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Diffstat (limited to 'synapse/storage/relations.py')
| -rw-r--r-- | synapse/storage/relations.py | 434 |
1 files changed, 434 insertions, 0 deletions
diff --git a/synapse/storage/relations.py b/synapse/storage/relations.py new file mode 100644 index 0000000000..63e6185ee3 --- /dev/null +++ b/synapse/storage/relations.py @@ -0,0 +1,434 @@ +# -*- coding: utf-8 -*- +# Copyright 2019 New Vector Ltd +# +# Licensed under the Apache License, Version 2.0 (the "License"); +# you may not use this file except in compliance with the License. +# You may obtain a copy of the License at +# +# http://www.apache.org/licenses/LICENSE-2.0 +# +# Unless required by applicable law or agreed to in writing, software +# distributed under the License is distributed on an "AS IS" BASIS, +# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +# See the License for the specific language governing permissions and +# limitations under the License. + +import logging + +import attr + +from twisted.internet import defer + +from synapse.api.constants import RelationTypes +from synapse.api.errors import SynapseError +from synapse.storage._base import SQLBaseStore +from synapse.storage.stream import generate_pagination_where_clause +from synapse.util.caches.descriptors import cached, cachedInlineCallbacks + +logger = logging.getLogger(__name__) + + +@attr.s +class PaginationChunk(object): + """Returned by relation pagination APIs. + + Attributes: + chunk (list): The rows returned by pagination + next_batch (Any|None): Token to fetch next set of results with, if + None then there are no more results. + prev_batch (Any|None): Token to fetch previous set of results with, if + None then there are no previous results. + """ + + chunk = attr.ib() + next_batch = attr.ib(default=None) + prev_batch = attr.ib(default=None) + + def to_dict(self): + d = {"chunk": self.chunk} + + if self.next_batch: + d["next_batch"] = self.next_batch.to_string() + + if self.prev_batch: + d["prev_batch"] = self.prev_batch.to_string() + + return d + + +@attr.s(frozen=True, slots=True) +class RelationPaginationToken(object): + """Pagination token for relation pagination API. + + As the results are order by topological ordering, we can use the + `topological_ordering` and `stream_ordering` fields of the events at the + boundaries of the chunk as pagination tokens. + + Attributes: + topological (int): The topological ordering of the boundary event + stream (int): The stream ordering of the boundary event. + """ + + topological = attr.ib() + stream = attr.ib() + + @staticmethod + def from_string(string): + try: + t, s = string.split("-") + return RelationPaginationToken(int(t), int(s)) + except ValueError: + raise SynapseError(400, "Invalid token") + + def to_string(self): + return "%d-%d" % (self.topological, self.stream) + + def as_tuple(self): + return attr.astuple(self) + + +@attr.s(frozen=True, slots=True) +class AggregationPaginationToken(object): + """Pagination token for relation aggregation pagination API. + + As the results are order by count and then MAX(stream_ordering) of the + aggregation groups, we can just use them as our pagination token. + + Attributes: + count (int): The count of relations in the boundar group. + stream (int): The MAX stream ordering in the boundary group. + """ + + count = attr.ib() + stream = attr.ib() + + @staticmethod + def from_string(string): + try: + c, s = string.split("-") + return AggregationPaginationToken(int(c), int(s)) + except ValueError: + raise SynapseError(400, "Invalid token") + + def to_string(self): + return "%d-%d" % (self.count, self.stream) + + def as_tuple(self): + return attr.astuple(self) + + +class RelationsWorkerStore(SQLBaseStore): + @cached(tree=True) + def get_relations_for_event( + self, + event_id, + relation_type=None, + event_type=None, + aggregation_key=None, + limit=5, + direction="b", + from_token=None, + to_token=None, + ): + """Get a list of relations for an event, ordered by topological ordering. + + Args: + event_id (str): Fetch events that relate to this event ID. + relation_type (str|None): Only fetch events with this relation + type, if given. + event_type (str|None): Only fetch events with this event type, if + given. + aggregation_key (str|None): Only fetch events with this aggregation + key, if given. + limit (int): Only fetch the most recent `limit` events. + direction (str): Whether to fetch the most recent first (`"b"`) or + the oldest first (`"f"`). + from_token (RelationPaginationToken|None): Fetch rows from the given + token, or from the start if None. + to_token (RelationPaginationToken|None): Fetch rows up to the given + token, or up to the end if None. + + Returns: + Deferred[PaginationChunk]: List of event IDs that match relations + requested. The rows are of the form `{"event_id": "..."}`. + """ + + where_clause = ["relates_to_id = ?"] + where_args = [event_id] + + if relation_type is not None: + where_clause.append("relation_type = ?") + where_args.append(relation_type) + + if event_type is not None: + where_clause.append("type = ?") + where_args.append(event_type) + + if aggregation_key: + where_clause.append("aggregation_key = ?") + where_args.append(aggregation_key) + + pagination_clause = generate_pagination_where_clause( + direction=direction, + column_names=("topological_ordering", "stream_ordering"), + from_token=attr.astuple(from_token) if from_token else None, + to_token=attr.astuple(to_token) if to_token else None, + engine=self.database_engine, + ) + + if pagination_clause: + where_clause.append(pagination_clause) + + if direction == "b": + order = "DESC" + else: + order = "ASC" + + sql = """ + SELECT event_id, topological_ordering, stream_ordering + FROM event_relations + INNER JOIN events USING (event_id) + WHERE %s + ORDER BY topological_ordering %s, stream_ordering %s + LIMIT ? + """ % ( + " AND ".join(where_clause), + order, + order, + ) + + def _get_recent_references_for_event_txn(txn): + txn.execute(sql, where_args + [limit + 1]) + + last_topo_id = None + last_stream_id = None + events = [] + for row in txn: + events.append({"event_id": row[0]}) + last_topo_id = row[1] + last_stream_id = row[2] + + next_batch = None + if len(events) > limit and last_topo_id and last_stream_id: + next_batch = RelationPaginationToken(last_topo_id, last_stream_id) + + return PaginationChunk( + chunk=list(events[:limit]), next_batch=next_batch, prev_batch=from_token + ) + + return self.runInteraction( + "get_recent_references_for_event", _get_recent_references_for_event_txn + ) + + @cached(tree=True) + def get_aggregation_groups_for_event( + self, + event_id, + event_type=None, + limit=5, + direction="b", + from_token=None, + to_token=None, + ): + """Get a list of annotations on the event, grouped by event type and + aggregation key, sorted by count. + + This is used e.g. to get the what and how many reactions have happend + on an event. + + Args: + event_id (str): Fetch events that relate to this event ID. + event_type (str|None): Only fetch events with this event type, if + given. + limit (int): Only fetch the `limit` groups. + direction (str): Whether to fetch the highest count first (`"b"`) or + the lowest count first (`"f"`). + from_token (AggregationPaginationToken|None): Fetch rows from the + given token, or from the start if None. + to_token (AggregationPaginationToken|None): Fetch rows up to the + given token, or up to the end if None. + + + Returns: + Deferred[PaginationChunk]: List of groups of annotations that + match. Each row is a dict with `type`, `key` and `count` fields. + """ + + where_clause = ["relates_to_id = ?", "relation_type = ?"] + where_args = [event_id, RelationTypes.ANNOTATION] + + if event_type: + where_clause.append("type = ?") + where_args.append(event_type) + + having_clause = generate_pagination_where_clause( + direction=direction, + column_names=("COUNT(*)", "MAX(stream_ordering)"), + from_token=attr.astuple(from_token) if from_token else None, + to_token=attr.astuple(to_token) if to_token else None, + engine=self.database_engine, + ) + + if direction == "b": + order = "DESC" + else: + order = "ASC" + + if having_clause: + having_clause = "HAVING " + having_clause + else: + having_clause = "" + + sql = """ + SELECT type, aggregation_key, COUNT(*), MAX(stream_ordering) + FROM event_relations + INNER JOIN events USING (event_id) + WHERE {where_clause} + GROUP BY relation_type, type, aggregation_key + {having_clause} + ORDER BY COUNT(*) {order}, MAX(stream_ordering) {order} + LIMIT ? + """.format( + where_clause=" AND ".join(where_clause), + order=order, + having_clause=having_clause, + ) + + def _get_aggregation_groups_for_event_txn(txn): + txn.execute(sql, where_args + [limit + 1]) + + next_batch = None + events = [] + for row in txn: + events.append({"type": row[0], "key": row[1], "count": row[2]}) + next_batch = AggregationPaginationToken(row[2], row[3]) + + if len(events) <= limit: + next_batch = None + + return PaginationChunk( + chunk=list(events[:limit]), next_batch=next_batch, prev_batch=from_token + ) + + return self.runInteraction( + "get_aggregation_groups_for_event", _get_aggregation_groups_for_event_txn + ) + + @cachedInlineCallbacks() + def get_applicable_edit(self, event_id): + """Get the most recent edit (if any) that has happened for the given + event. + + Correctly handles checking whether edits were allowed to happen. + + Args: + event_id (str): The original event ID + + Returns: + Deferred[EventBase|None]: Returns the most recent edit, if any. + """ + + # We only allow edits for `m.room.message` events that have the same sender + # and event type. We can't assert these things during regular event auth so + # we have to do the checks post hoc. + + # Fetches latest edit that has the same type and sender as the + # original, and is an `m.room.message`. + sql = """ + SELECT edit.event_id FROM events AS edit + INNER JOIN event_relations USING (event_id) + INNER JOIN events AS original ON + original.event_id = relates_to_id + AND edit.type = original.type + AND edit.sender = original.sender + WHERE + relates_to_id = ? + AND relation_type = ? + AND edit.type = 'm.room.message' + ORDER by edit.origin_server_ts DESC, edit.event_id DESC + LIMIT 1 + """ + + def _get_applicable_edit_txn(txn): + txn.execute( + sql, (event_id, RelationTypes.REPLACES,) + ) + row = txn.fetchone() + if row: + return row[0] + + edit_id = yield self.runInteraction( + "get_applicable_edit", _get_applicable_edit_txn + ) + + if not edit_id: + return + + edit_event = yield self.get_event(edit_id, allow_none=True) + defer.returnValue(edit_event) + + +class RelationsStore(RelationsWorkerStore): + def _handle_event_relations(self, txn, event): + """Handles inserting relation data during peristence of events + + Args: + txn + event (EventBase) + """ + relation = event.content.get("m.relates_to") + if not relation: + # No relations + return + + rel_type = relation.get("rel_type") + if rel_type not in ( + RelationTypes.ANNOTATION, + RelationTypes.REFERENCES, + RelationTypes.REPLACES, + ): + # Unknown relation type + return + + parent_id = relation.get("event_id") + if not parent_id: + # Invalid relation + return + + aggregation_key = relation.get("key") + + self._simple_insert_txn( + txn, + table="event_relations", + values={ + "event_id": event.event_id, + "relates_to_id": parent_id, + "relation_type": rel_type, + "aggregation_key": aggregation_key, + }, + ) + + txn.call_after(self.get_relations_for_event.invalidate_many, (parent_id,)) + txn.call_after( + self.get_aggregation_groups_for_event.invalidate_many, (parent_id,) + ) + + if rel_type == RelationTypes.REPLACES: + txn.call_after(self.get_applicable_edit.invalidate, (parent_id,)) + + def _handle_redaction(self, txn, redacted_event_id): + """Handles receiving a redaction and checking whether we need to remove + any redacted relations from the database. + + Args: + txn + redacted_event_id (str): The event that was redacted. + """ + + self._simple_delete_txn( + txn, + table="event_relations", + keyvalues={ + "event_id": redacted_event_id, + } + ) |