anonymousland-synapse/synapse/storage/relations.py
2019-05-15 13:36:51 +01:00

143 lines
4.0 KiB
Python

# -*- 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 synapse.api.constants import RelationTypes
from synapse.storage._base import SQLBaseStore
logger = logging.getLogger(__name__)
@attr.s
class PaginationChunk(object):
"""Returned by relation pagination APIs.
Attributes:
chunk (list): The rows returned by pagination
"""
chunk = attr.ib()
def to_dict(self):
d = {"chunk": self.chunk}
return d
class RelationsStore(SQLBaseStore):
def get_relations_for_event(
self, event_id, relation_type=None, event_type=None, limit=5, direction="b"
):
"""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.
limit (int): Only fetch the most recent `limit` events.
direction (str): Whether to fetch the most recent first (`"b"`) or
the oldest first (`"f"`).
Returns:
Deferred[PaginationChunk]: List of event IDs that match relations
requested. The rows are of the form `{"event_id": "..."}`.
"""
# TODO: Pagination tokens
where_clause = ["relates_to_id = ?"]
where_args = [event_id]
if relation_type:
where_clause.append("relation_type = ?")
where_args.append(relation_type)
if event_type:
where_clause.append("type = ?")
where_args.append(event_type)
order = "ASC"
if direction == "b":
order = "DESC"
sql = """
SELECT event_id 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])
events = [{"event_id": row[0]} for row in txn]
return PaginationChunk(
chunk=list(events[:limit]),
)
return self.runInteraction(
"get_recent_references_for_event", _get_recent_references_for_event_txn
)
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,
},
)