# Copyright 2015 OpenMarket Ltd # Copyright 2018 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. """Responsible for storing and fetching push actions / notifications. There are two main uses for push actions: 1. Sending out push to a user's device; and 2. Tracking per-room per-user notification counts (used in sync requests). For the former we simply use the `event_push_actions` table, which contains all the calculated actions for a given user (which were calculated by the `BulkPushRuleEvaluator`). For the latter we could simply count the number of rows in `event_push_actions` table for a given room/user, but in practice this is *very* heavyweight when there were a large number of notifications (due to e.g. the user never reading a room). Plus, keeping all push actions indefinitely uses a lot of disk space. To fix these issues, we add a new table `event_push_summary` that tracks per-user per-room counts of all notifications that happened before a stream ordering S. Thus, to get the notification count for a user / room we can simply query a single row in `event_push_summary` and count the number of rows in `event_push_actions` with a stream ordering larger than S (and as long as S is "recent", the number of rows needing to be scanned will be small). The `event_push_summary` table is updated via a background job that periodically chooses a new stream ordering S' (usually the latest stream ordering), counts all notifications in `event_push_actions` between the existing S and S', and adds them to the existing counts in `event_push_summary`. This allows us to delete old rows from `event_push_actions` once those rows have been counted and added to `event_push_summary` (we call this process "rotation"). We need to handle when a user sends a read receipt to the room. Again this is done as a background process. For each receipt we clear the row in `event_push_summary` and count the number of notifications in `event_push_actions` that happened after the receipt but before S, and insert that count into `event_push_summary` (If the receipt happened *after* S then we simply clear the `event_push_summary`.) Note that its possible that if the read receipt is for an old event the relevant `event_push_actions` rows will have been rotated and we get the wrong count (it'll be too low). We accept this as a rare edge case that is unlikely to impact the user much (since the vast majority of read receipts will be for the latest event). The last complication is to handle the race where we request the notifications counts after a user sends a read receipt into the room, but *before* the background update handles the receipt (without any special handling the counts would be outdated). We fix this by including in `event_push_summary` the read receipt we used when updating `event_push_summary`, and every time we query the table we check if that matches the most recent read receipt in the room. If yes, continue as above, if not we simply query the `event_push_actions` table directly. Since read receipts are almost always for recent events, scanning the `event_push_actions` table in this case is unlikely to be a problem. Even if it is a problem, it is temporary until the background job handles the new read receipt. """ import logging from typing import ( TYPE_CHECKING, Collection, Dict, List, Mapping, Optional, Tuple, Union, cast, ) import attr from synapse.api.constants import ReceiptTypes from synapse.metrics.background_process_metrics import wrap_as_background_process from synapse.storage._base import SQLBaseStore, db_to_json, make_in_list_sql_clause from synapse.storage.database import ( DatabasePool, LoggingDatabaseConnection, LoggingTransaction, ) from synapse.storage.databases.main.receipts import ReceiptsWorkerStore from synapse.storage.databases.main.stream import StreamWorkerStore from synapse.types import JsonDict from synapse.util import json_encoder from synapse.util.caches.descriptors import cached if TYPE_CHECKING: from synapse.server import HomeServer logger = logging.getLogger(__name__) DEFAULT_NOTIF_ACTION: List[Union[dict, str]] = [ "notify", {"set_tweak": "highlight", "value": False}, ] DEFAULT_HIGHLIGHT_ACTION: List[Union[dict, str]] = [ "notify", {"set_tweak": "sound", "value": "default"}, {"set_tweak": "highlight"}, ] @attr.s(slots=True, frozen=True, auto_attribs=True) class HttpPushAction: """ HttpPushAction instances include the information used to generate HTTP requests to a push gateway. """ event_id: str room_id: str stream_ordering: int actions: List[Union[dict, str]] @attr.s(slots=True, frozen=True, auto_attribs=True) class EmailPushAction(HttpPushAction): """ EmailPushAction instances include the information used to render an email push notification. """ received_ts: Optional[int] @attr.s(slots=True, frozen=True, auto_attribs=True) class UserPushAction(EmailPushAction): """ UserPushAction instances include the necessary information to respond to /notifications requests. """ topological_ordering: int highlight: bool profile_tag: str @attr.s(slots=True, auto_attribs=True) class NotifCounts: """ The per-user, per-room count of notifications. Used by sync and push. """ notify_count: int = 0 unread_count: int = 0 highlight_count: int = 0 def _serialize_action( actions: Collection[Union[Mapping, str]], is_highlight: bool ) -> str: """Custom serializer for actions. This allows us to "compress" common actions. We use the fact that most users have the same actions for notifs (and for highlights). We store these default actions as the empty string rather than the full JSON. Since the empty string isn't valid JSON there is no risk of this clashing with any real JSON actions """ if is_highlight: if actions == DEFAULT_HIGHLIGHT_ACTION: return "" # We use empty string as the column is non-NULL else: if actions == DEFAULT_NOTIF_ACTION: return "" return json_encoder.encode(actions) def _deserialize_action(actions: str, is_highlight: bool) -> List[Union[dict, str]]: """Custom deserializer for actions. This allows us to "compress" common actions""" if actions: return db_to_json(actions) if is_highlight: return DEFAULT_HIGHLIGHT_ACTION else: return DEFAULT_NOTIF_ACTION class EventPushActionsWorkerStore(ReceiptsWorkerStore, StreamWorkerStore, SQLBaseStore): def __init__( self, database: DatabasePool, db_conn: LoggingDatabaseConnection, hs: "HomeServer", ): super().__init__(database, db_conn, hs) # These get correctly set by _find_stream_orderings_for_times_txn self.stream_ordering_month_ago: Optional[int] = None self.stream_ordering_day_ago: Optional[int] = None cur = db_conn.cursor(txn_name="_find_stream_orderings_for_times_txn") self._find_stream_orderings_for_times_txn(cur) cur.close() self.find_stream_orderings_looping_call = self._clock.looping_call( self._find_stream_orderings_for_times, 10 * 60 * 1000 ) self._rotate_count = 10000 self._doing_notif_rotation = False if hs.config.worker.run_background_tasks: self._rotate_notif_loop = self._clock.looping_call( self._rotate_notifs, 30 * 1000 ) self.db_pool.updates.register_background_index_update( "event_push_summary_unique_index", index_name="event_push_summary_unique_index", table="event_push_summary", columns=["user_id", "room_id"], unique=True, replaces_index="event_push_summary_user_rm", ) self.db_pool.updates.register_background_index_update( "event_push_summary_unique_index2", index_name="event_push_summary_unique_index2", table="event_push_summary", columns=["user_id", "room_id", "thread_id"], unique=True, ) self.db_pool.updates.register_background_update_handler( "event_push_backfill_thread_id", self._background_backfill_thread_id, ) async def _background_backfill_thread_id( self, progress: JsonDict, batch_size: int ) -> int: """ Fill in the thread_id field for event_push_actions and event_push_summary. This is preparatory so that it can be made non-nullable in the future. Because all current (null) data is done in an unthreaded manner this simply assumes it is on the "main" timeline. Since event_push_actions are periodically cleared it is not possible to correctly re-calculate the thread_id. """ event_push_actions_done = progress.get("event_push_actions_done", False) def add_thread_id_txn( txn: LoggingTransaction, table_name: str, start_stream_ordering: int ) -> int: sql = f""" SELECT stream_ordering FROM {table_name} WHERE thread_id IS NULL AND stream_ordering > ? ORDER BY stream_ordering LIMIT ? """ txn.execute(sql, (start_stream_ordering, batch_size)) # No more rows to process. rows = txn.fetchall() if not rows: progress[f"{table_name}_done"] = True self.db_pool.updates._background_update_progress_txn( txn, "event_push_backfill_thread_id", progress ) return 0 # Update the thread ID for any of those rows. max_stream_ordering = rows[-1][0] sql = f""" UPDATE {table_name} SET thread_id = 'main' WHERE stream_ordering <= ? AND thread_id IS NULL """ txn.execute(sql, (max_stream_ordering,)) # Update progress. processed_rows = txn.rowcount progress[f"max_{table_name}_stream_ordering"] = max_stream_ordering self.db_pool.updates._background_update_progress_txn( txn, "event_push_backfill_thread_id", progress ) return processed_rows # First update the event_push_actions table, then the event_push_summary table. # # Note that the event_push_actions_staging table is ignored since it is # assumed that items in that table will only exist for a short period of # time. if not event_push_actions_done: result = await self.db_pool.runInteraction( "event_push_backfill_thread_id", add_thread_id_txn, "event_push_actions", progress.get("max_event_push_actions_stream_ordering", 0), ) else: result = await self.db_pool.runInteraction( "event_push_backfill_thread_id", add_thread_id_txn, "event_push_summary", progress.get("max_event_push_summary_stream_ordering", 0), ) # Only done after the event_push_summary table is done. if not result: await self.db_pool.updates._end_background_update( "event_push_backfill_thread_id" ) return result @cached(tree=True, max_entries=5000) async def get_unread_event_push_actions_by_room_for_user( self, room_id: str, user_id: str, ) -> NotifCounts: """Get the notification count, the highlight count and the unread message count for a given user in a given room after their latest read receipt. Note that this function assumes the user to be a current member of the room, since it's either called by the sync handler to handle joined room entries, or by the HTTP pusher to calculate the badge of unread joined rooms. Args: room_id: The room to retrieve the counts in. user_id: The user to retrieve the counts for. Returns A NotifCounts object containing the notification count, the highlight count and the unread message count. """ return await self.db_pool.runInteraction( "get_unread_event_push_actions_by_room", self._get_unread_counts_by_receipt_txn, room_id, user_id, ) def _get_unread_counts_by_receipt_txn( self, txn: LoggingTransaction, room_id: str, user_id: str, ) -> NotifCounts: # Get the stream ordering of the user's latest receipt in the room. result = self.get_last_receipt_for_user_txn( txn, user_id, room_id, receipt_types=( ReceiptTypes.READ, ReceiptTypes.READ_PRIVATE, ), ) if result: _, stream_ordering = result else: # If the user has no receipts in the room, retrieve the stream ordering for # the latest membership event from this user in this room (which we assume is # a join). event_id = self.db_pool.simple_select_one_onecol_txn( txn=txn, table="local_current_membership", keyvalues={"room_id": room_id, "user_id": user_id}, retcol="event_id", ) stream_ordering = self.get_stream_id_for_event_txn(txn, event_id) return self._get_unread_counts_by_pos_txn( txn, room_id, user_id, stream_ordering ) def _get_unread_counts_by_pos_txn( self, txn: LoggingTransaction, room_id: str, user_id: str, receipt_stream_ordering: int, ) -> NotifCounts: """Get the number of unread messages for a user/room that have happened since the given stream ordering. Args: txn: The database transaction. room_id: The room ID to get unread counts for. user_id: The user ID to get unread counts for. receipt_stream_ordering: The stream ordering of the user's latest receipt in the room. If there are no receipts, the stream ordering of the user's join event. Returns A NotifCounts object containing the notification count, the highlight count and the unread message count. """ counts = NotifCounts() # First we pull the counts from the summary table. # # We check that `last_receipt_stream_ordering` matches the stream # ordering given. If it doesn't match then a new read receipt has arrived and # we haven't yet updated the counts in `event_push_summary` to reflect # that; in that case we simply ignore `event_push_summary` counts # and do a manual count of all of the rows in the `event_push_actions` table # for this user/room. # # If `last_receipt_stream_ordering` is null then that means it's up to # date (as the row was written by an older version of Synapse that # updated `event_push_summary` synchronously when persisting a new read # receipt). txn.execute( """ SELECT stream_ordering, notif_count, COALESCE(unread_count, 0) FROM event_push_summary WHERE room_id = ? AND user_id = ? AND ( (last_receipt_stream_ordering IS NULL AND stream_ordering > ?) OR last_receipt_stream_ordering = ? ) """, (room_id, user_id, receipt_stream_ordering, receipt_stream_ordering), ) row = txn.fetchone() summary_stream_ordering = 0 if row: summary_stream_ordering = row[0] counts.notify_count += row[1] counts.unread_count += row[2] # Next we need to count highlights, which aren't summarised sql = """ SELECT COUNT(*) FROM event_push_actions WHERE user_id = ? AND room_id = ? AND stream_ordering > ? AND highlight = 1 """ txn.execute(sql, (user_id, room_id, receipt_stream_ordering)) row = txn.fetchone() if row: counts.highlight_count += row[0] # Finally we need to count push actions that aren't included in the # summary returned above. This might be due to recent events that haven't # been summarised yet or the summary is out of date due to a recent read # receipt. start_unread_stream_ordering = max( receipt_stream_ordering, summary_stream_ordering ) notify_count, unread_count = self._get_notif_unread_count_for_user_room( txn, room_id, user_id, start_unread_stream_ordering ) counts.notify_count += notify_count counts.unread_count += unread_count return counts def _get_notif_unread_count_for_user_room( self, txn: LoggingTransaction, room_id: str, user_id: str, stream_ordering: int, max_stream_ordering: Optional[int] = None, ) -> Tuple[int, int]: """Returns the notify and unread counts from `event_push_actions` for the given user/room in the given range. Does not consult `event_push_summary` table, which may include push actions that have been deleted from `event_push_actions` table. Args: txn: The database transaction. room_id: The room ID to get unread counts for. user_id: The user ID to get unread counts for. stream_ordering: The (exclusive) minimum stream ordering to consider. max_stream_ordering: The (inclusive) maximum stream ordering to consider. If this is not given, then no maximum is applied. Return: A tuple of the notif count and unread count in the given range. """ # If there have been no events in the room since the stream ordering, # there can't be any push actions either. if not self._events_stream_cache.has_entity_changed(room_id, stream_ordering): return 0, 0 clause = "" args = [user_id, room_id, stream_ordering] if max_stream_ordering is not None: clause = "AND ea.stream_ordering <= ?" args.append(max_stream_ordering) # If the max stream ordering is less than the min stream ordering, # then obviously there are zero push actions in that range. if max_stream_ordering <= stream_ordering: return 0, 0 sql = f""" SELECT COUNT(CASE WHEN notif = 1 THEN 1 END), COUNT(CASE WHEN unread = 1 THEN 1 END) FROM event_push_actions ea WHERE user_id = ? AND room_id = ? AND ea.stream_ordering > ? {clause} """ txn.execute(sql, args) row = txn.fetchone() if row: return cast(Tuple[int, int], row) return 0, 0 async def get_push_action_users_in_range( self, min_stream_ordering: int, max_stream_ordering: int ) -> List[str]: def f(txn: LoggingTransaction) -> List[str]: sql = ( "SELECT DISTINCT(user_id) FROM event_push_actions WHERE" " stream_ordering >= ? AND stream_ordering <= ? AND notif = 1" ) txn.execute(sql, (min_stream_ordering, max_stream_ordering)) return [r[0] for r in txn] return await self.db_pool.runInteraction("get_push_action_users_in_range", f) def _get_receipts_by_room_txn( self, txn: LoggingTransaction, user_id: str ) -> Dict[str, int]: """ Generate a map of room ID to the latest stream ordering that has been read by the given user. Args: txn: user_id: The user to fetch receipts for. Returns: A map of room ID to stream ordering for all rooms the user has a receipt in. """ receipt_types_clause, args = make_in_list_sql_clause( self.database_engine, "receipt_type", ( ReceiptTypes.READ, ReceiptTypes.READ_PRIVATE, ), ) sql = f""" SELECT room_id, MAX(stream_ordering) FROM receipts_linearized INNER JOIN events USING (room_id, event_id) WHERE {receipt_types_clause} AND user_id = ? GROUP BY room_id """ args.extend((user_id,)) txn.execute(sql, args) return { room_id: latest_stream_ordering for room_id, latest_stream_ordering in txn.fetchall() } async def get_unread_push_actions_for_user_in_range_for_http( self, user_id: str, min_stream_ordering: int, max_stream_ordering: int, limit: int = 20, ) -> List[HttpPushAction]: """Get a list of the most recent unread push actions for a given user, within the given stream ordering range. Called by the httppusher. Args: user_id: The user to fetch push actions for. min_stream_ordering: The exclusive lower bound on the stream ordering of event push actions to fetch. max_stream_ordering: The inclusive upper bound on the stream ordering of event push actions to fetch. limit: The maximum number of rows to return. Returns: A list of dicts with the keys "event_id", "room_id", "stream_ordering", "actions". The list will be ordered by ascending stream_ordering. The list will have between 0~limit entries. """ receipts_by_room = await self.db_pool.runInteraction( "get_unread_push_actions_for_user_in_range_http_receipts", self._get_receipts_by_room_txn, user_id=user_id, ) def get_push_actions_txn( txn: LoggingTransaction, ) -> List[Tuple[str, str, int, str, bool]]: sql = """ SELECT ep.event_id, ep.room_id, ep.stream_ordering, ep.actions, ep.highlight FROM event_push_actions AS ep WHERE ep.user_id = ? AND ep.stream_ordering > ? AND ep.stream_ordering <= ? AND ep.notif = 1 ORDER BY ep.stream_ordering ASC LIMIT ? """ txn.execute(sql, (user_id, min_stream_ordering, max_stream_ordering, limit)) return cast(List[Tuple[str, str, int, str, bool]], txn.fetchall()) push_actions = await self.db_pool.runInteraction( "get_unread_push_actions_for_user_in_range_http", get_push_actions_txn ) notifs = [ HttpPushAction( event_id=event_id, room_id=room_id, stream_ordering=stream_ordering, actions=_deserialize_action(actions, highlight), ) for event_id, room_id, stream_ordering, actions, highlight in push_actions # Only include push actions with a stream ordering after any receipt, or without any # receipt present (invited to but never read rooms). if stream_ordering > receipts_by_room.get(room_id, 0) ] # Now sort it so it's ordered correctly, since currently it will # contain results from the first query, correctly ordered, followed # by results from the second query, but we want them all ordered # by stream_ordering, oldest first. notifs.sort(key=lambda r: r.stream_ordering) # Take only up to the limit. We have to stop at the limit because # one of the subqueries may have hit the limit. return notifs[:limit] async def get_unread_push_actions_for_user_in_range_for_email( self, user_id: str, min_stream_ordering: int, max_stream_ordering: int, limit: int = 20, ) -> List[EmailPushAction]: """Get a list of the most recent unread push actions for a given user, within the given stream ordering range. Called by the emailpusher Args: user_id: The user to fetch push actions for. min_stream_ordering: The exclusive lower bound on the stream ordering of event push actions to fetch. max_stream_ordering: The inclusive upper bound on the stream ordering of event push actions to fetch. limit: The maximum number of rows to return. Returns: A list of dicts with the keys "event_id", "room_id", "stream_ordering", "actions", "received_ts". The list will be ordered by descending received_ts. The list will have between 0~limit entries. """ receipts_by_room = await self.db_pool.runInteraction( "get_unread_push_actions_for_user_in_range_email_receipts", self._get_receipts_by_room_txn, user_id=user_id, ) def get_push_actions_txn( txn: LoggingTransaction, ) -> List[Tuple[str, str, int, str, bool, int]]: sql = """ SELECT ep.event_id, ep.room_id, ep.stream_ordering, ep.actions, ep.highlight, e.received_ts FROM event_push_actions AS ep INNER JOIN events AS e USING (room_id, event_id) WHERE ep.user_id = ? AND ep.stream_ordering > ? AND ep.stream_ordering <= ? AND ep.notif = 1 ORDER BY ep.stream_ordering DESC LIMIT ? """ txn.execute(sql, (user_id, min_stream_ordering, max_stream_ordering, limit)) return cast(List[Tuple[str, str, int, str, bool, int]], txn.fetchall()) push_actions = await self.db_pool.runInteraction( "get_unread_push_actions_for_user_in_range_email", get_push_actions_txn ) # Make a list of dicts from the two sets of results. notifs = [ EmailPushAction( event_id=event_id, room_id=room_id, stream_ordering=stream_ordering, actions=_deserialize_action(actions, highlight), received_ts=received_ts, ) for event_id, room_id, stream_ordering, actions, highlight, received_ts in push_actions # Only include push actions with a stream ordering after any receipt, or without any # receipt present (invited to but never read rooms). if stream_ordering > receipts_by_room.get(room_id, 0) ] # Now sort it so it's ordered correctly, since currently it will # contain results from the first query, correctly ordered, followed # by results from the second query, but we want them all ordered # by received_ts (most recent first) notifs.sort(key=lambda r: -(r.received_ts or 0)) # Now return the first `limit` return notifs[:limit] async def get_if_maybe_push_in_range_for_user( self, user_id: str, min_stream_ordering: int ) -> bool: """A fast check to see if there might be something to push for the user since the given stream ordering. May return false positives. Useful to know whether to bother starting a pusher on start up or not. Args: user_id min_stream_ordering Returns: True if there may be push to process, False if there definitely isn't. """ def _get_if_maybe_push_in_range_for_user_txn(txn: LoggingTransaction) -> bool: sql = """ SELECT 1 FROM event_push_actions WHERE user_id = ? AND stream_ordering > ? AND notif = 1 LIMIT 1 """ txn.execute(sql, (user_id, min_stream_ordering)) return bool(txn.fetchone()) return await self.db_pool.runInteraction( "get_if_maybe_push_in_range_for_user", _get_if_maybe_push_in_range_for_user_txn, ) async def add_push_actions_to_staging( self, event_id: str, user_id_actions: Dict[str, Collection[Union[Mapping, str]]], count_as_unread: bool, thread_id: str, ) -> None: """Add the push actions for the event to the push action staging area. Args: event_id user_id_actions: A mapping of user_id to list of push actions, where an action can either be a string or dict. count_as_unread: Whether this event should increment unread counts. thread_id: The thread this event is parent of, if applicable. """ if not user_id_actions: return # This is a helper function for generating the necessary tuple that # can be used to insert into the `event_push_actions_staging` table. def _gen_entry( user_id: str, actions: Collection[Union[Mapping, str]] ) -> Tuple[str, str, str, int, int, int, str]: is_highlight = 1 if _action_has_highlight(actions) else 0 notif = 1 if "notify" in actions else 0 return ( event_id, # event_id column user_id, # user_id column _serialize_action(actions, bool(is_highlight)), # actions column notif, # notif column is_highlight, # highlight column int(count_as_unread), # unread column thread_id, # thread_id column ) await self.db_pool.simple_insert_many( "event_push_actions_staging", keys=( "event_id", "user_id", "actions", "notif", "highlight", "unread", "thread_id", ), values=[ _gen_entry(user_id, actions) for user_id, actions in user_id_actions.items() ], desc="add_push_actions_to_staging", ) async def remove_push_actions_from_staging(self, event_id: str) -> None: """Called if we failed to persist the event to ensure that stale push actions don't build up in the DB """ try: await self.db_pool.simple_delete( table="event_push_actions_staging", keyvalues={"event_id": event_id}, desc="remove_push_actions_from_staging", ) except Exception: # this method is called from an exception handler, so propagating # another exception here really isn't helpful - there's nothing # the caller can do about it. Just log the exception and move on. logger.exception( "Error removing push actions after event persistence failure" ) @wrap_as_background_process("event_push_action_stream_orderings") async def _find_stream_orderings_for_times(self) -> None: await self.db_pool.runInteraction( "_find_stream_orderings_for_times", self._find_stream_orderings_for_times_txn, ) def _find_stream_orderings_for_times_txn(self, txn: LoggingTransaction) -> None: logger.info("Searching for stream ordering 1 month ago") self.stream_ordering_month_ago = self._find_first_stream_ordering_after_ts_txn( txn, self._clock.time_msec() - 30 * 24 * 60 * 60 * 1000 ) logger.info( "Found stream ordering 1 month ago: it's %d", self.stream_ordering_month_ago ) logger.info("Searching for stream ordering 1 day ago") self.stream_ordering_day_ago = self._find_first_stream_ordering_after_ts_txn( txn, self._clock.time_msec() - 24 * 60 * 60 * 1000 ) logger.info( "Found stream ordering 1 day ago: it's %d", self.stream_ordering_day_ago ) async def find_first_stream_ordering_after_ts(self, ts: int) -> int: """Gets the stream ordering corresponding to a given timestamp. Specifically, finds the stream_ordering of the first event that was received on or after the timestamp. This is done by a binary search on the events table, since there is no index on received_ts, so is relatively slow. Args: ts: timestamp in millis Returns: stream ordering of the first event received on/after the timestamp """ return await self.db_pool.runInteraction( "_find_first_stream_ordering_after_ts_txn", self._find_first_stream_ordering_after_ts_txn, ts, ) @staticmethod def _find_first_stream_ordering_after_ts_txn( txn: LoggingTransaction, ts: int ) -> int: """ Find the stream_ordering of the first event that was received on or after a given timestamp. This is relatively slow as there is no index on received_ts but we can then use this to delete push actions before this. received_ts must necessarily be in the same order as stream_ordering and stream_ordering is indexed, so we manually binary search using stream_ordering Args: txn: ts: timestamp to search for Returns: The stream ordering """ txn.execute("SELECT MAX(stream_ordering) FROM events") max_stream_ordering = cast(Tuple[Optional[int]], txn.fetchone())[0] if max_stream_ordering is None: return 0 # We want the first stream_ordering in which received_ts is greater # than or equal to ts. Call this point X. # # We maintain the invariants: # # range_start <= X <= range_end # range_start = 0 range_end = max_stream_ordering + 1 # Given a stream_ordering, look up the timestamp at that # stream_ordering. # # The array may be sparse (we may be missing some stream_orderings). # We treat the gaps as the same as having the same value as the # preceding entry, because we will pick the lowest stream_ordering # which satisfies our requirement of received_ts >= ts. # # For example, if our array of events indexed by stream_ordering is # [10, , 20], we should treat this as being equivalent to # [10, 10, 20]. # sql = """ SELECT received_ts FROM events WHERE stream_ordering <= ? ORDER BY stream_ordering DESC LIMIT 1 """ while range_end - range_start > 0: middle = (range_end + range_start) // 2 txn.execute(sql, (middle,)) row = txn.fetchone() if row is None: # no rows with stream_ordering<=middle range_start = middle + 1 continue middle_ts = row[0] if ts > middle_ts: # we got a timestamp lower than the one we were looking for. # definitely need to look higher: X > middle. range_start = middle + 1 else: # we got a timestamp higher than (or the same as) the one we # were looking for. We aren't yet sure about the point we # looked up, but we can be sure that X <= middle. range_end = middle return range_end async def get_time_of_last_push_action_before( self, stream_ordering: int ) -> Optional[int]: def f(txn: LoggingTransaction) -> Optional[Tuple[int]]: sql = """ SELECT e.received_ts FROM event_push_actions AS ep JOIN events e ON ep.room_id = e.room_id AND ep.event_id = e.event_id WHERE ep.stream_ordering > ? AND notif = 1 ORDER BY ep.stream_ordering ASC LIMIT 1 """ txn.execute(sql, (stream_ordering,)) return cast(Optional[Tuple[int]], txn.fetchone()) result = await self.db_pool.runInteraction( "get_time_of_last_push_action_before", f ) return result[0] if result else None @wrap_as_background_process("rotate_notifs") async def _rotate_notifs(self) -> None: if self._doing_notif_rotation or self.stream_ordering_day_ago is None: return self._doing_notif_rotation = True try: # First we recalculate push summaries and delete stale push actions # for rooms/users with new receipts. while True: logger.debug("Handling new receipts") caught_up = await self.db_pool.runInteraction( "_handle_new_receipts_for_notifs_txn", self._handle_new_receipts_for_notifs_txn, ) if caught_up: break # Then we update the event push summaries for any new events while True: logger.info("Rotating notifications") caught_up = await self.db_pool.runInteraction( "_rotate_notifs", self._rotate_notifs_txn ) if caught_up: break # Finally we clear out old event push actions. await self._remove_old_push_actions_that_have_rotated() finally: self._doing_notif_rotation = False def _handle_new_receipts_for_notifs_txn(self, txn: LoggingTransaction) -> bool: """Check for new read receipts and delete from event push actions. Any push actions which predate the user's most recent read receipt are now redundant, so we can remove them from `event_push_actions` and update `event_push_summary`. Returns true if all new receipts have been processed. """ limit = 100 # The (inclusive) receipt stream ID that was previously processed.. min_receipts_stream_id = self.db_pool.simple_select_one_onecol_txn( txn, table="event_push_summary_last_receipt_stream_id", keyvalues={}, retcol="stream_id", ) max_receipts_stream_id = self._receipts_id_gen.get_current_token() # The (inclusive) event stream ordering that was previously summarised. old_rotate_stream_ordering = self.db_pool.simple_select_one_onecol_txn( txn, table="event_push_summary_stream_ordering", keyvalues={}, retcol="stream_ordering", ) sql = """ SELECT r.stream_id, r.room_id, r.user_id, e.stream_ordering FROM receipts_linearized AS r INNER JOIN events AS e USING (event_id) WHERE ? < r.stream_id AND r.stream_id <= ? AND user_id LIKE ? ORDER BY r.stream_id ASC LIMIT ? """ # We only want local users, so we add a dodgy filter to the above query # and recheck it below. user_filter = "%:" + self.hs.hostname txn.execute( sql, ( min_receipts_stream_id, max_receipts_stream_id, user_filter, limit, ), ) rows = txn.fetchall() # For each new read receipt we delete push actions from before it and # recalculate the summary. for _, room_id, user_id, stream_ordering in rows: # Only handle our own read receipts. if not self.hs.is_mine_id(user_id): continue txn.execute( """ DELETE FROM event_push_actions WHERE room_id = ? AND user_id = ? AND stream_ordering <= ? AND highlight = 0 """, (room_id, user_id, stream_ordering), ) # Fetch the notification counts between the stream ordering of the # latest receipt and what was previously summarised. notif_count, unread_count = self._get_notif_unread_count_for_user_room( txn, room_id, user_id, stream_ordering, old_rotate_stream_ordering ) # Replace the previous summary with the new counts. # # TODO(threads): Upsert per-thread instead of setting them all to main. self.db_pool.simple_upsert_txn( txn, table="event_push_summary", keyvalues={"room_id": room_id, "user_id": user_id}, values={ "notif_count": notif_count, "unread_count": unread_count, "stream_ordering": old_rotate_stream_ordering, "last_receipt_stream_ordering": stream_ordering, "thread_id": "main", }, ) # We always update `event_push_summary_last_receipt_stream_id` to # ensure that we don't rescan the same receipts for remote users. upper_limit = max_receipts_stream_id if len(rows) >= limit: # If we pulled out a limited number of rows we only update the # position to the last receipt we processed, so we continue # processing the rest next iteration. upper_limit = rows[-1][0] self.db_pool.simple_update_txn( txn, table="event_push_summary_last_receipt_stream_id", keyvalues={}, updatevalues={"stream_id": upper_limit}, ) return len(rows) < limit def _rotate_notifs_txn(self, txn: LoggingTransaction) -> bool: """Archives older notifications (from event_push_actions) into event_push_summary. Returns whether the archiving process has caught up or not. """ # The (inclusive) event stream ordering that was previously summarised. old_rotate_stream_ordering = self.db_pool.simple_select_one_onecol_txn( txn, table="event_push_summary_stream_ordering", keyvalues={}, retcol="stream_ordering", ) # We don't to try and rotate millions of rows at once, so we cap the # maximum stream ordering we'll rotate before. txn.execute( """ SELECT stream_ordering FROM event_push_actions WHERE stream_ordering > ? ORDER BY stream_ordering ASC LIMIT 1 OFFSET ? """, (old_rotate_stream_ordering, self._rotate_count), ) stream_row = txn.fetchone() if stream_row: (offset_stream_ordering,) = stream_row # We need to bound by the current token to ensure that we handle # out-of-order writes correctly. rotate_to_stream_ordering = min( offset_stream_ordering, self._stream_id_gen.get_current_token() ) caught_up = False else: rotate_to_stream_ordering = self._stream_id_gen.get_current_token() caught_up = True logger.info("Rotating notifications up to: %s", rotate_to_stream_ordering) self._rotate_notifs_before_txn( txn, old_rotate_stream_ordering, rotate_to_stream_ordering ) return caught_up def _rotate_notifs_before_txn( self, txn: LoggingTransaction, old_rotate_stream_ordering: int, rotate_to_stream_ordering: int, ) -> None: """Archives older notifications (from event_push_actions) into event_push_summary. Any event_push_actions between old_rotate_stream_ordering (exclusive) and rotate_to_stream_ordering (inclusive) will be added to the event_push_summary table. Args: txn: The database transaction. old_rotate_stream_ordering: The previous maximum event stream ordering. rotate_to_stream_ordering: The new maximum event stream ordering to summarise. """ # Calculate the new counts that should be upserted into event_push_summary sql = """ SELECT user_id, room_id, coalesce(old.%s, 0) + upd.cnt, upd.stream_ordering FROM ( SELECT user_id, room_id, count(*) as cnt, max(ea.stream_ordering) as stream_ordering FROM event_push_actions AS ea LEFT JOIN event_push_summary AS old USING (user_id, room_id) WHERE ? < ea.stream_ordering AND ea.stream_ordering <= ? AND ( old.last_receipt_stream_ordering IS NULL OR old.last_receipt_stream_ordering < ea.stream_ordering ) AND %s = 1 GROUP BY user_id, room_id ) AS upd LEFT JOIN event_push_summary AS old USING (user_id, room_id) """ # First get the count of unread messages. txn.execute( sql % ("unread_count", "unread"), (old_rotate_stream_ordering, rotate_to_stream_ordering), ) # We need to merge results from the two requests (the one that retrieves the # unread count and the one that retrieves the notifications count) into a single # object because we might not have the same amount of rows in each of them. To do # this, we use a dict indexed on the user ID and room ID to make it easier to # populate. summaries: Dict[Tuple[str, str], _EventPushSummary] = {} for row in txn: summaries[(row[0], row[1])] = _EventPushSummary( unread_count=row[2], stream_ordering=row[3], notif_count=0, ) # Then get the count of notifications. txn.execute( sql % ("notif_count", "notif"), (old_rotate_stream_ordering, rotate_to_stream_ordering), ) for row in txn: if (row[0], row[1]) in summaries: summaries[(row[0], row[1])].notif_count = row[2] else: # Because the rules on notifying are different than the rules on marking # a message unread, we might end up with messages that notify but aren't # marked unread, so we might not have a summary for this (user, room) # tuple to complete. summaries[(row[0], row[1])] = _EventPushSummary( unread_count=0, stream_ordering=row[3], notif_count=row[2], ) logger.info("Rotating notifications, handling %d rows", len(summaries)) # TODO(threads): Update on a per-thread basis. self.db_pool.simple_upsert_many_txn( txn, table="event_push_summary", key_names=("user_id", "room_id"), key_values=[(user_id, room_id) for user_id, room_id in summaries], value_names=("notif_count", "unread_count", "stream_ordering", "thread_id"), value_values=[ ( summary.notif_count, summary.unread_count, summary.stream_ordering, "main", ) for summary in summaries.values() ], ) txn.execute( "UPDATE event_push_summary_stream_ordering SET stream_ordering = ?", (rotate_to_stream_ordering,), ) async def _remove_old_push_actions_that_have_rotated(self) -> None: """Clear out old push actions that have been summarised.""" # We want to clear out anything that is older than a day that *has* already # been rotated. rotated_upto_stream_ordering = await self.db_pool.simple_select_one_onecol( table="event_push_summary_stream_ordering", keyvalues={}, retcol="stream_ordering", ) max_stream_ordering_to_delete = min( rotated_upto_stream_ordering, self.stream_ordering_day_ago ) def remove_old_push_actions_that_have_rotated_txn( txn: LoggingTransaction, ) -> bool: # We don't want to clear out too much at a time, so we bound our # deletes. batch_size = self._rotate_count txn.execute( """ SELECT stream_ordering FROM event_push_actions WHERE stream_ordering <= ? AND highlight = 0 ORDER BY stream_ordering ASC LIMIT 1 OFFSET ? """, ( max_stream_ordering_to_delete, batch_size, ), ) stream_row = txn.fetchone() if stream_row: (stream_ordering,) = stream_row else: stream_ordering = max_stream_ordering_to_delete # We need to use a inclusive bound here to handle the case where a # single stream ordering has more than `batch_size` rows. txn.execute( """ DELETE FROM event_push_actions WHERE stream_ordering <= ? AND highlight = 0 """, (stream_ordering,), ) logger.info("Rotating notifications, deleted %s push actions", txn.rowcount) return txn.rowcount < batch_size while True: done = await self.db_pool.runInteraction( "_remove_old_push_actions_that_have_rotated", remove_old_push_actions_that_have_rotated_txn, ) if done: break class EventPushActionsStore(EventPushActionsWorkerStore): EPA_HIGHLIGHT_INDEX = "epa_highlight_index" def __init__( self, database: DatabasePool, db_conn: LoggingDatabaseConnection, hs: "HomeServer", ): super().__init__(database, db_conn, hs) self.db_pool.updates.register_background_index_update( self.EPA_HIGHLIGHT_INDEX, index_name="event_push_actions_u_highlight", table="event_push_actions", columns=["user_id", "stream_ordering"], ) self.db_pool.updates.register_background_index_update( "event_push_actions_highlights_index", index_name="event_push_actions_highlights_index", table="event_push_actions", columns=["user_id", "room_id", "topological_ordering", "stream_ordering"], where_clause="highlight=1", ) # Add index to make deleting old push actions faster. self.db_pool.updates.register_background_index_update( "event_push_actions_stream_highlight_index", index_name="event_push_actions_stream_highlight_index", table="event_push_actions", columns=["highlight", "stream_ordering"], where_clause="highlight=0", ) async def get_push_actions_for_user( self, user_id: str, before: Optional[str] = None, limit: int = 50, only_highlight: bool = False, ) -> List[UserPushAction]: def f( txn: LoggingTransaction, ) -> List[Tuple[str, str, int, int, str, bool, str, int]]: before_clause = "" if before: before_clause = "AND epa.stream_ordering < ?" args = [user_id, before, limit] else: args = [user_id, limit] if only_highlight: if len(before_clause) > 0: before_clause += " " before_clause += "AND epa.highlight = 1" # NB. This assumes event_ids are globally unique since # it makes the query easier to index sql = """ SELECT epa.event_id, epa.room_id, epa.stream_ordering, epa.topological_ordering, epa.actions, epa.highlight, epa.profile_tag, e.received_ts FROM event_push_actions epa, events e WHERE epa.event_id = e.event_id AND epa.user_id = ? %s AND epa.notif = 1 ORDER BY epa.stream_ordering DESC LIMIT ? """ % ( before_clause, ) txn.execute(sql, args) return cast( List[Tuple[str, str, int, int, str, bool, str, int]], txn.fetchall() ) push_actions = await self.db_pool.runInteraction("get_push_actions_for_user", f) return [ UserPushAction( event_id=row[0], room_id=row[1], stream_ordering=row[2], actions=_deserialize_action(row[4], row[5]), received_ts=row[7], topological_ordering=row[3], highlight=row[5], profile_tag=row[6], ) for row in push_actions ] def _action_has_highlight(actions: Collection[Union[Mapping, str]]) -> bool: for action in actions: if not isinstance(action, dict): continue if action.get("set_tweak", None) == "highlight": return action.get("value", True) return False @attr.s(slots=True, auto_attribs=True) class _EventPushSummary: """Summary of pending event push actions for a given user in a given room. Used in _rotate_notifs_before_txn to manipulate results from event_push_actions. """ unread_count: int stream_ordering: int notif_count: int