diff options
Diffstat (limited to 'synapse/storage')
| -rw-r--r-- | synapse/storage/database.py | 22 | ||||
| -rw-r--r-- | synapse/storage/databases/main/event_federation.py | 185 | ||||
| -rw-r--r-- | synapse/storage/databases/main/events.py | 535 | ||||
| -rw-r--r-- | synapse/storage/databases/main/room.py | 51 | ||||
| -rw-r--r-- | synapse/storage/databases/main/schema/delta/59/04_event_auth_chains.sql | 52 | ||||
| -rw-r--r-- | synapse/storage/databases/main/schema/delta/59/04_event_auth_chains.sql.postgres | 16 |
6 files changed, 839 insertions, 22 deletions
diff --git a/synapse/storage/database.py b/synapse/storage/database.py index b70ca3087b..6cfadc2b4e 100644 --- a/synapse/storage/database.py +++ b/synapse/storage/database.py @@ -179,6 +179,9 @@ class LoggingDatabaseConnection: _CallbackListEntry = Tuple["Callable[..., None]", Iterable[Any], Dict[str, Any]] +R = TypeVar("R") + + class LoggingTransaction: """An object that almost-transparently proxies for the 'txn' object passed to the constructor. Adds logging and metrics to the .execute() @@ -266,6 +269,20 @@ class LoggingTransaction: for val in args: self.execute(sql, val) + def execute_values(self, sql: str, *args: Any) -> List[Tuple]: + """Corresponds to psycopg2.extras.execute_values. Only available when + using postgres. + + Always sets fetch=True when caling `execute_values`, so will return the + results. + """ + assert isinstance(self.database_engine, PostgresEngine) + from psycopg2.extras import execute_values # type: ignore + + return self._do_execute( + lambda *x: execute_values(self.txn, *x, fetch=True), sql, *args + ) + def execute(self, sql: str, *args: Any) -> None: self._do_execute(self.txn.execute, sql, *args) @@ -276,7 +293,7 @@ class LoggingTransaction: "Strip newlines out of SQL so that the loggers in the DB are on one line" return " ".join(line.strip() for line in sql.splitlines() if line.strip()) - def _do_execute(self, func, sql: str, *args: Any) -> None: + def _do_execute(self, func: Callable[..., R], sql: str, *args: Any) -> R: sql = self._make_sql_one_line(sql) # TODO(paul): Maybe use 'info' and 'debug' for values? @@ -347,9 +364,6 @@ class PerformanceCounters: return top_n_counters -R = TypeVar("R") - - class DatabasePool: """Wraps a single physical database and connection pool. diff --git a/synapse/storage/databases/main/event_federation.py b/synapse/storage/databases/main/event_federation.py index ebffd89251..8326640d20 100644 --- a/synapse/storage/databases/main/event_federation.py +++ b/synapse/storage/databases/main/event_federation.py @@ -24,6 +24,8 @@ from synapse.storage._base import SQLBaseStore, make_in_list_sql_clause from synapse.storage.database import DatabasePool, LoggingTransaction from synapse.storage.databases.main.events_worker import EventsWorkerStore from synapse.storage.databases.main.signatures import SignatureWorkerStore +from synapse.storage.engines import PostgresEngine +from synapse.storage.types import Cursor from synapse.types import Collection from synapse.util.caches.descriptors import cached from synapse.util.caches.lrucache import LruCache @@ -32,6 +34,11 @@ from synapse.util.iterutils import batch_iter logger = logging.getLogger(__name__) +class _NoChainCoverIndex(Exception): + def __init__(self, room_id: str): + super().__init__("Unexpectedly no chain cover for events in %s" % (room_id,)) + + class EventFederationWorkerStore(EventsWorkerStore, SignatureWorkerStore, SQLBaseStore): def __init__(self, database: DatabasePool, db_conn, hs): super().__init__(database, db_conn, hs) @@ -151,15 +158,193 @@ class EventFederationWorkerStore(EventsWorkerStore, SignatureWorkerStore, SQLBas The set of the difference in auth chains. """ + # Check if we have indexed the room so we can use the chain cover + # algorithm. + room = await self.get_room(room_id) + if room["has_auth_chain_index"]: + try: + return await self.db_pool.runInteraction( + "get_auth_chain_difference_chains", + self._get_auth_chain_difference_using_cover_index_txn, + room_id, + state_sets, + ) + except _NoChainCoverIndex: + # For whatever reason we don't actually have a chain cover index + # for the events in question, so we fall back to the old method. + pass + return await self.db_pool.runInteraction( "get_auth_chain_difference", self._get_auth_chain_difference_txn, state_sets, ) + def _get_auth_chain_difference_using_cover_index_txn( + self, txn: Cursor, room_id: str, state_sets: List[Set[str]] + ) -> Set[str]: + """Calculates the auth chain difference using the chain index. + + See docs/auth_chain_difference_algorithm.md for details + """ + + # First we look up the chain ID/sequence numbers for all the events, and + # work out the chain/sequence numbers reachable from each state set. + + initial_events = set(state_sets[0]).union(*state_sets[1:]) + + # Map from event_id -> (chain ID, seq no) + chain_info = {} # type: Dict[str, Tuple[int, int]] + + # Map from chain ID -> seq no -> event Id + chain_to_event = {} # type: Dict[int, Dict[int, str]] + + # All the chains that we've found that are reachable from the state + # sets. + seen_chains = set() # type: Set[int] + + sql = """ + SELECT event_id, chain_id, sequence_number + FROM event_auth_chains + WHERE %s + """ + for batch in batch_iter(initial_events, 1000): + clause, args = make_in_list_sql_clause( + txn.database_engine, "event_id", batch + ) + txn.execute(sql % (clause,), args) + + for event_id, chain_id, sequence_number in txn: + chain_info[event_id] = (chain_id, sequence_number) + seen_chains.add(chain_id) + chain_to_event.setdefault(chain_id, {})[sequence_number] = event_id + + # Check that we actually have a chain ID for all the events. + events_missing_chain_info = initial_events.difference(chain_info) + if events_missing_chain_info: + # This can happen due to e.g. downgrade/upgrade of the server. We + # raise an exception and fall back to the previous algorithm. + logger.info( + "Unexpectedly found that events don't have chain IDs in room %s: %s", + room_id, + events_missing_chain_info, + ) + raise _NoChainCoverIndex(room_id) + + # Corresponds to `state_sets`, except as a map from chain ID to max + # sequence number reachable from the state set. + set_to_chain = [] # type: List[Dict[int, int]] + for state_set in state_sets: + chains = {} # type: Dict[int, int] + set_to_chain.append(chains) + + for event_id in state_set: + chain_id, seq_no = chain_info[event_id] + + chains[chain_id] = max(seq_no, chains.get(chain_id, 0)) + + # Now we look up all links for the chains we have, adding chains to + # set_to_chain that are reachable from each set. + sql = """ + SELECT + origin_chain_id, origin_sequence_number, + target_chain_id, target_sequence_number + FROM event_auth_chain_links + WHERE %s + """ + + # (We need to take a copy of `seen_chains` as we want to mutate it in + # the loop) + for batch in batch_iter(set(seen_chains), 1000): + clause, args = make_in_list_sql_clause( + txn.database_engine, "origin_chain_id", batch + ) + txn.execute(sql % (clause,), args) + + for ( + origin_chain_id, + origin_sequence_number, + target_chain_id, + target_sequence_number, + ) in txn: + for chains in set_to_chain: + # chains are only reachable if the origin sequence number of + # the link is less than the max sequence number in the + # origin chain. + if origin_sequence_number <= chains.get(origin_chain_id, 0): + chains[target_chain_id] = max( + target_sequence_number, chains.get(target_chain_id, 0), + ) + + seen_chains.add(target_chain_id) + + # Now for each chain we figure out the maximum sequence number reachable + # from *any* state set and the minimum sequence number reachable from + # *all* state sets. Events in that range are in the auth chain + # difference. + result = set() + + # Mapping from chain ID to the range of sequence numbers that should be + # pulled from the database. + chain_to_gap = {} # type: Dict[int, Tuple[int, int]] + + for chain_id in seen_chains: + min_seq_no = min(chains.get(chain_id, 0) for chains in set_to_chain) + max_seq_no = max(chains.get(chain_id, 0) for chains in set_to_chain) + + if min_seq_no < max_seq_no: + # We have a non empty gap, try and fill it from the events that + # we have, otherwise add them to the list of gaps to pull out + # from the DB. + for seq_no in range(min_seq_no + 1, max_seq_no + 1): + event_id = chain_to_event.get(chain_id, {}).get(seq_no) + if event_id: + result.add(event_id) + else: + chain_to_gap[chain_id] = (min_seq_no, max_seq_no) + break + + if not chain_to_gap: + # If there are no gaps to fetch, we're done! + return result + + if isinstance(self.database_engine, PostgresEngine): + # We can use `execute_values` to efficiently fetch the gaps when + # using postgres. + sql = """ + SELECT event_id + FROM event_auth_chains AS c, (VALUES ?) AS l(chain_id, min_seq, max_seq) + WHERE + c.chain_id = l.chain_id + AND min_seq < sequence_number AND sequence_number <= max_seq + """ + + args = [ + (chain_id, min_no, max_no) + for chain_id, (min_no, max_no) in chain_to_gap.items() + ] + + rows = txn.execute_values(sql, args) + result.update(r for r, in rows) + else: + # For SQLite we just fall back to doing a noddy for loop. + sql = """ + SELECT event_id FROM event_auth_chains + WHERE chain_id = ? AND ? < sequence_number AND sequence_number <= ? + """ + for chain_id, (min_no, max_no) in chain_to_gap.items(): + txn.execute(sql, (chain_id, min_no, max_no)) + result.update(r for r, in txn) + + return result + def _get_auth_chain_difference_txn( self, txn, state_sets: List[Set[str]] ) -> Set[str]: + """Calculates the auth chain difference using a breadth first search. + + This is used when we don't have a cover index for the room. + """ # Algorithm Description # ~~~~~~~~~~~~~~~~~~~~~ diff --git a/synapse/storage/databases/main/events.py b/synapse/storage/databases/main/events.py index 5e7753e09b..186f064036 100644 --- a/synapse/storage/databases/main/events.py +++ b/synapse/storage/databases/main/events.py @@ -17,7 +17,17 @@ import itertools import logging from collections import OrderedDict, namedtuple -from typing import TYPE_CHECKING, Any, Dict, Iterable, List, Optional, Set, Tuple +from typing import ( + TYPE_CHECKING, + Any, + Dict, + Generator, + Iterable, + List, + Optional, + Set, + Tuple, +) import attr from prometheus_client import Counter @@ -33,9 +43,10 @@ from synapse.storage._base import db_to_json, make_in_list_sql_clause from synapse.storage.database import DatabasePool, LoggingTransaction from synapse.storage.databases.main.search import SearchEntry from synapse.storage.util.id_generators import MultiWriterIdGenerator +from synapse.storage.util.sequence import build_sequence_generator from synapse.types import StateMap, get_domain_from_id from synapse.util import json_encoder -from synapse.util.iterutils import batch_iter +from synapse.util.iterutils import batch_iter, sorted_topologically if TYPE_CHECKING: from synapse.server import HomeServer @@ -89,6 +100,14 @@ class PersistEventsStore: self._clock = hs.get_clock() self._instance_name = hs.get_instance_name() + def get_chain_id_txn(txn): + txn.execute("SELECT COALESCE(max(chain_id), 0) FROM event_auth_chains") + return txn.fetchone()[0] + + self._event_chain_id_gen = build_sequence_generator( + db.engine, get_chain_id_txn, "event_auth_chain_id" + ) + self._ephemeral_messages_enabled = hs.config.enable_ephemeral_messages self.is_mine_id = hs.is_mine_id @@ -366,6 +385,36 @@ class PersistEventsStore: # Insert into event_to_state_groups. self._store_event_state_mappings_txn(txn, events_and_contexts) + self._persist_event_auth_chain_txn(txn, [e for e, _ in events_and_contexts]) + + # _store_rejected_events_txn filters out any events which were + # rejected, and returns the filtered list. + events_and_contexts = self._store_rejected_events_txn( + txn, events_and_contexts=events_and_contexts + ) + + # From this point onwards the events are only ones that weren't + # rejected. + + self._update_metadata_tables_txn( + txn, + events_and_contexts=events_and_contexts, + all_events_and_contexts=all_events_and_contexts, + backfilled=backfilled, + ) + + # We call this last as it assumes we've inserted the events into + # room_memberships, where applicable. + self._update_current_state_txn(txn, state_delta_for_room, min_stream_order) + + def _persist_event_auth_chain_txn( + self, txn: LoggingTransaction, events: List[EventBase], + ) -> None: + + # We only care about state events, so this if there are no state events. + if not any(e.is_state() for e in events): + return + # We want to store event_auth mappings for rejected events, as they're # used in state res v2. # This is only necessary if the rejected event appears in an accepted @@ -381,31 +430,357 @@ class PersistEventsStore: "room_id": event.room_id, "auth_id": auth_id, } - for event, _ in events_and_contexts + for event in events for auth_id in event.auth_event_ids() if event.is_state() ], ) - # _store_rejected_events_txn filters out any events which were - # rejected, and returns the filtered list. - events_and_contexts = self._store_rejected_events_txn( - txn, events_and_contexts=events_and_contexts + # We now calculate chain ID/sequence numbers for any state events we're + # persisting. We ignore out of band memberships as we're not in the room + # and won't have their auth chain (we'll fix it up later if we join the + # room). + # + # See: docs/auth_chain_difference_algorithm.md + + # We ignore legacy rooms that we aren't filling the chain cover index + # for. + rows = self.db_pool.simple_select_many_txn( + txn, + table="rooms", + column="room_id", + iterable={event.room_id for event in events if event.is_state()}, + keyvalues={}, + retcols=("room_id", "has_auth_chain_index"), ) + rooms_using_chain_index = { + row["room_id"] for row in rows if row["has_auth_chain_index"] + } - # From this point onwards the events are only ones that weren't - # rejected. + state_events = { + event.event_id: event + for event in events + if event.is_state() and event.room_id in rooms_using_chain_index + } - self._update_metadata_tables_txn( + if not state_events: + return + + # Map from event ID to chain ID/sequence number. + chain_map = {} # type: Dict[str, Tuple[int, int]] + + # We need to know the type/state_key and auth events of the events we're + # calculating chain IDs for. We don't rely on having the full Event + # instances as we'll potentially be pulling more events from the DB and + # we don't need the overhead of fetching/parsing the full event JSON. + event_to_types = { + e.event_id: (e.type, e.state_key) for e in state_events.values() + } + event_to_auth_chain = { + e.event_id: e.auth_event_ids() for e in state_events.values() + } + + # Set of event IDs to calculate chain ID/seq numbers for. + events_to_calc_chain_id_for = set(state_events) + + # We check if there are any events that need to be handled in the rooms + # we're looking at. These should just be out of band memberships, where + # we didn't have the auth chain when we first persisted. + rows = self.db_pool.simple_select_many_txn( txn, - events_and_contexts=events_and_contexts, - all_events_and_contexts=all_events_and_contexts, - backfilled=backfilled, + table="event_auth_chain_to_calculate", + keyvalues={}, + column="room_id", + iterable={e.room_id for e in state_events.values()}, + retcols=("event_id", "type", "state_key"), ) + for row in rows: + event_id = row["event_id"] + event_type = row["type"] + state_key = row["state_key"] + + # (We could pull out the auth events for all rows at once using + # simple_select_many, but this case happens rarely and almost always + # with a single row.) + auth_events = self.db_pool.simple_select_onecol_txn( + txn, "event_auth", keyvalues={"event_id": event_id}, retcol="auth_id", + ) - # We call this last as it assumes we've inserted the events into - # room_memberships, where applicable. - self._update_current_state_txn(txn, state_delta_for_room, min_stream_order) + events_to_calc_chain_id_for.add(event_id) + event_to_types[event_id] = (event_type, state_key) + event_to_auth_chain[event_id] = auth_events + + # First we get the chain ID and sequence numbers for the events' + # auth events (that aren't also currently being persisted). + # + # Note that there there is an edge case here where we might not have + # calculated chains and sequence numbers for events that were "out + # of band". We handle this case by fetching the necessary info and + # adding it to the set of events to calculate chain IDs for. + + missing_auth_chains = { + a_id + for auth_events in event_to_auth_chain.values() + for a_id in auth_events + if a_id not in events_to_calc_chain_id_for + } + + # We loop here in case we find an out of band membership and need to + # fetch their auth event info. + while missing_auth_chains: + sql = """ + SELECT event_id, events.type, state_key, chain_id, sequence_number + FROM events + INNER JOIN state_events USING (event_id) + LEFT JOIN event_auth_chains USING (event_id) + WHERE + """ + clause, args = make_in_list_sql_clause( + txn.database_engine, "event_id", missing_auth_chains, + ) + txn.execute(sql + clause, args) + + missing_auth_chains.clear() + + for auth_id, event_type, state_key, chain_id, sequence_number in txn: + event_to_types[auth_id] = (event_type, state_key) + + if chain_id is None: + # No chain ID, so the event was persisted out of band. + # We add to list of events to calculate auth chains for. + + events_to_calc_chain_id_for.add(auth_id) + + event_to_auth_chain[ + auth_id + ] = self.db_pool.simple_select_onecol_txn( + txn, + "event_auth", + keyvalues={"event_id": auth_id}, + retcol="auth_id", + ) + + missing_auth_chains.update( + e + for e in event_to_auth_chain[auth_id] + if e not in event_to_types + ) + else: + chain_map[auth_id] = (chain_id, sequence_number) + + # Now we check if we have any events where we don't have auth chain, + # this should only be out of band memberships. + for event_id in sorted_topologically(event_to_auth_chain, event_to_auth_chain): + for auth_id in event_to_auth_chain[event_id]: + if ( + auth_id not in chain_map + and auth_id not in events_to_calc_chain_id_for + ): + events_to_calc_chain_id_for.discard(event_id) + + # If this is an event we're trying to persist we add it to + # the list of events to calculate chain IDs for next time + # around. (Otherwise we will have already added it to the + # table). + event = state_events.get(event_id) + if event: + self.db_pool.simple_insert_txn( + txn, + table="event_auth_chain_to_calculate", + values={ + "event_id": event.event_id, + "room_id": event.room_id, + "type": event.type, + "state_key": event.state_key, + }, + ) + + # We stop checking the event's auth events since we've + # discarded it. + break + + if not events_to_calc_chain_id_for: + return + + # We now calculate the chain IDs/sequence numbers for the events. We + # do this by looking at the chain ID and sequence number of any auth + # event with the same type/state_key and incrementing the sequence + # number by one. If there was no match or the chain ID/sequence + # number is already taken we generate a new chain. + # + # We need to do this in a topologically sorted order as we want to + # generate chain IDs/sequence numbers of an event's auth events + # before the event itself. + chains_tuples_allocated = set() # type: Set[Tuple[int, int]] + new_chain_tuples = {} # type: Dict[str, Tuple[int, int]] + for event_id in sorted_topologically( + events_to_calc_chain_id_for, event_to_auth_chain + ): + existing_chain_id = None + for auth_id in event_to_auth_chain[event_id]: + if event_to_types.get(event_id) == event_to_types.get(auth_id): + existing_chain_id = chain_map[auth_id] + break + + new_chain_tuple = None + if existing_chain_id: + # We found a chain ID/sequence number candidate, check its + # not already taken. + proposed_new_id = existing_chain_id[0] + proposed_new_seq = existing_chain_id[1] + 1 + if (proposed_new_id, proposed_new_seq) not in chains_tuples_allocated: + already_allocated = self.db_pool.simple_select_one_onecol_txn( + txn, + table="event_auth_chains", + keyvalues={ + "chain_id": proposed_new_id, + "sequence_number": proposed_new_seq, + }, + retcol="event_id", + allow_none=True, + ) + if already_allocated: + # Mark it as already allocated so we don't need to hit + # the DB again. + chains_tuples_allocated.add((proposed_new_id, proposed_new_seq)) + else: + new_chain_tuple = ( + proposed_new_id, + proposed_new_seq, + ) + + if not new_chain_tuple: + new_chain_tuple = (self._event_chain_id_gen.get_next_id_txn(txn), 1) + + chains_tuples_allocated.add(new_chain_tuple) + + chain_map[event_id] = new_chain_tuple + new_chain_tuples[event_id] = new_chain_tuple + + self.db_pool.simple_insert_many_txn( + txn, + table="event_auth_chains", + values=[ + {"event_id": event_id, "chain_id": c_id, "sequence_number": seq} + for event_id, (c_id, seq) in new_chain_tuples.items() + ], + ) + + self.db_pool.simple_delete_many_txn( + txn, + table="event_auth_chain_to_calculate", + keyvalues={}, + column="event_id", + iterable=new_chain_tuples, + ) + + # Now we need to calculate any new links between chains caused by + # the new events. + # + # Links are pairs of chain ID/sequence numbers such that for any + # event A (CA, SA) and any event B (CB, SB), B is in A's auth chain + # if and only if there is at least one link (CA, S1) -> (CB, S2) + # where SA >= S1 and S2 >= SB. + # + # We try and avoid adding redundant links to the table, e.g. if we + # have two links between two chains which both start/end at the + # sequence number event (or cross) then one can be safely dropped. + # + # To calculate new links we look at every new event and: + # 1. Fetch the chain ID/sequence numbers of its auth events, + # discarding any that are reachable by other auth events, or + # that have the same chain ID as the event. + # 2. For each retained auth event we: + # a. Add a link from the event's to the auth event's chain + # ID/sequence number; and + # b. Add a link from the event to every chain reachable by the + # auth event. + + # Step 1, fetch all existing links from all the chains we've seen + # referenced. + chain_links = _LinkMap() + rows = self.db_pool.simple_select_many_txn( + txn, + table="event_auth_chain_links", + column="origin_chain_id", + iterable={chain_id for chain_id, _ in chain_map.values()}, + keyvalues={}, + retcols=( + "origin_chain_id", + "origin_sequence_number", + "target_chain_id", + "target_sequence_number", + ), + ) + for row in rows: + chain_links.add_link( + (row["origin_chain_id"], row["origin_sequence_number"]), + (row["target_chain_id"], row["target_sequence_number"]), + new=False, + ) + + # We do this in toplogical order to avoid adding redundant links. + for event_id in sorted_topologically( + events_to_calc_chain_id_for, event_to_auth_chain + ): + chain_id, sequence_number = chain_map[event_id] + + # Filter out auth events that are reachable by other auth + # events. We do this by looking at every permutation of pairs of + # auth events (A, B) to check if B is reachable from A. + reduction = { + a_id + for a_id in event_to_auth_chain[event_id] + if chain_map[a_id][0] != chain_id + } + for start_auth_id, end_auth_id in itertools.permutations( + event_to_auth_chain[event_id], r=2, + ): + if chain_links.exists_path_from( + chain_map[start_auth_id], chain_map[end_auth_id] + ): + reduction.discard(end_auth_id) + + # Step 2, figure out what the new links are from the reduced + # list of auth events. + for auth_id in reduction: + auth_chain_id, auth_sequence_number = chain_map[auth_id] + + # Step 2a, add link between the event and auth event + chain_links.add_link( + (chain_id, sequence_number), (auth_chain_id, auth_sequence_number) + ) + + # Step 2b, add a link to chains reachable from the auth + # event. + for target_id, target_seq in chain_links.get_links_from( + (auth_chain_id, auth_sequence_number) + ): + if target_id == chain_id: + continue + + chain_links.add_link( + (chain_id, sequence_number), (target_id, target_seq) + ) + + self.db_pool.simple_insert_many_txn( + txn, + table="event_auth_chain_links", + values=[ + { + "origin_chain_id": source_id, + "origin_sequence_number": source_seq, + "target_chain_id": target_id, + "target_sequence_number": target_seq, + } + for ( + source_id, + source_seq, + target_id, + target_seq, + ) in chain_links.get_additions() + ], + ) def _persist_transaction_ids_txn( self, @@ -1521,3 +1896,131 @@ class PersistEventsStore: if not ev.internal_metadata.is_outlier() ], ) + + +@attr.s(slots=True) +class _LinkMap: + """A helper type for tracking links between chains. + """ + + # Stores the set of links as nested maps: source chain ID -> target chain ID + # -> source sequence number -> target sequence number. + maps = attr.ib(type=Dict[int, Dict[int, Dict[int, int]]], factory=dict) + + # Stores the links that have been added (with new set to true), as tuples of + # `(source chain ID, source sequence no, target chain ID, target sequence no.)` + additions = attr.ib(type=Set[Tuple[int, int, int, int]], factory=set) + + def add_link( + self, + src_tuple: Tuple[int, int], + target_tuple: Tuple[int, int], + new: bool = True, + ) -> bool: + """Add a new link between two chains, ensuring no redundant links are added. + + New links should be added in topological order. + + Args: + src_tuple: The chain ID/sequence number of the source of the link. + target_tuple: The chain ID/sequence number of the target of the link. + new: Whether this is a "new" link, i.e. should it be returned + by `get_additions`. + + Returns: + True if a link was added, false if the given link was dropped as redundant + """ + src_chain, src_seq = src_tuple + target_chain, target_seq = target_tuple + + current_links = self.maps.setdefault(src_chain, {}).setdefault(target_chain, {}) + + assert src_chain != target_chain + + if new: + # Check if the new link is redundant + for current_seq_src, current_seq_target in current_links.items(): + # If a link "crosses" another link then its redundant. For example + # in the following link 1 (L1) is redundant, as any event reachable + # via L1 is *also* reachable via L2. + # + # Chain A Chain B + # | | + # L1 |------ | + # | | | + # L2 |---- | -->| + # | | | + # | |--->| + # | | + # | | + # + # So we only need to keep links which *do not* cross, i.e. links + # that both start and end above or below an existing link. + # + # Note, since we add links in topological ordering we should never + # see `src_seq` less than `current_seq_src`. + + if current_seq_src <= src_seq and target_seq <= current_seq_target: + # This new link is redundant, nothing to do. + return False + + self.additions.add((src_chain, src_seq, target_chain, target_seq)) + + current_links[src_seq] = target_seq + return True + + def get_links_from( + self, src_tuple: Tuple[int, int] + ) -> Generator[Tuple[int, int], None, None]: + """Gets the chains reachable from the given chain/sequence number. + + Yields: + The chain ID and sequence number the link points to. + """ + src_chain, src_seq = src_tuple + for target_id, sequence_numbers in self.maps.get(src_chain, {}).items(): + for link_src_seq, target_seq in sequence_numbers.items(): + if link_src_seq <= src_seq: + yield target_id, target_seq + + def get_links_between( + self, source_chain: int, target_chain: int + ) -> Generator[Tuple[int, int], None, None]: + """Gets the links between two chains. + + Yields: + The source and target sequence numbers. + """ + + yield from self.maps.get(source_chain, {}).get(target_chain, {}).items() + + def get_additions(self) -> Generator[Tuple[int, int, int, int], None, None]: + """Gets any newly added links. + + Yields: + The source chain ID/sequence number and target chain ID/sequence number + """ + + for src_chain, src_seq, target_chain, _ in self.additions: + target_seq = self.maps.get(src_chain, {}).get(target_chain, {}).get(src_seq) + if target_seq is not None: + yield (src_chain, src_seq, target_chain, target_seq) + + def exists_path_from( + self, src_tuple: Tuple[int, int], target_tuple: Tuple[int, int], + ) -> bool: + """Checks if there is a path between the source chain ID/sequence and + target chain ID/sequence. + """ + src_chain, src_seq = src_tuple + target_chain, target_seq = target_tuple + + if src_chain == target_chain: + return target_seq <= src_seq + + links = self.get_links_between(src_chain, target_chain) + for link_start_seq, link_end_seq in links: + if link_start_seq <= src_seq and target_seq <= link_end_seq: + return True + + return False diff --git a/synapse/storage/databases/main/room.py b/synapse/storage/databases/main/room.py index 4650d0689b..284f2ce77c 100644 --- a/synapse/storage/databases/main/room.py +++ b/synapse/storage/databases/main/room.py @@ -84,7 +84,7 @@ class RoomWorkerStore(SQLBaseStore): return await self.db_pool.simple_select_one( table="rooms", keyvalues={"room_id": room_id}, - retcols=("room_id", "is_public", "creator"), + retcols=("room_id", "is_public", "creator", "has_auth_chain_index"), desc="get_room", allow_none=True, ) @@ -1166,6 +1166,37 @@ class RoomBackgroundUpdateStore(SQLBaseStore): # It's overridden by RoomStore for the synapse master. raise NotImplementedError() + async def has_auth_chain_index(self, room_id: str) -> bool: + """Check if the room has (or can have) a chain cover index. + + Defaults to True if we don't have an entry in `rooms` table nor any + events for the room. + """ + + has_auth_chain_index = await self.db_pool.simple_select_one_onecol( + table="rooms", + keyvalues={"room_id": room_id}, + retcol="has_auth_chain_index", + desc="has_auth_chain_index", + allow_none=True, + ) + + if has_auth_chain_index: + return True + + # It's possible that we already have events for the room in our DB + # without a corresponding room entry. If we do then we don't want to + # mark the room as having an auth chain cover index. + max_ordering = await self.db_pool.simple_select_one_onecol( + table="events", + keyvalues={"room_id": room_id}, + retcol="MAX(stream_ordering)", + allow_none=True, + desc="upsert_room_on_join", + ) + + return max_ordering is None + class RoomStore(RoomBackgroundUpdateStore, RoomWorkerStore, SearchStore): def __init__(self, database: DatabasePool, db_conn, hs): @@ -1179,12 +1210,21 @@ class RoomStore(RoomBackgroundUpdateStore, RoomWorkerStore, SearchStore): Called when we join a room over federation, and overwrites any room version currently in the table. """ + # It's possible that we already have events for the room in our DB + # without a corresponding room entry. If we do then we don't want to + # mark the room as having an auth chain cover index. + has_auth_chain_index = await self.has_auth_chain_index(room_id) + await self.db_pool.simple_upsert( desc="upsert_room_on_join", table="rooms", keyvalues={"room_id": room_id}, values={"room_version": room_version.identifier}, - insertion_values={"is_public": False, "creator": ""}, + insertion_values={ + "is_public": False, + "creator": "", + "has_auth_chain_index": has_auth_chain_index, + }, # rooms has a unique constraint on room_id, so no need to lock when doing an # emulated upsert. lock=False, @@ -1219,6 +1259,7 @@ class RoomStore(RoomBackgroundUpdateStore, RoomWorkerStore, SearchStore): "creator": room_creator_user_id, "is_public": is_public, "room_version": room_version.identifier, + "has_auth_chain_index": True, }, ) if is_public: @@ -1247,6 +1288,11 @@ class RoomStore(RoomBackgroundUpdateStore, RoomWorkerStore, SearchStore): When we receive an invite or any other event over federation that may relate to a room we are not in, store the version of the room if we don't already know the room version. """ + # It's possible that we already have events for the room in our DB + # without a corresponding room entry. If we do then we don't want to + # mark the room as having an auth chain cover index. + has_auth_chain_index = await self.has_auth_chain_index(room_id) + await self.db_pool.simple_upsert( desc="maybe_store_room_on_outlier_membership", table="rooms", @@ -1256,6 +1302,7 @@ class RoomStore(RoomBackgroundUpdateStore, RoomWorkerStore, SearchStore): "room_version": room_version.identifier, "is_public": False, "creator": "", + "has_auth_chain_index": has_auth_chain_index, }, # rooms has a unique constraint on room_id, so no need to lock when doing an # emulated upsert. diff --git a/synapse/storage/databases/main/schema/delta/59/04_event_auth_chains.sql b/synapse/storage/databases/main/schema/delta/59/04_event_auth_chains.sql new file mode 100644 index 0000000000..729196cfd5 --- /dev/null +++ b/synapse/storage/databases/main/schema/delta/59/04_event_auth_chains.sql @@ -0,0 +1,52 @@ +/* Copyright 2020 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. + */ + +-- See docs/auth_chain_difference_algorithm.md + +CREATE TABLE event_auth_chains ( + event_id TEXT PRIMARY KEY, + chain_id BIGINT NOT NULL, + sequence_number BIGINT NOT NULL +); + +CREATE UNIQUE INDEX event_auth_chains_c_seq_index ON event_auth_chains (chain_id, sequence_number); + + +CREATE TABLE event_auth_chain_links ( + origin_chain_id BIGINT NOT NULL, + origin_sequence_number BIGINT NOT NULL, + + target_chain_id BIGINT NOT NULL, + target_sequence_number BIGINT NOT NULL +); + + +CREATE INDEX event_auth_chain_links_idx ON event_auth_chain_links (origin_chain_id, target_chain_id); + + +-- Events that we have persisted but not calculated auth chains for, +-- e.g. out of band memberships (where we don't have the auth chain) +CREATE TABLE event_auth_chain_to_calculate ( + event_id TEXT PRIMARY KEY, + room_id TEXT NOT NULL, + type TEXT NOT NULL, + state_key TEXT NOT NULL +); + +CREATE INDEX event_auth_chain_to_calculate_rm_id ON event_auth_chain_to_calculate(room_id); + + +-- Whether we've calculated the above index for a room. +ALTER TABLE rooms ADD COLUMN has_auth_chain_index BOOLEAN; diff --git a/synapse/storage/databases/main/schema/delta/59/04_event_auth_chains.sql.postgres b/synapse/storage/databases/main/schema/delta/59/04_event_auth_chains.sql.postgres new file mode 100644 index 0000000000..e8a035bbeb --- /dev/null +++ b/synapse/storage/databases/main/schema/delta/59/04_event_auth_chains.sql.postgres @@ -0,0 +1,16 @@ +/* Copyright 2020 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. + */ + +CREATE SEQUENCE IF NOT EXISTS event_auth_chain_id; |