self.store.update_stats_delta(
+                    stream_timestamp, "room", room_id, room_stats_delta
+                )
+
     @defer.inlineCallbacks
     def update_public_room_stats(self, ts, room_id, is_public):
         """
@@ -308,10 +356,13 @@ class StatsHandler(StateDeltasHandler):
         for user_id in user_ids:
             if self.hs.is_mine(UserID.from_string(user_id)):
                 yield self.store.update_stats_delta(
-                    ts, "user", user_id, "public_rooms", +1 if is_public else -1
-                )
-                yield self.store.update_stats_delta(
-                    ts, "user", user_id, "private_rooms", -1 if is_public else +1
+                    ts,
+                    "user",
+                    user_id,
+                    {
+                        "public_rooms": +1 if is_public else -1,
+                        "private_rooms": -1 if is_public else +1,
+                    },
                 )
 
     @defer.inlineCallbacks

synapse/storage/events.py

@@ -2270,8 +2270,9 @@ class EventsStore(
             "room_aliases",
             "room_depth",
             "room_memberships",
-            "room_state",
-            "room_stats",
+            "room_stats_state",
+            "room_stats_current",
+            "room_stats_historical",
             "room_stats_earliest_token",
             "rooms",
             "stream_ordering_to_exterm",

synapse/storage/schema/delta/56/stats_separated1.sql

@@ -0,0 +1,144 @@
+/* Copyright 2018 New Vector Ltd
+ * Copyright 2019 The Matrix.org Foundation C.I.C.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+
+----- First clean up from previous versions of room stats.
+
+-- First remove old stats stuff
+DROP TABLE IF EXISTS room_stats;
+DROP TABLE IF EXISTS user_stats;
+DROP TABLE IF EXISTS room_stats_earliest_tokens;
+DROP TABLE IF EXISTS _temp_populate_stats_position;
+DROP TABLE IF EXISTS _temp_populate_stats_rooms;
+DROP TABLE IF EXISTS stats_stream_pos;
+
+-- Unschedule old background updates if they're still scheduled
+DELETE FROM background_updates WHERE update_name IN (
+    'populate_stats_createtables',
+    'populate_stats_process_rooms',
+    'populate_stats_cleanup'
+);
+
+----- Create tables for our version of room stats.
+
+-- single-row table to track position of incremental updates
+CREATE TABLE IF NOT EXISTS stats_incremental_position (
+    -- the stream_id of the last-processed state delta
+    state_delta_stream_id BIGINT,
+
+    -- the stream_ordering of the last-processed backfilled event
+    -- (this is negative)
+    total_events_min_stream_ordering BIGINT,
+
+    -- the stream_ordering of the last-processed normally-created event
+    -- (this is positive)
+    total_events_max_stream_ordering BIGINT,
+
+    -- If true, this represents the contract agreed upon by the stats
+    -- regenerator.
+    -- If false, this is suitable for use by the delta/incremental processor.
+    is_background_contract BOOLEAN NOT NULL PRIMARY KEY
+);
+
+-- insert a null row and make sure it is the only one.
+DELETE FROM stats_incremental_position;
+INSERT INTO stats_incremental_position (
+    state_delta_stream_id,
+    total_events_min_stream_ordering,
+    total_events_max_stream_ordering,
+    is_background_contract
+) VALUES (NULL, NULL, NULL, (0 = 1)), (NULL, NULL, NULL, (1 = 1));
+
+-- represents PRESENT room statistics for a room
+-- only holds absolute fields
+CREATE TABLE IF NOT EXISTS room_stats_current (
+    room_id TEXT NOT NULL PRIMARY KEY,
+
+    current_state_events INT NOT NULL,
+    total_events INT NOT NULL,
+    total_event_bytes BIGINT NOT NULL,
+    joined_members INT NOT NULL,
+    invited_members INT NOT NULL,
+    left_members INT NOT NULL,
+    banned_members INT NOT NULL,
+
+    -- If initial stats regen is still to be performed: NULL
+    -- If initial stats regen has been performed: the maximum delta stream
+    --  position that this row takes into account.
+    completed_delta_stream_id BIGINT
+);
+
+
+-- represents HISTORICAL room statistics for a room
+CREATE TABLE IF NOT EXISTS room_stats_historical (
+    room_id TEXT NOT NULL,
+    -- These stats cover the time from (end_ts - bucket_size)...end_ts (in ms).
+    -- Note that end_ts is quantised.
+    end_ts BIGINT NOT NULL,
+    bucket_size INT NOT NULL,
+
+    current_state_events INT NOT NULL,
+    total_events INT NOT NULL,
+    total_event_bytes BIGINT NOT NULL,
+    joined_members INT NOT NULL,
+    invited_members INT NOT NULL,
+    left_members INT NOT NULL,
+    banned_members INT NOT NULL,
+
+    PRIMARY KEY (room_id, end_ts)
+);
+
+-- We use this index to speed up deletion of ancient room stats.
+CREATE INDEX IF NOT EXISTS room_stats_historical_end_ts ON room_stats_historical (end_ts);
+
+-- We don't need an index on (room_id, end_ts) because PRIMARY KEY sorts that
+-- out for us. (We would want it to review stats for a particular room.)
+
+
+-- represents PRESENT statistics for a user
+-- only holds absolute fields
+CREATE TABLE IF NOT EXISTS user_stats_current (
+    user_id TEXT NOT NULL PRIMARY KEY,
+
+    public_rooms INT NOT NULL,
+    private_rooms INT NOT NULL,
+
+    -- If initial stats regen is still to be performed: NULL
+    -- If initial stats regen has been performed: the maximum delta stream
+    --  position that this row takes into account.
+    completed_delta_stream_id BIGINT
+);
+
+-- represents HISTORICAL statistics for a user
+CREATE TABLE IF NOT EXISTS user_stats_historical (
+    user_id TEXT NOT NULL,
+    end_ts BIGINT NOT NULL,
+    bucket_size INT NOT NULL,
+
+    public_rooms INT NOT NULL,
+    private_rooms INT NOT NULL,
+
+    PRIMARY KEY (user_id, end_ts)
+);
+
+-- We use this index to speed up deletion of ancient user stats.
+CREATE INDEX IF NOT EXISTS user_stats_historical_end_ts ON user_stats_historical (end_ts);
+
+-- We don't need an index on (user_id, end_ts) because PRIMARY KEY sorts that
+-- out for us. (We would want it to review stats for a particular user.)
+
+-- Also rename room_state to room_stats_state to make its ownership clear.
+ALTER TABLE room_state RENAME TO room_stats_state;

synapse/storage/schema/delta/56/stats_separated2.sql.postgres

@@ -0,0 +1,24 @@
+/* Copyright 2019 The Matrix.org Foundation C.I.C.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+-- These partial indices helps us with finding incomplete stats row
+CREATE INDEX IF NOT EXISTS room_stats_not_complete
+    ON room_stats_current (room_id)
+    WHERE completed_delta_stream_id IS NULL;
+
+CREATE INDEX IF NOT EXISTS user_stats_not_complete
+    ON user_stats_current (user_id)
+    WHERE completed_delta_stream_id IS NULL;
+

synapse/storage/schema/delta/56/stats_separated2.sql.sqlite

@@ -0,0 +1,27 @@
+/* Copyright 2019 The Matrix.org Foundation C.I.C.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+-- even though SQLite >= 3.8 can support partial indices, we won't enable
+-- them, in case the SQLite database may be later used on another system.
+-- It's also the case that SQLite is only likely to be used in small
+-- deployments or testing, where the optimisations gained by use of a
+-- partial index are not a big concern.
+
+CREATE INDEX IF NOT EXISTS room_stats_not_complete
+    ON room_stats_current (completed_delta_stream_id, room_id);
+
+CREATE INDEX IF NOT EXISTS user_stats_not_complete
+    ON user_stats_current (completed_delta_stream_id, user_id);
+

tests/handlers/test_stats.py

@@ -1,304 +0,0 @@
-# -*- coding: utf-8 -*-
-# Copyright 2019 New Vector Ltd
-#
-# Licensed under the Apache License, Version 2.0 (the "License");
-# you may not use this file except in compliance with the License.
-# You may obtain a copy of the License at
-#
-#     http://www.apache.org/licenses/LICENSE-2.0
-#
-# Unless required by applicable law or agreed to in writing, software
-# distributed under the License is distributed on an "AS IS" BASIS,
-# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-# See the License for the specific language governing permissions and
-# limitations under the License.
-
-from mock import Mock
-
-from twisted.internet import defer
-
-from synapse.api.constants import EventTypes, Membership
-from synapse.rest import admin
-from synapse.rest.client.v1 import login, room
-
-from tests import unittest
-
-
-class StatsRoomTests(unittest.HomeserverTestCase):
-
-    servlets = [
-        admin.register_servlets_for_client_rest_resource,
-        room.register_servlets,
-        login.register_servlets,
-    ]
-
-    def prepare(self, reactor, clock, hs):
-
-        self.store = hs.get_datastore()
-        self.handler = self.hs.get_stats_handler()
-
-    def _add_background_updates(self):
-        """
-        Add the background updates we need to run.
-        """
-        # Ugh, have to reset this flag
-        self.store._all_done = False
-
-        self.get_success(
-            self.store._simple_insert(
-                "background_updates",
-                {"update_name": "populate_stats_createtables", "progress_json": "{}"},
-            )
-        )
-        self.get_success(
-            self.store._simple_insert(
-                "background_updates",
-                {
-                    "update_name": "populate_stats_process_rooms",
-                    "progress_json": "{}",
-                    "depends_on": "populate_stats_createtables",
-                },
-            )
-        )
-        self.get_success(
-            self.store._simple_insert(
-                "background_updates",
-                {
-                    "update_name": "populate_stats_cleanup",
-                    "progress_json": "{}",
-                    "depends_on": "populate_stats_process_rooms",
-                },
-            )
-        )
-
-    def test_initial_room(self):
-        """
-        The background updates will build the table from scratch.
-        """
-        r = self.get_success(self.store.get_all_room_state())
-        self.assertEqual(len(r), 0)
-
-        # Disable stats
-        self.hs.config.stats_enabled = False
-        self.handler.stats_enabled = False
-
-        u1 = self.register_user("u1", "pass")
-        u1_token = self.login("u1", "pass")
-
-        room_1 = self.helper.create_room_as(u1, tok=u1_token)
-        self.helper.send_state(
-            room_1, event_type="m.room.topic", body={"topic": "foo"}, tok=u1_token
-        )
-
-        # Stats disabled, shouldn't have done anything
-        r = self.get_success(self.store.get_all_room_state())
-        self.assertEqual(len(r), 0)
-
-        # Enable stats
-        self.hs.config.stats_enabled = True
-        self.handler.stats_enabled = True
-
-        # Do the initial population of the user directory via the background update
-        self._add_background_updates()
-
-        while not self.get_success(self.store.has_completed_background_updates()):
-            self.get_success(self.store.do_next_background_update(100), by=0.1)
-
-        r = self.get_success(self.store.get_all_room_state())
-
-        self.assertEqual(len(r), 1)
-        self.assertEqual(r[0]["topic"], "foo")
-
-    def test_initial_earliest_token(self):
-        """
-        Ingestion via notify_new_event will ignore tokens that the background
-        update have already processed.
-        """
-        self.reactor.advance(86401)
-
-        self.hs.config.stats_enabled = False
-        self.handler.stats_enabled = False
-
-        u1 = self.register_user("u1", "pass")
-        u1_token = self.login("u1", "pass")
-
-        u2 = self.register_user("u2", "pass")
-        u2_token = self.login("u2", "pass")
-
-        u3 = self.register_user("u3", "pass")
-        u3_token = self.login("u3", "pass")
-
-        room_1 = self.helper.create_room_as(u1, tok=u1_token)
-        self.helper.send_state(
-            room_1, event_type="m.room.topic", body={"topic": "foo"}, tok=u1_token
-        )
-
-        # Begin the ingestion by creating the temp tables. This will also store
-        # the position that the deltas should begin at, once they take over.
-        self.hs.config.stats_enabled = True
-        self.handler.stats_enabled = True
-        self.store._all_done = False
-        self.get_success(self.store.update_stats_stream_pos(None))
-
-        self.get_success(
-            self.store._simple_insert(
-                "background_updates",
-                {"update_name": "populate_stats_createtables", "progress_json": "{}"},
-            )
-        )
-
-        while not self.get_success(self.store.has_completed_background_updates()):
-            self.get_success(self.store.do_next_background_update(100), by=0.1)
-
-        # Now, before the table is actually ingested, add some more events.
-        self.helper.invite(room=room_1, src=u1, targ=u2, tok=u1_token)
-        self.helper.join(room=room_1, user=u2, tok=u2_token)
-
-        # Now do the initial ingestion.
-        self.get_success(
-            self.store._simple_insert(
-                "background_updates",
-                {"update_name": "populate_stats_process_rooms", "progress_json": "{}"},
-            )
-        )
-        self.get_success(
-            self.store._simple_insert(
-                "background_updates",
-                {
-                    "update_name": "populate_stats_cleanup",
-                    "progress_json": "{}",
-                    "depends_on": "populate_stats_process_rooms",
-                },
-            )
-        )
-
-        self.store._all_done = False
-        while not self.get_success(self.store.has_completed_background_updates()):
-            self.get_success(self.store.do_next_background_update(100), by=0.1)
-
-        self.reactor.advance(86401)
-
-        # Now add some more events, triggering ingestion. Because of the stream
-        # position being set to before the events sent in the middle, a simpler
-        # implementation would reprocess those events, and say there were four
-        # users, not three.
-        self.helper.invite(room=room_1, src=u1, targ=u3, tok=u1_token)
-        self.helper.join(room=room_1, user=u3, tok=u3_token)
-
-        # Get the deltas! There should be two -- day 1, and day 2.
-        r = self.get_success(self.store.get_deltas_for_room(room_1, 0))
-
-        # The oldest has 2 joined members
-        self.assertEqual(r[-1]["joined_members"], 2)
-
-        # The newest has 3
-        self.assertEqual(r[0]["joined_members"], 3)
-
-    def test_incorrect_state_transition(self):
-        """
-        If the state transition is not one of (JOIN, INVITE, LEAVE, BAN) to
-        (JOIN, INVITE, LEAVE, BAN), an error is raised.
-        """
-        events = {
-            "a1": {"membership": Membership.LEAVE},
-            "a2": {"membership": "not a real thing"},
-        }
-
-        def get_event(event_id, allow_none=True):
-            m = Mock()
-            m.content = events[event_id]
-            d = defer.Deferred()
-            self.reactor.callLater(0.0, d.callback, m)
-            return d
-
-        def get_received_ts(event_id):
-            return defer.succeed(1)
-
-        self.store.get_received_ts = get_received_ts
-        self.store.get_event = get_event
-
-        deltas = [
-            {
-                "type": EventTypes.Member,
-                "state_key": "some_user",
-                "room_id": "room",
-                "event_id": "a1",
-                "prev_event_id": "a2",
-                "stream_id": 60,
-            }
-        ]
-
-        f = self.get_failure(self.handler._handle_deltas(deltas), ValueError)
-        self.assertEqual(
-            f.value.args[0], "'not a real thing' is not a valid prev_membership"
-        )
-
-        # And the other way...
-        deltas = [
-            {
-                "type": EventTypes.Member,
-                "state_key": "some_user",
-                "room_id": "room",
-                "event_id": "a2",
-                "prev_event_id": "a1",
-                "stream_id": 100,
-            }
-        ]
-
-        f = self.get_failure(self.handler._handle_deltas(deltas), ValueError)
-        self.assertEqual(
-            f.value.args[0], "'not a real thing' is not a valid membership"
-        )
-
-    def test_redacted_prev_event(self):
-        """
-        If the prev_event does not exist, then it is assumed to be a LEAVE.
-        """
-        u1 = self.register_user("u1", "pass")
-        u1_token = self.login("u1", "pass")
-
-        room_1 = self.helper.create_room_as(u1, tok=u1_token)
-
-        # Do the initial population of the user directory via the background update
-        self._add_background_updates()
-
-        while not self.get_success(self.store.has_completed_background_updates()):
-            self.get_success(self.store.do_next_background_update(100), by=0.1)
-
-        events = {"a1": None, "a2": {"membership": Membership.JOIN}}
-
-        def get_event(event_id, allow_none=True):
-            if events.get(event_id):
-                m = Mock()
-                m.content = events[event_id]
-            else:
-                m = None
-            d = defer.Deferred()
-            self.reactor.callLater(0.0, d.callback, m)
-            return d
-
-        def get_received_ts(event_id):
-            return defer.succeed(1)
-
-        self.store.get_received_ts = get_received_ts
-        self.store.get_event = get_event
-
-        deltas = [
-            {
-                "type": EventTypes.Member,
-                "state_key": "some_user:test",
-                "room_id": room_1,
-                "event_id": "a2",
-                "prev_event_id": "a1",
-                "stream_id": 100,
-            }
-        ]
-
-        # Handle our fake deltas, which has a user going from LEAVE -> JOIN.
-        self.get_success(self.handler._handle_deltas(deltas))
-
-        # One delta, with two joined members -- the room creator, and our fake
-        # user.
-        r = self.get_success(self.store.get_deltas_for_room(room_1, 0))
-        self.assertEqual(len(r), 1)
-        self.assertEqual(r[0]["joined_members"], 2)