1298 lines
		
	
	
		
			46 KiB
		
	
	
	
		
			Python
		
	
	
			
		
		
	
	
			1298 lines
		
	
	
		
			46 KiB
		
	
	
	
		
			Python
		
	
	
| # -*- coding: utf-8 -*-
 | |
| # Copyright 2014-2016 OpenMarket Ltd
 | |
| # Copyright 2017 Vector Creations Ltd
 | |
| # Copyright 2018-2019 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.
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| # You may obtain a copy of the License at
 | |
| #
 | |
| #     http://www.apache.org/licenses/LICENSE-2.0
 | |
| #
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| # 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.
 | |
| 
 | |
| """ This module is responsible for getting events from the DB for pagination
 | |
| and event streaming.
 | |
| 
 | |
| The order it returns events in depend on whether we are streaming forwards or
 | |
| are paginating backwards. We do this because we want to handle out of order
 | |
| messages nicely, while still returning them in the correct order when we
 | |
| paginate bacwards.
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| 
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| This is implemented by keeping two ordering columns: stream_ordering and
 | |
| topological_ordering. Stream ordering is basically insertion/received order
 | |
| (except for events from backfill requests). The topological_ordering is a
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| weak ordering of events based on the pdu graph.
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| 
 | |
| This means that we have to have two different types of tokens, depending on
 | |
| what sort order was used:
 | |
|     - stream tokens are of the form: "s%d", which maps directly to the column
 | |
|     - topological tokems: "t%d-%d", where the integers map to the topological
 | |
|       and stream ordering columns respectively.
 | |
| """
 | |
| import abc
 | |
| import logging
 | |
| from collections import namedtuple
 | |
| from typing import TYPE_CHECKING, Dict, List, Optional, Set, Tuple
 | |
| 
 | |
| from twisted.internet import defer
 | |
| 
 | |
| from synapse.api.filtering import Filter
 | |
| from synapse.events import EventBase
 | |
| from synapse.logging.context import make_deferred_yieldable, run_in_background
 | |
| from synapse.storage._base import SQLBaseStore
 | |
| from synapse.storage.database import (
 | |
|     DatabasePool,
 | |
|     LoggingTransaction,
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|     make_in_list_sql_clause,
 | |
| )
 | |
| from synapse.storage.databases.main.events_worker import EventsWorkerStore
 | |
| from synapse.storage.engines import BaseDatabaseEngine, PostgresEngine
 | |
| from synapse.storage.util.id_generators import MultiWriterIdGenerator
 | |
| from synapse.types import Collection, PersistedEventPosition, RoomStreamToken
 | |
| from synapse.util.caches.descriptors import cached
 | |
| from synapse.util.caches.stream_change_cache import StreamChangeCache
 | |
| 
 | |
| if TYPE_CHECKING:
 | |
|     from synapse.server import HomeServer
 | |
| 
 | |
| logger = logging.getLogger(__name__)
 | |
| 
 | |
| 
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| MAX_STREAM_SIZE = 1000
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| 
 | |
| 
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| _STREAM_TOKEN = "stream"
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| _TOPOLOGICAL_TOKEN = "topological"
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| 
 | |
| 
 | |
| # Used as return values for pagination APIs
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| _EventDictReturn = namedtuple(
 | |
|     "_EventDictReturn", ("event_id", "topological_ordering", "stream_ordering")
 | |
| )
 | |
| 
 | |
| 
 | |
| def generate_pagination_where_clause(
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|     direction: str,
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|     column_names: Tuple[str, str],
 | |
|     from_token: Optional[Tuple[Optional[int], int]],
 | |
|     to_token: Optional[Tuple[Optional[int], int]],
 | |
|     engine: BaseDatabaseEngine,
 | |
| ) -> str:
 | |
|     """Creates an SQL expression to bound the columns by the pagination
 | |
|     tokens.
 | |
| 
 | |
|     For example creates an SQL expression like:
 | |
| 
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|         (6, 7) >= (topological_ordering, stream_ordering)
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|         AND (5, 3) < (topological_ordering, stream_ordering)
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| 
 | |
|     would be generated for dir=b, from_token=(6, 7) and to_token=(5, 3).
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| 
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|     Note that tokens are considered to be after the row they are in, e.g. if
 | |
|     a row A has a token T, then we consider A to be before T. This convention
 | |
|     is important when figuring out inequalities for the generated SQL, and
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|     produces the following result:
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|         - If paginating forwards then we exclude any rows matching the from
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|           token, but include those that match the to token.
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|         - If paginating backwards then we include any rows matching the from
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|           token, but include those that match the to token.
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| 
 | |
|     Args:
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|         direction: Whether we're paginating backwards("b") or forwards ("f").
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|         column_names: The column names to bound. Must *not* be user defined as
 | |
|             these get inserted directly into the SQL statement without escapes.
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|         from_token: The start point for the pagination. This is an exclusive
 | |
|             minimum bound if direction is "f", and an inclusive maximum bound if
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|             direction is "b".
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|         to_token: The endpoint point for the pagination. This is an inclusive
 | |
|             maximum bound if direction is "f", and an exclusive minimum bound if
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|             direction is "b".
 | |
|         engine: The database engine to generate the clauses for
 | |
| 
 | |
|     Returns:
 | |
|         The sql expression
 | |
|     """
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|     assert direction in ("b", "f")
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| 
 | |
|     where_clause = []
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|     if from_token:
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|         where_clause.append(
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|             _make_generic_sql_bound(
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|                 bound=">=" if direction == "b" else "<",
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|                 column_names=column_names,
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|                 values=from_token,
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|                 engine=engine,
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|             )
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|         )
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| 
 | |
|     if to_token:
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|         where_clause.append(
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|             _make_generic_sql_bound(
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|                 bound="<" if direction == "b" else ">=",
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|                 column_names=column_names,
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|                 values=to_token,
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|                 engine=engine,
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|             )
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|         )
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| 
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|     return " AND ".join(where_clause)
 | |
| 
 | |
| 
 | |
| def _make_generic_sql_bound(
 | |
|     bound: str,
 | |
|     column_names: Tuple[str, str],
 | |
|     values: Tuple[Optional[int], int],
 | |
|     engine: BaseDatabaseEngine,
 | |
| ) -> str:
 | |
|     """Create an SQL expression that bounds the given column names by the
 | |
|     values, e.g. create the equivalent of `(1, 2) < (col1, col2)`.
 | |
| 
 | |
|     Only works with two columns.
 | |
| 
 | |
|     Older versions of SQLite don't support that syntax so we have to expand it
 | |
|     out manually.
 | |
| 
 | |
|     Args:
 | |
|         bound: The comparison operator to use. One of ">", "<", ">=",
 | |
|             "<=", where the values are on the left and columns on the right.
 | |
|         names: The column names. Must *not* be user defined
 | |
|             as these get inserted directly into the SQL statement without
 | |
|             escapes.
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|         values: The values to bound the columns by. If
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|             the first value is None then only creates a bound on the second
 | |
|             column.
 | |
|         engine: The database engine to generate the SQL for
 | |
| 
 | |
|     Returns:
 | |
|         The SQL statement
 | |
|     """
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| 
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|     assert bound in (">", "<", ">=", "<=")
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| 
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|     name1, name2 = column_names
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|     val1, val2 = values
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| 
 | |
|     if val1 is None:
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|         val2 = int(val2)
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|         return "(%d %s %s)" % (val2, bound, name2)
 | |
| 
 | |
|     val1 = int(val1)
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|     val2 = int(val2)
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| 
 | |
|     if isinstance(engine, PostgresEngine):
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|         # Postgres doesn't optimise ``(x < a) OR (x=a AND y<b)`` as well
 | |
|         # as it optimises ``(x,y) < (a,b)`` on multicolumn indexes. So we
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|         # use the later form when running against postgres.
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|         return "((%d,%d) %s (%s,%s))" % (val1, val2, bound, name1, name2)
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| 
 | |
|     # We want to generate queries of e.g. the form:
 | |
|     #
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|     #   (val1 < name1 OR (val1 = name1 AND val2 <= name2))
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|     #
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|     # which is equivalent to (val1, val2) < (name1, name2)
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| 
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|     return """(
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|         {val1:d} {strict_bound} {name1}
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|         OR ({val1:d} = {name1} AND {val2:d} {bound} {name2})
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|     )""".format(
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|         name1=name1,
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|         val1=val1,
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|         name2=name2,
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|         val2=val2,
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|         strict_bound=bound[0],  # The first bound must always be strict equality here
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|         bound=bound,
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|     )
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| 
 | |
| 
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| def _filter_results(
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|     lower_token: Optional[RoomStreamToken],
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|     upper_token: Optional[RoomStreamToken],
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|     instance_name: str,
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|     topological_ordering: int,
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|     stream_ordering: int,
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| ) -> bool:
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|     """Returns True if the event persisted by the given instance at the given
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|     topological/stream_ordering falls between the two tokens (taking a None
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|     token to mean unbounded).
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| 
 | |
|     Used to filter results from fetching events in the DB against the given
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|     tokens. This is necessary to handle the case where the tokens include
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|     position maps, which we handle by fetching more than necessary from the DB
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|     and then filtering (rather than attempting to construct a complicated SQL
 | |
|     query).
 | |
|     """
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| 
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|     event_historical_tuple = (
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|         topological_ordering,
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|         stream_ordering,
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|     )
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| 
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|     if lower_token:
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|         if lower_token.topological is not None:
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|             # If these are historical tokens we compare the `(topological, stream)`
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|             # tuples.
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|             if event_historical_tuple <= lower_token.as_historical_tuple():
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|                 return False
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| 
 | |
|         else:
 | |
|             # If these are live tokens we compare the stream ordering against the
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|             # writers stream position.
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|             if stream_ordering <= lower_token.get_stream_pos_for_instance(
 | |
|                 instance_name
 | |
|             ):
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|                 return False
 | |
| 
 | |
|     if upper_token:
 | |
|         if upper_token.topological is not None:
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|             if upper_token.as_historical_tuple() < event_historical_tuple:
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|                 return False
 | |
|         else:
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|             if upper_token.get_stream_pos_for_instance(instance_name) < stream_ordering:
 | |
|                 return False
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| 
 | |
|     return True
 | |
| 
 | |
| 
 | |
| def filter_to_clause(event_filter: Optional[Filter]) -> Tuple[str, List[str]]:
 | |
|     # NB: This may create SQL clauses that don't optimise well (and we don't
 | |
|     # have indices on all possible clauses). E.g. it may create
 | |
|     # "room_id == X AND room_id != X", which postgres doesn't optimise.
 | |
| 
 | |
|     if not event_filter:
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|         return "", []
 | |
| 
 | |
|     clauses = []
 | |
|     args = []
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| 
 | |
|     if event_filter.types:
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|         clauses.append("(%s)" % " OR ".join("type = ?" for _ in event_filter.types))
 | |
|         args.extend(event_filter.types)
 | |
| 
 | |
|     for typ in event_filter.not_types:
 | |
|         clauses.append("type != ?")
 | |
|         args.append(typ)
 | |
| 
 | |
|     if event_filter.senders:
 | |
|         clauses.append("(%s)" % " OR ".join("sender = ?" for _ in event_filter.senders))
 | |
|         args.extend(event_filter.senders)
 | |
| 
 | |
|     for sender in event_filter.not_senders:
 | |
|         clauses.append("sender != ?")
 | |
|         args.append(sender)
 | |
| 
 | |
|     if event_filter.rooms:
 | |
|         clauses.append("(%s)" % " OR ".join("room_id = ?" for _ in event_filter.rooms))
 | |
|         args.extend(event_filter.rooms)
 | |
| 
 | |
|     for room_id in event_filter.not_rooms:
 | |
|         clauses.append("room_id != ?")
 | |
|         args.append(room_id)
 | |
| 
 | |
|     if event_filter.contains_url:
 | |
|         clauses.append("contains_url = ?")
 | |
|         args.append(event_filter.contains_url)
 | |
| 
 | |
|     # We're only applying the "labels" filter on the database query, because applying the
 | |
|     # "not_labels" filter via a SQL query is non-trivial. Instead, we let
 | |
|     # event_filter.check_fields apply it, which is not as efficient but makes the
 | |
|     # implementation simpler.
 | |
|     if event_filter.labels:
 | |
|         clauses.append("(%s)" % " OR ".join("label = ?" for _ in event_filter.labels))
 | |
|         args.extend(event_filter.labels)
 | |
| 
 | |
|     return " AND ".join(clauses), args
 | |
| 
 | |
| 
 | |
| class StreamWorkerStore(EventsWorkerStore, SQLBaseStore, metaclass=abc.ABCMeta):
 | |
|     """This is an abstract base class where subclasses must implement
 | |
|     `get_room_max_stream_ordering` and `get_room_min_stream_ordering`
 | |
|     which can be called in the initializer.
 | |
|     """
 | |
| 
 | |
|     def __init__(self, database: DatabasePool, db_conn, hs: "HomeServer"):
 | |
|         super().__init__(database, db_conn, hs)
 | |
| 
 | |
|         self._instance_name = hs.get_instance_name()
 | |
|         self._send_federation = hs.should_send_federation()
 | |
|         self._federation_shard_config = hs.config.worker.federation_shard_config
 | |
| 
 | |
|         # If we're a process that sends federation we may need to reset the
 | |
|         # `federation_stream_position` table to match the current sharding
 | |
|         # config. We don't do this now as otherwise two processes could conflict
 | |
|         # during startup which would cause one to die.
 | |
|         self._need_to_reset_federation_stream_positions = self._send_federation
 | |
| 
 | |
|         events_max = self.get_room_max_stream_ordering()
 | |
|         event_cache_prefill, min_event_val = self.db_pool.get_cache_dict(
 | |
|             db_conn,
 | |
|             "events",
 | |
|             entity_column="room_id",
 | |
|             stream_column="stream_ordering",
 | |
|             max_value=events_max,
 | |
|         )
 | |
|         self._events_stream_cache = StreamChangeCache(
 | |
|             "EventsRoomStreamChangeCache",
 | |
|             min_event_val,
 | |
|             prefilled_cache=event_cache_prefill,
 | |
|         )
 | |
|         self._membership_stream_cache = StreamChangeCache(
 | |
|             "MembershipStreamChangeCache", events_max
 | |
|         )
 | |
| 
 | |
|         self._stream_order_on_start = self.get_room_max_stream_ordering()
 | |
| 
 | |
|     @abc.abstractmethod
 | |
|     def get_room_max_stream_ordering(self) -> int:
 | |
|         raise NotImplementedError()
 | |
| 
 | |
|     @abc.abstractmethod
 | |
|     def get_room_min_stream_ordering(self) -> int:
 | |
|         raise NotImplementedError()
 | |
| 
 | |
|     def get_room_max_token(self) -> RoomStreamToken:
 | |
|         """Get a `RoomStreamToken` that marks the current maximum persisted
 | |
|         position of the events stream. Useful to get a token that represents
 | |
|         "now".
 | |
| 
 | |
|         The token returned is a "live" token that may have an instance_map
 | |
|         component.
 | |
|         """
 | |
| 
 | |
|         min_pos = self._stream_id_gen.get_current_token()
 | |
| 
 | |
|         positions = {}
 | |
|         if isinstance(self._stream_id_gen, MultiWriterIdGenerator):
 | |
|             # The `min_pos` is the minimum position that we know all instances
 | |
|             # have finished persisting to, so we only care about instances whose
 | |
|             # positions are ahead of that. (Instance positions can be behind the
 | |
|             # min position as there are times we can work out that the minimum
 | |
|             # position is ahead of the naive minimum across all current
 | |
|             # positions. See MultiWriterIdGenerator for details)
 | |
|             positions = {
 | |
|                 i: p
 | |
|                 for i, p in self._stream_id_gen.get_positions().items()
 | |
|                 if p > min_pos
 | |
|             }
 | |
| 
 | |
|         return RoomStreamToken(None, min_pos, positions)
 | |
| 
 | |
|     async def get_room_events_stream_for_rooms(
 | |
|         self,
 | |
|         room_ids: Collection[str],
 | |
|         from_key: RoomStreamToken,
 | |
|         to_key: RoomStreamToken,
 | |
|         limit: int = 0,
 | |
|         order: str = "DESC",
 | |
|     ) -> Dict[str, Tuple[List[EventBase], RoomStreamToken]]:
 | |
|         """Get new room events in stream ordering since `from_key`.
 | |
| 
 | |
|         Args:
 | |
|             room_ids
 | |
|             from_key: Token from which no events are returned before
 | |
|             to_key: Token from which no events are returned after. (This
 | |
|                 is typically the current stream token)
 | |
|             limit: Maximum number of events to return
 | |
|             order: Either "DESC" or "ASC". Determines which events are
 | |
|                 returned when the result is limited. If "DESC" then the most
 | |
|                 recent `limit` events are returned, otherwise returns the
 | |
|                 oldest `limit` events.
 | |
| 
 | |
|         Returns:
 | |
|             A map from room id to a tuple containing:
 | |
|                 - list of recent events in the room
 | |
|                 - stream ordering key for the start of the chunk of events returned.
 | |
|         """
 | |
|         room_ids = self._events_stream_cache.get_entities_changed(
 | |
|             room_ids, from_key.stream
 | |
|         )
 | |
| 
 | |
|         if not room_ids:
 | |
|             return {}
 | |
| 
 | |
|         results = {}
 | |
|         room_ids = list(room_ids)
 | |
|         for rm_ids in (room_ids[i : i + 20] for i in range(0, len(room_ids), 20)):
 | |
|             res = await make_deferred_yieldable(
 | |
|                 defer.gatherResults(
 | |
|                     [
 | |
|                         run_in_background(
 | |
|                             self.get_room_events_stream_for_room,
 | |
|                             room_id,
 | |
|                             from_key,
 | |
|                             to_key,
 | |
|                             limit,
 | |
|                             order=order,
 | |
|                         )
 | |
|                         for room_id in rm_ids
 | |
|                     ],
 | |
|                     consumeErrors=True,
 | |
|                 )
 | |
|             )
 | |
|             results.update(dict(zip(rm_ids, res)))
 | |
| 
 | |
|         return results
 | |
| 
 | |
|     def get_rooms_that_changed(
 | |
|         self, room_ids: Collection[str], from_key: RoomStreamToken
 | |
|     ) -> Set[str]:
 | |
|         """Given a list of rooms and a token, return rooms where there may have
 | |
|         been changes.
 | |
|         """
 | |
|         from_id = from_key.stream
 | |
|         return {
 | |
|             room_id
 | |
|             for room_id in room_ids
 | |
|             if self._events_stream_cache.has_entity_changed(room_id, from_id)
 | |
|         }
 | |
| 
 | |
|     async def get_room_events_stream_for_room(
 | |
|         self,
 | |
|         room_id: str,
 | |
|         from_key: RoomStreamToken,
 | |
|         to_key: RoomStreamToken,
 | |
|         limit: int = 0,
 | |
|         order: str = "DESC",
 | |
|     ) -> Tuple[List[EventBase], RoomStreamToken]:
 | |
|         """Get new room events in stream ordering since `from_key`.
 | |
| 
 | |
|         Args:
 | |
|             room_id
 | |
|             from_key: Token from which no events are returned before
 | |
|             to_key: Token from which no events are returned after. (This
 | |
|                 is typically the current stream token)
 | |
|             limit: Maximum number of events to return
 | |
|             order: Either "DESC" or "ASC". Determines which events are
 | |
|                 returned when the result is limited. If "DESC" then the most
 | |
|                 recent `limit` events are returned, otherwise returns the
 | |
|                 oldest `limit` events.
 | |
| 
 | |
|         Returns:
 | |
|             The list of events (in ascending order) and the token from the start
 | |
|             of the chunk of events returned.
 | |
|         """
 | |
|         if from_key == to_key:
 | |
|             return [], from_key
 | |
| 
 | |
|         has_changed = self._events_stream_cache.has_entity_changed(
 | |
|             room_id, from_key.stream
 | |
|         )
 | |
| 
 | |
|         if not has_changed:
 | |
|             return [], from_key
 | |
| 
 | |
|         def f(txn):
 | |
|             # To handle tokens with a non-empty instance_map we fetch more
 | |
|             # results than necessary and then filter down
 | |
|             min_from_id = from_key.stream
 | |
|             max_to_id = to_key.get_max_stream_pos()
 | |
| 
 | |
|             sql = """
 | |
|                 SELECT event_id, instance_name, topological_ordering, stream_ordering
 | |
|                 FROM events
 | |
|                 WHERE
 | |
|                     room_id = ?
 | |
|                     AND not outlier
 | |
|                     AND stream_ordering > ? AND stream_ordering <= ?
 | |
|                 ORDER BY stream_ordering %s LIMIT ?
 | |
|             """ % (
 | |
|                 order,
 | |
|             )
 | |
|             txn.execute(sql, (room_id, min_from_id, max_to_id, 2 * limit))
 | |
| 
 | |
|             rows = [
 | |
|                 _EventDictReturn(event_id, None, stream_ordering)
 | |
|                 for event_id, instance_name, topological_ordering, stream_ordering in txn
 | |
|                 if _filter_results(
 | |
|                     from_key,
 | |
|                     to_key,
 | |
|                     instance_name,
 | |
|                     topological_ordering,
 | |
|                     stream_ordering,
 | |
|                 )
 | |
|             ][:limit]
 | |
|             return rows
 | |
| 
 | |
|         rows = await self.db_pool.runInteraction("get_room_events_stream_for_room", f)
 | |
| 
 | |
|         ret = await self.get_events_as_list(
 | |
|             [r.event_id for r in rows], get_prev_content=True
 | |
|         )
 | |
| 
 | |
|         self._set_before_and_after(ret, rows, topo_order=False)
 | |
| 
 | |
|         if order.lower() == "desc":
 | |
|             ret.reverse()
 | |
| 
 | |
|         if rows:
 | |
|             key = RoomStreamToken(None, min(r.stream_ordering for r in rows))
 | |
|         else:
 | |
|             # Assume we didn't get anything because there was nothing to
 | |
|             # get.
 | |
|             key = from_key
 | |
| 
 | |
|         return ret, key
 | |
| 
 | |
|     async def get_membership_changes_for_user(
 | |
|         self, user_id: str, from_key: RoomStreamToken, to_key: RoomStreamToken
 | |
|     ) -> List[EventBase]:
 | |
|         if from_key == to_key:
 | |
|             return []
 | |
| 
 | |
|         if from_key:
 | |
|             has_changed = self._membership_stream_cache.has_entity_changed(
 | |
|                 user_id, int(from_key.stream)
 | |
|             )
 | |
|             if not has_changed:
 | |
|                 return []
 | |
| 
 | |
|         def f(txn):
 | |
|             # To handle tokens with a non-empty instance_map we fetch more
 | |
|             # results than necessary and then filter down
 | |
|             min_from_id = from_key.stream
 | |
|             max_to_id = to_key.get_max_stream_pos()
 | |
| 
 | |
|             sql = """
 | |
|                 SELECT m.event_id, instance_name, topological_ordering, stream_ordering
 | |
|                 FROM events AS e, room_memberships AS m
 | |
|                 WHERE e.event_id = m.event_id
 | |
|                     AND m.user_id = ?
 | |
|                     AND e.stream_ordering > ? AND e.stream_ordering <= ?
 | |
|                 ORDER BY e.stream_ordering ASC
 | |
|             """
 | |
|             txn.execute(sql, (user_id, min_from_id, max_to_id,))
 | |
| 
 | |
|             rows = [
 | |
|                 _EventDictReturn(event_id, None, stream_ordering)
 | |
|                 for event_id, instance_name, topological_ordering, stream_ordering in txn
 | |
|                 if _filter_results(
 | |
|                     from_key,
 | |
|                     to_key,
 | |
|                     instance_name,
 | |
|                     topological_ordering,
 | |
|                     stream_ordering,
 | |
|                 )
 | |
|             ]
 | |
| 
 | |
|             return rows
 | |
| 
 | |
|         rows = await self.db_pool.runInteraction("get_membership_changes_for_user", f)
 | |
| 
 | |
|         ret = await self.get_events_as_list(
 | |
|             [r.event_id for r in rows], get_prev_content=True
 | |
|         )
 | |
| 
 | |
|         self._set_before_and_after(ret, rows, topo_order=False)
 | |
| 
 | |
|         return ret
 | |
| 
 | |
|     async def get_recent_events_for_room(
 | |
|         self, room_id: str, limit: int, end_token: RoomStreamToken
 | |
|     ) -> Tuple[List[EventBase], RoomStreamToken]:
 | |
|         """Get the most recent events in the room in topological ordering.
 | |
| 
 | |
|         Args:
 | |
|             room_id
 | |
|             limit
 | |
|             end_token: The stream token representing now.
 | |
| 
 | |
|         Returns:
 | |
|             A list of events and a token pointing to the start of the returned
 | |
|             events. The events returned are in ascending order.
 | |
|         """
 | |
| 
 | |
|         rows, token = await self.get_recent_event_ids_for_room(
 | |
|             room_id, limit, end_token
 | |
|         )
 | |
| 
 | |
|         events = await self.get_events_as_list(
 | |
|             [r.event_id for r in rows], get_prev_content=True
 | |
|         )
 | |
| 
 | |
|         self._set_before_and_after(events, rows)
 | |
| 
 | |
|         return (events, token)
 | |
| 
 | |
|     async def get_recent_event_ids_for_room(
 | |
|         self, room_id: str, limit: int, end_token: RoomStreamToken
 | |
|     ) -> Tuple[List[_EventDictReturn], RoomStreamToken]:
 | |
|         """Get the most recent events in the room in topological ordering.
 | |
| 
 | |
|         Args:
 | |
|             room_id
 | |
|             limit
 | |
|             end_token: The stream token representing now.
 | |
| 
 | |
|         Returns:
 | |
|             A list of _EventDictReturn and a token pointing to the start of the
 | |
|             returned events. The events returned are in ascending order.
 | |
|         """
 | |
|         # Allow a zero limit here, and no-op.
 | |
|         if limit == 0:
 | |
|             return [], end_token
 | |
| 
 | |
|         rows, token = await self.db_pool.runInteraction(
 | |
|             "get_recent_event_ids_for_room",
 | |
|             self._paginate_room_events_txn,
 | |
|             room_id,
 | |
|             from_token=end_token,
 | |
|             limit=limit,
 | |
|         )
 | |
| 
 | |
|         # We want to return the results in ascending order.
 | |
|         rows.reverse()
 | |
| 
 | |
|         return rows, token
 | |
| 
 | |
|     async def get_room_event_before_stream_ordering(
 | |
|         self, room_id: str, stream_ordering: int
 | |
|     ) -> Optional[Tuple[int, int, str]]:
 | |
|         """Gets details of the first event in a room at or before a stream ordering
 | |
| 
 | |
|         Args:
 | |
|             room_id:
 | |
|             stream_ordering:
 | |
| 
 | |
|         Returns:
 | |
|             A tuple of (stream ordering, topological ordering, event_id)
 | |
|         """
 | |
| 
 | |
|         def _f(txn):
 | |
|             sql = (
 | |
|                 "SELECT stream_ordering, topological_ordering, event_id"
 | |
|                 " FROM events"
 | |
|                 " WHERE room_id = ? AND stream_ordering <= ?"
 | |
|                 " AND NOT outlier"
 | |
|                 " ORDER BY stream_ordering DESC"
 | |
|                 " LIMIT 1"
 | |
|             )
 | |
|             txn.execute(sql, (room_id, stream_ordering))
 | |
|             return txn.fetchone()
 | |
| 
 | |
|         return await self.db_pool.runInteraction(
 | |
|             "get_room_event_before_stream_ordering", _f
 | |
|         )
 | |
| 
 | |
|     async def get_room_events_max_id(self, room_id: Optional[str] = None) -> str:
 | |
|         """Returns the current token for rooms stream.
 | |
| 
 | |
|         By default, it returns the current global stream token. Specifying a
 | |
|         `room_id` causes it to return the current room specific topological
 | |
|         token.
 | |
|         """
 | |
|         token = self.get_room_max_stream_ordering()
 | |
|         if room_id is None:
 | |
|             return "s%d" % (token,)
 | |
|         else:
 | |
|             topo = await self.db_pool.runInteraction(
 | |
|                 "_get_max_topological_txn", self._get_max_topological_txn, room_id
 | |
|             )
 | |
|             return "t%d-%d" % (topo, token)
 | |
| 
 | |
|     def get_stream_id_for_event_txn(
 | |
|         self, txn: LoggingTransaction, event_id: str, allow_none=False,
 | |
|     ) -> int:
 | |
|         return self.db_pool.simple_select_one_onecol_txn(
 | |
|             txn=txn,
 | |
|             table="events",
 | |
|             keyvalues={"event_id": event_id},
 | |
|             retcol="stream_ordering",
 | |
|             allow_none=allow_none,
 | |
|         )
 | |
| 
 | |
|     async def get_position_for_event(self, event_id: str) -> PersistedEventPosition:
 | |
|         """Get the persisted position for an event
 | |
|         """
 | |
|         row = await self.db_pool.simple_select_one(
 | |
|             table="events",
 | |
|             keyvalues={"event_id": event_id},
 | |
|             retcols=("stream_ordering", "instance_name"),
 | |
|             desc="get_position_for_event",
 | |
|         )
 | |
| 
 | |
|         return PersistedEventPosition(
 | |
|             row["instance_name"] or "master", row["stream_ordering"]
 | |
|         )
 | |
| 
 | |
|     async def get_topological_token_for_event(self, event_id: str) -> RoomStreamToken:
 | |
|         """The stream token for an event
 | |
|         Args:
 | |
|             event_id: The id of the event to look up a stream token for.
 | |
|         Raises:
 | |
|             StoreError if the event wasn't in the database.
 | |
|         Returns:
 | |
|             A `RoomStreamToken` topological token.
 | |
|         """
 | |
|         row = await self.db_pool.simple_select_one(
 | |
|             table="events",
 | |
|             keyvalues={"event_id": event_id},
 | |
|             retcols=("stream_ordering", "topological_ordering"),
 | |
|             desc="get_topological_token_for_event",
 | |
|         )
 | |
|         return RoomStreamToken(row["topological_ordering"], row["stream_ordering"])
 | |
| 
 | |
|     async def get_current_topological_token(self, room_id: str, stream_key: int) -> int:
 | |
|         """Gets the topological token in a room after or at the given stream
 | |
|         ordering.
 | |
| 
 | |
|         Args:
 | |
|             room_id
 | |
|             stream_key
 | |
|         """
 | |
|         sql = (
 | |
|             "SELECT coalesce(MIN(topological_ordering), 0) FROM events"
 | |
|             " WHERE room_id = ? AND stream_ordering >= ?"
 | |
|         )
 | |
|         row = await self.db_pool.execute(
 | |
|             "get_current_topological_token", None, sql, room_id, stream_key
 | |
|         )
 | |
|         return row[0][0] if row else 0
 | |
| 
 | |
|     def _get_max_topological_txn(self, txn: LoggingTransaction, room_id: str) -> int:
 | |
|         txn.execute(
 | |
|             "SELECT MAX(topological_ordering) FROM events WHERE room_id = ?",
 | |
|             (room_id,),
 | |
|         )
 | |
| 
 | |
|         rows = txn.fetchall()
 | |
|         return rows[0][0] if rows else 0
 | |
| 
 | |
|     @staticmethod
 | |
|     def _set_before_and_after(
 | |
|         events: List[EventBase], rows: List[_EventDictReturn], topo_order: bool = True
 | |
|     ):
 | |
|         """Inserts ordering information to events' internal metadata from
 | |
|         the DB rows.
 | |
| 
 | |
|         Args:
 | |
|             events
 | |
|             rows
 | |
|             topo_order: Whether the events were ordered topologically or by stream
 | |
|                 ordering. If true then all rows should have a non null
 | |
|                 topological_ordering.
 | |
|         """
 | |
|         for event, row in zip(events, rows):
 | |
|             stream = row.stream_ordering
 | |
|             if topo_order and row.topological_ordering:
 | |
|                 topo = row.topological_ordering
 | |
|             else:
 | |
|                 topo = None
 | |
|             internal = event.internal_metadata
 | |
|             internal.before = RoomStreamToken(topo, stream - 1)
 | |
|             internal.after = RoomStreamToken(topo, stream)
 | |
|             internal.order = (int(topo) if topo else 0, int(stream))
 | |
| 
 | |
|     async def get_events_around(
 | |
|         self,
 | |
|         room_id: str,
 | |
|         event_id: str,
 | |
|         before_limit: int,
 | |
|         after_limit: int,
 | |
|         event_filter: Optional[Filter] = None,
 | |
|     ) -> dict:
 | |
|         """Retrieve events and pagination tokens around a given event in a
 | |
|         room.
 | |
|         """
 | |
| 
 | |
|         results = await self.db_pool.runInteraction(
 | |
|             "get_events_around",
 | |
|             self._get_events_around_txn,
 | |
|             room_id,
 | |
|             event_id,
 | |
|             before_limit,
 | |
|             after_limit,
 | |
|             event_filter,
 | |
|         )
 | |
| 
 | |
|         events_before = await self.get_events_as_list(
 | |
|             list(results["before"]["event_ids"]), get_prev_content=True
 | |
|         )
 | |
| 
 | |
|         events_after = await self.get_events_as_list(
 | |
|             list(results["after"]["event_ids"]), get_prev_content=True
 | |
|         )
 | |
| 
 | |
|         return {
 | |
|             "events_before": events_before,
 | |
|             "events_after": events_after,
 | |
|             "start": results["before"]["token"],
 | |
|             "end": results["after"]["token"],
 | |
|         }
 | |
| 
 | |
|     def _get_events_around_txn(
 | |
|         self,
 | |
|         txn: LoggingTransaction,
 | |
|         room_id: str,
 | |
|         event_id: str,
 | |
|         before_limit: int,
 | |
|         after_limit: int,
 | |
|         event_filter: Optional[Filter],
 | |
|     ) -> dict:
 | |
|         """Retrieves event_ids and pagination tokens around a given event in a
 | |
|         room.
 | |
| 
 | |
|         Args:
 | |
|             room_id
 | |
|             event_id
 | |
|             before_limit
 | |
|             after_limit
 | |
|             event_filter
 | |
| 
 | |
|         Returns:
 | |
|             dict
 | |
|         """
 | |
| 
 | |
|         results = self.db_pool.simple_select_one_txn(
 | |
|             txn,
 | |
|             "events",
 | |
|             keyvalues={"event_id": event_id, "room_id": room_id},
 | |
|             retcols=["stream_ordering", "topological_ordering"],
 | |
|         )
 | |
| 
 | |
|         # This cannot happen as `allow_none=False`.
 | |
|         assert results is not None
 | |
| 
 | |
|         # Paginating backwards includes the event at the token, but paginating
 | |
|         # forward doesn't.
 | |
|         before_token = RoomStreamToken(
 | |
|             results["topological_ordering"] - 1, results["stream_ordering"]
 | |
|         )
 | |
| 
 | |
|         after_token = RoomStreamToken(
 | |
|             results["topological_ordering"], results["stream_ordering"]
 | |
|         )
 | |
| 
 | |
|         rows, start_token = self._paginate_room_events_txn(
 | |
|             txn,
 | |
|             room_id,
 | |
|             before_token,
 | |
|             direction="b",
 | |
|             limit=before_limit,
 | |
|             event_filter=event_filter,
 | |
|         )
 | |
|         events_before = [r.event_id for r in rows]
 | |
| 
 | |
|         rows, end_token = self._paginate_room_events_txn(
 | |
|             txn,
 | |
|             room_id,
 | |
|             after_token,
 | |
|             direction="f",
 | |
|             limit=after_limit,
 | |
|             event_filter=event_filter,
 | |
|         )
 | |
|         events_after = [r.event_id for r in rows]
 | |
| 
 | |
|         return {
 | |
|             "before": {"event_ids": events_before, "token": start_token},
 | |
|             "after": {"event_ids": events_after, "token": end_token},
 | |
|         }
 | |
| 
 | |
|     async def get_all_new_events_stream(
 | |
|         self, from_id: int, current_id: int, limit: int
 | |
|     ) -> Tuple[int, List[EventBase]]:
 | |
|         """Get all new events
 | |
| 
 | |
|          Returns all events with from_id < stream_ordering <= current_id.
 | |
| 
 | |
|          Args:
 | |
|              from_id:  the stream_ordering of the last event we processed
 | |
|              current_id:  the stream_ordering of the most recently processed event
 | |
|              limit: the maximum number of events to return
 | |
| 
 | |
|          Returns:
 | |
|              A tuple of (next_id, events), where `next_id` is the next value to
 | |
|              pass as `from_id` (it will either be the stream_ordering of the
 | |
|              last returned event, or, if fewer than `limit` events were found,
 | |
|              the `current_id`).
 | |
|          """
 | |
| 
 | |
|         def get_all_new_events_stream_txn(txn):
 | |
|             sql = (
 | |
|                 "SELECT e.stream_ordering, e.event_id"
 | |
|                 " FROM events AS e"
 | |
|                 " WHERE"
 | |
|                 " ? < e.stream_ordering AND e.stream_ordering <= ?"
 | |
|                 " ORDER BY e.stream_ordering ASC"
 | |
|                 " LIMIT ?"
 | |
|             )
 | |
| 
 | |
|             txn.execute(sql, (from_id, current_id, limit))
 | |
|             rows = txn.fetchall()
 | |
| 
 | |
|             upper_bound = current_id
 | |
|             if len(rows) == limit:
 | |
|                 upper_bound = rows[-1][0]
 | |
| 
 | |
|             return upper_bound, [row[1] for row in rows]
 | |
| 
 | |
|         upper_bound, event_ids = await self.db_pool.runInteraction(
 | |
|             "get_all_new_events_stream", get_all_new_events_stream_txn
 | |
|         )
 | |
| 
 | |
|         events = await self.get_events_as_list(event_ids)
 | |
| 
 | |
|         return upper_bound, events
 | |
| 
 | |
|     async def get_federation_out_pos(self, typ: str) -> int:
 | |
|         if self._need_to_reset_federation_stream_positions:
 | |
|             await self.db_pool.runInteraction(
 | |
|                 "_reset_federation_positions_txn", self._reset_federation_positions_txn
 | |
|             )
 | |
|             self._need_to_reset_federation_stream_positions = False
 | |
| 
 | |
|         return await self.db_pool.simple_select_one_onecol(
 | |
|             table="federation_stream_position",
 | |
|             retcol="stream_id",
 | |
|             keyvalues={"type": typ, "instance_name": self._instance_name},
 | |
|             desc="get_federation_out_pos",
 | |
|         )
 | |
| 
 | |
|     async def update_federation_out_pos(self, typ: str, stream_id: int) -> None:
 | |
|         if self._need_to_reset_federation_stream_positions:
 | |
|             await self.db_pool.runInteraction(
 | |
|                 "_reset_federation_positions_txn", self._reset_federation_positions_txn
 | |
|             )
 | |
|             self._need_to_reset_federation_stream_positions = False
 | |
| 
 | |
|         await self.db_pool.simple_update_one(
 | |
|             table="federation_stream_position",
 | |
|             keyvalues={"type": typ, "instance_name": self._instance_name},
 | |
|             updatevalues={"stream_id": stream_id},
 | |
|             desc="update_federation_out_pos",
 | |
|         )
 | |
| 
 | |
|     def _reset_federation_positions_txn(self, txn: LoggingTransaction) -> None:
 | |
|         """Fiddles with the `federation_stream_position` table to make it match
 | |
|         the configured federation sender instances during start up.
 | |
|         """
 | |
| 
 | |
|         # The federation sender instances may have changed, so we need to
 | |
|         # massage the `federation_stream_position` table to have a row per type
 | |
|         # per instance sending federation. If there is a mismatch we update the
 | |
|         # table with the correct rows using the *minimum* stream ID seen. This
 | |
|         # may result in resending of events/EDUs to remote servers, but that is
 | |
|         # preferable to dropping them.
 | |
| 
 | |
|         if not self._send_federation:
 | |
|             return
 | |
| 
 | |
|         # Pull out the configured instances. If we don't have a shard config then
 | |
|         # we assume that we're the only instance sending.
 | |
|         configured_instances = self._federation_shard_config.instances
 | |
|         if not configured_instances:
 | |
|             configured_instances = [self._instance_name]
 | |
|         elif self._instance_name not in configured_instances:
 | |
|             return
 | |
| 
 | |
|         instances_in_table = self.db_pool.simple_select_onecol_txn(
 | |
|             txn,
 | |
|             table="federation_stream_position",
 | |
|             keyvalues={},
 | |
|             retcol="instance_name",
 | |
|         )
 | |
| 
 | |
|         if set(instances_in_table) == set(configured_instances):
 | |
|             # Nothing to do
 | |
|             return
 | |
| 
 | |
|         sql = """
 | |
|             SELECT type, MIN(stream_id) FROM federation_stream_position
 | |
|             GROUP BY type
 | |
|         """
 | |
|         txn.execute(sql)
 | |
|         min_positions = {typ: pos for typ, pos in txn}  # Map from type -> min position
 | |
| 
 | |
|         # Ensure we do actually have some values here
 | |
|         assert set(min_positions) == {"federation", "events"}
 | |
| 
 | |
|         sql = """
 | |
|             DELETE FROM federation_stream_position
 | |
|             WHERE NOT (%s)
 | |
|         """
 | |
|         clause, args = make_in_list_sql_clause(
 | |
|             txn.database_engine, "instance_name", configured_instances
 | |
|         )
 | |
|         txn.execute(sql % (clause,), args)
 | |
| 
 | |
|         for typ, stream_id in min_positions.items():
 | |
|             self.db_pool.simple_upsert_txn(
 | |
|                 txn,
 | |
|                 table="federation_stream_position",
 | |
|                 keyvalues={"type": typ, "instance_name": self._instance_name},
 | |
|                 values={"stream_id": stream_id},
 | |
|             )
 | |
| 
 | |
|     def has_room_changed_since(self, room_id: str, stream_id: int) -> bool:
 | |
|         return self._events_stream_cache.has_entity_changed(room_id, stream_id)
 | |
| 
 | |
|     def _paginate_room_events_txn(
 | |
|         self,
 | |
|         txn: LoggingTransaction,
 | |
|         room_id: str,
 | |
|         from_token: RoomStreamToken,
 | |
|         to_token: Optional[RoomStreamToken] = None,
 | |
|         direction: str = "b",
 | |
|         limit: int = -1,
 | |
|         event_filter: Optional[Filter] = None,
 | |
|     ) -> Tuple[List[_EventDictReturn], RoomStreamToken]:
 | |
|         """Returns list of events before or after a given token.
 | |
| 
 | |
|         Args:
 | |
|             txn
 | |
|             room_id
 | |
|             from_token: The token used to stream from
 | |
|             to_token: A token which if given limits the results to only those before
 | |
|             direction: Either 'b' or 'f' to indicate whether we are paginating
 | |
|                 forwards or backwards from `from_key`.
 | |
|             limit: The maximum number of events to return.
 | |
|             event_filter: If provided filters the events to
 | |
|                 those that match the filter.
 | |
| 
 | |
|         Returns:
 | |
|             A list of _EventDictReturn and a token that points to the end of the
 | |
|             result set. If no events are returned then the end of the stream has
 | |
|             been reached (i.e. there are no events between `from_token` and
 | |
|             `to_token`), or `limit` is zero.
 | |
|         """
 | |
| 
 | |
|         assert int(limit) >= 0
 | |
| 
 | |
|         # Tokens really represent positions between elements, but we use
 | |
|         # the convention of pointing to the event before the gap. Hence
 | |
|         # we have a bit of asymmetry when it comes to equalities.
 | |
|         args = [False, room_id]
 | |
|         if direction == "b":
 | |
|             order = "DESC"
 | |
|         else:
 | |
|             order = "ASC"
 | |
| 
 | |
|         # The bounds for the stream tokens are complicated by the fact
 | |
|         # that we need to handle the instance_map part of the tokens. We do this
 | |
|         # by fetching all events between the min stream token and the maximum
 | |
|         # stream token (as returned by `RoomStreamToken.get_max_stream_pos`) and
 | |
|         # then filtering the results.
 | |
|         if from_token.topological is not None:
 | |
|             from_bound = (
 | |
|                 from_token.as_historical_tuple()
 | |
|             )  # type: Tuple[Optional[int], int]
 | |
|         elif direction == "b":
 | |
|             from_bound = (
 | |
|                 None,
 | |
|                 from_token.get_max_stream_pos(),
 | |
|             )
 | |
|         else:
 | |
|             from_bound = (
 | |
|                 None,
 | |
|                 from_token.stream,
 | |
|             )
 | |
| 
 | |
|         to_bound = None  # type: Optional[Tuple[Optional[int], int]]
 | |
|         if to_token:
 | |
|             if to_token.topological is not None:
 | |
|                 to_bound = to_token.as_historical_tuple()
 | |
|             elif direction == "b":
 | |
|                 to_bound = (
 | |
|                     None,
 | |
|                     to_token.stream,
 | |
|                 )
 | |
|             else:
 | |
|                 to_bound = (
 | |
|                     None,
 | |
|                     to_token.get_max_stream_pos(),
 | |
|                 )
 | |
| 
 | |
|         bounds = generate_pagination_where_clause(
 | |
|             direction=direction,
 | |
|             column_names=("topological_ordering", "stream_ordering"),
 | |
|             from_token=from_bound,
 | |
|             to_token=to_bound,
 | |
|             engine=self.database_engine,
 | |
|         )
 | |
| 
 | |
|         filter_clause, filter_args = filter_to_clause(event_filter)
 | |
| 
 | |
|         if filter_clause:
 | |
|             bounds += " AND " + filter_clause
 | |
|             args.extend(filter_args)
 | |
| 
 | |
|         # We fetch more events as we'll filter the result set
 | |
|         args.append(int(limit) * 2)
 | |
| 
 | |
|         select_keywords = "SELECT"
 | |
|         join_clause = ""
 | |
|         if event_filter and event_filter.labels:
 | |
|             # If we're not filtering on a label, then joining on event_labels will
 | |
|             # return as many row for a single event as the number of labels it has. To
 | |
|             # avoid this, only join if we're filtering on at least one label.
 | |
|             join_clause = """
 | |
|                 LEFT JOIN event_labels
 | |
|                 USING (event_id, room_id, topological_ordering)
 | |
|             """
 | |
|             if len(event_filter.labels) > 1:
 | |
|                 # Using DISTINCT in this SELECT query is quite expensive, because it
 | |
|                 # requires the engine to sort on the entire (not limited) result set,
 | |
|                 # i.e. the entire events table. We only need to use it when we're
 | |
|                 # filtering on more than two labels, because that's the only scenario
 | |
|                 # in which we can possibly to get multiple times the same event ID in
 | |
|                 # the results.
 | |
|                 select_keywords += "DISTINCT"
 | |
| 
 | |
|         sql = """
 | |
|             %(select_keywords)s
 | |
|                 event_id, instance_name,
 | |
|                 topological_ordering, stream_ordering
 | |
|             FROM events
 | |
|             %(join_clause)s
 | |
|             WHERE outlier = ? AND room_id = ? AND %(bounds)s
 | |
|             ORDER BY topological_ordering %(order)s,
 | |
|             stream_ordering %(order)s LIMIT ?
 | |
|         """ % {
 | |
|             "select_keywords": select_keywords,
 | |
|             "join_clause": join_clause,
 | |
|             "bounds": bounds,
 | |
|             "order": order,
 | |
|         }
 | |
| 
 | |
|         txn.execute(sql, args)
 | |
| 
 | |
|         # Filter the result set.
 | |
|         rows = [
 | |
|             _EventDictReturn(event_id, topological_ordering, stream_ordering)
 | |
|             for event_id, instance_name, topological_ordering, stream_ordering in txn
 | |
|             if _filter_results(
 | |
|                 lower_token=to_token if direction == "b" else from_token,
 | |
|                 upper_token=from_token if direction == "b" else to_token,
 | |
|                 instance_name=instance_name,
 | |
|                 topological_ordering=topological_ordering,
 | |
|                 stream_ordering=stream_ordering,
 | |
|             )
 | |
|         ][:limit]
 | |
| 
 | |
|         if rows:
 | |
|             topo = rows[-1].topological_ordering
 | |
|             toke = rows[-1].stream_ordering
 | |
|             if direction == "b":
 | |
|                 # Tokens are positions between events.
 | |
|                 # This token points *after* the last event in the chunk.
 | |
|                 # We need it to point to the event before it in the chunk
 | |
|                 # when we are going backwards so we subtract one from the
 | |
|                 # stream part.
 | |
|                 toke -= 1
 | |
|             next_token = RoomStreamToken(topo, toke)
 | |
|         else:
 | |
|             # TODO (erikj): We should work out what to do here instead.
 | |
|             next_token = to_token if to_token else from_token
 | |
| 
 | |
|         return rows, next_token
 | |
| 
 | |
|     async def paginate_room_events(
 | |
|         self,
 | |
|         room_id: str,
 | |
|         from_key: RoomStreamToken,
 | |
|         to_key: Optional[RoomStreamToken] = None,
 | |
|         direction: str = "b",
 | |
|         limit: int = -1,
 | |
|         event_filter: Optional[Filter] = None,
 | |
|     ) -> Tuple[List[EventBase], RoomStreamToken]:
 | |
|         """Returns list of events before or after a given token.
 | |
| 
 | |
|         Args:
 | |
|             room_id
 | |
|             from_key: The token used to stream from
 | |
|             to_key: A token which if given limits the results to only those before
 | |
|             direction: Either 'b' or 'f' to indicate whether we are paginating
 | |
|                 forwards or backwards from `from_key`.
 | |
|             limit: The maximum number of events to return.
 | |
|             event_filter: If provided filters the events to those that match the filter.
 | |
| 
 | |
|         Returns:
 | |
|             The results as a list of events and a token that points to the end
 | |
|             of the result set. If no events are returned then the end of the
 | |
|             stream has been reached (i.e. there are no events between `from_key`
 | |
|             and `to_key`).
 | |
|         """
 | |
| 
 | |
|         rows, token = await self.db_pool.runInteraction(
 | |
|             "paginate_room_events",
 | |
|             self._paginate_room_events_txn,
 | |
|             room_id,
 | |
|             from_key,
 | |
|             to_key,
 | |
|             direction,
 | |
|             limit,
 | |
|             event_filter,
 | |
|         )
 | |
| 
 | |
|         events = await self.get_events_as_list(
 | |
|             [r.event_id for r in rows], get_prev_content=True
 | |
|         )
 | |
| 
 | |
|         self._set_before_and_after(events, rows)
 | |
| 
 | |
|         return (events, token)
 | |
| 
 | |
|     @cached()
 | |
|     async def get_id_for_instance(self, instance_name: str) -> int:
 | |
|         """Get a unique, immutable ID that corresponds to the given Synapse worker instance.
 | |
|         """
 | |
| 
 | |
|         def _get_id_for_instance_txn(txn):
 | |
|             instance_id = self.db_pool.simple_select_one_onecol_txn(
 | |
|                 txn,
 | |
|                 table="instance_map",
 | |
|                 keyvalues={"instance_name": instance_name},
 | |
|                 retcol="instance_id",
 | |
|                 allow_none=True,
 | |
|             )
 | |
|             if instance_id is not None:
 | |
|                 return instance_id
 | |
| 
 | |
|             # If we don't have an entry upsert one.
 | |
|             #
 | |
|             # We could do this before the first check, and rely on the cache for
 | |
|             # efficiency, but each UPSERT causes the next ID to increment which
 | |
|             # can quickly bloat the size of the generated IDs for new instances.
 | |
|             self.db_pool.simple_upsert_txn(
 | |
|                 txn,
 | |
|                 table="instance_map",
 | |
|                 keyvalues={"instance_name": instance_name},
 | |
|                 values={},
 | |
|             )
 | |
| 
 | |
|             return self.db_pool.simple_select_one_onecol_txn(
 | |
|                 txn,
 | |
|                 table="instance_map",
 | |
|                 keyvalues={"instance_name": instance_name},
 | |
|                 retcol="instance_id",
 | |
|             )
 | |
| 
 | |
|         return await self.db_pool.runInteraction(
 | |
|             "get_id_for_instance", _get_id_for_instance_txn
 | |
|         )
 | |
| 
 | |
|     @cached()
 | |
|     async def get_name_from_instance_id(self, instance_id: int) -> str:
 | |
|         """Get the instance name from an ID previously returned by
 | |
|         `get_id_for_instance`.
 | |
|         """
 | |
| 
 | |
|         return await self.db_pool.simple_select_one_onecol(
 | |
|             table="instance_map",
 | |
|             keyvalues={"instance_id": instance_id},
 | |
|             retcol="instance_name",
 | |
|             desc="get_name_from_instance_id",
 | |
|         )
 | |
| 
 | |
| 
 | |
| class StreamStore(StreamWorkerStore):
 | |
|     def get_room_max_stream_ordering(self) -> int:
 | |
|         return self._stream_id_gen.get_current_token()
 | |
| 
 | |
|     def get_room_min_stream_ordering(self) -> int:
 | |
|         return self._backfill_id_gen.get_current_token()
 |