diff options
Diffstat (limited to 'synapse/storage/event_federation.py')
| -rw-r--r-- | synapse/storage/event_federation.py | 386 |
1 files changed, 386 insertions, 0 deletions
diff --git a/synapse/storage/event_federation.py b/synapse/storage/event_federation.py new file mode 100644 index 0000000000..6c559f8f63 --- /dev/null +++ b/synapse/storage/event_federation.py @@ -0,0 +1,386 @@ +# -*- coding: utf-8 -*- +# Copyright 2014 OpenMarket 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. + +from ._base import SQLBaseStore +from syutil.base64util import encode_base64 + +import logging + + +logger = logging.getLogger(__name__) + + +class EventFederationStore(SQLBaseStore): + """ Responsible for storing and serving up the various graphs associated + with an event. Including the main event graph and the auth chains for an + event. + + Also has methods for getting the front (latest) and back (oldest) edges + of the event graphs. These are used to generate the parents for new events + and backfilling from another server respectively. + """ + + def get_auth_chain(self, event_id): + return self.runInteraction( + "get_auth_chain", + self._get_auth_chain_txn, + event_id + ) + + def _get_auth_chain_txn(self, txn, event_id): + results = self._get_auth_chain_ids_txn(txn, event_id) + + sql = "SELECT * FROM events WHERE event_id = ?" + rows = [] + for ev_id in results: + c = txn.execute(sql, (ev_id,)) + rows.extend(self.cursor_to_dict(c)) + + return self._parse_events_txn(txn, rows) + + def get_auth_chain_ids(self, event_id): + return self.runInteraction( + "get_auth_chain_ids", + self._get_auth_chain_ids_txn, + event_id + ) + + def _get_auth_chain_ids_txn(self, txn, event_id): + results = set() + + base_sql = ( + "SELECT auth_id FROM event_auth WHERE %s" + ) + + front = set([event_id]) + while front: + sql = base_sql % ( + " OR ".join(["event_id=?"] * len(front)), + ) + + txn.execute(sql, list(front)) + front = [r[0] for r in txn.fetchall()] + results.update(front) + + return list(results) + + def get_oldest_events_in_room(self, room_id): + return self.runInteraction( + "get_oldest_events_in_room", + self._get_oldest_events_in_room_txn, + room_id, + ) + + def _get_oldest_events_in_room_txn(self, txn, room_id): + return self._simple_select_onecol_txn( + txn, + table="event_backward_extremities", + keyvalues={ + "room_id": room_id, + }, + retcol="event_id", + ) + + def get_latest_events_in_room(self, room_id): + return self.runInteraction( + "get_latest_events_in_room", + self._get_latest_events_in_room, + room_id, + ) + + def _get_latest_events_in_room(self, txn, room_id): + sql = ( + "SELECT e.event_id, e.depth FROM events as e " + "INNER JOIN event_forward_extremities as f " + "ON e.event_id = f.event_id " + "WHERE f.room_id = ?" + ) + + txn.execute(sql, (room_id, )) + + results = [] + for event_id, depth in txn.fetchall(): + hashes = self._get_event_reference_hashes_txn(txn, event_id) + prev_hashes = { + k: encode_base64(v) for k, v in hashes.items() + if k == "sha256" + } + results.append((event_id, prev_hashes, depth)) + + return results + + def _get_latest_state_in_room(self, txn, room_id, type, state_key): + event_ids = self._simple_select_onecol_txn( + txn, + table="state_forward_extremities", + keyvalues={ + "room_id": room_id, + "type": type, + "state_key": state_key, + }, + retcol="event_id", + ) + + results = [] + for event_id in event_ids: + hashes = self._get_event_reference_hashes_txn(txn, event_id) + prev_hashes = { + k: encode_base64(v) for k, v in hashes.items() + if k == "sha256" + } + results.append((event_id, prev_hashes)) + + return results + + def _get_prev_events(self, txn, event_id): + results = self._get_prev_events_and_state( + txn, + event_id, + is_state=0, + ) + + return [(e_id, h, ) for e_id, h, _ in results] + + def _get_prev_state(self, txn, event_id): + results = self._get_prev_events_and_state( + txn, + event_id, + is_state=1, + ) + + return [(e_id, h, ) for e_id, h, _ in results] + + def _get_prev_events_and_state(self, txn, event_id, is_state=None): + keyvalues = { + "event_id": event_id, + } + + if is_state is not None: + keyvalues["is_state"] = is_state + + res = self._simple_select_list_txn( + txn, + table="event_edges", + keyvalues=keyvalues, + retcols=["prev_event_id", "is_state"], + ) + + results = [] + for d in res: + hashes = self._get_event_reference_hashes_txn( + txn, + d["prev_event_id"] + ) + prev_hashes = { + k: encode_base64(v) for k, v in hashes.items() + if k == "sha256" + } + results.append((d["prev_event_id"], prev_hashes, d["is_state"])) + + return results + + def _get_auth_events(self, txn, event_id): + auth_ids = self._simple_select_onecol_txn( + txn, + table="event_auth", + keyvalues={ + "event_id": event_id, + }, + retcol="auth_id", + ) + + results = [] + for auth_id in auth_ids: + hashes = self._get_event_reference_hashes_txn(txn, auth_id) + prev_hashes = { + k: encode_base64(v) for k, v in hashes.items() + if k == "sha256" + } + results.append((auth_id, prev_hashes)) + + return results + + def get_min_depth(self, room_id): + """ For hte given room, get the minimum depth we have seen for it. + """ + return self.runInteraction( + "get_min_depth", + self._get_min_depth_interaction, + room_id, + ) + + def _get_min_depth_interaction(self, txn, room_id): + min_depth = self._simple_select_one_onecol_txn( + txn, + table="room_depth", + keyvalues={"room_id": room_id}, + retcol="min_depth", + allow_none=True, + ) + + return int(min_depth) if min_depth is not None else None + + def _update_min_depth_for_room_txn(self, txn, room_id, depth): + min_depth = self._get_min_depth_interaction(txn, room_id) + + do_insert = depth < min_depth if min_depth else True + + if do_insert: + self._simple_insert_txn( + txn, + table="room_depth", + values={ + "room_id": room_id, + "min_depth": depth, + }, + or_replace=True, + ) + + def _handle_prev_events(self, txn, outlier, event_id, prev_events, + room_id): + """ + For the given event, update the event edges table and forward and + backward extremities tables. + """ + for e_id, _ in prev_events: + # TODO (erikj): This could be done as a bulk insert + self._simple_insert_txn( + txn, + table="event_edges", + values={ + "event_id": event_id, + "prev_event_id": e_id, + "room_id": room_id, + "is_state": 0, + }, + or_ignore=True, + ) + + # Update the extremities table if this is not an outlier. + if not outlier: + for e_id, _ in prev_events: + # TODO (erikj): This could be done as a bulk insert + self._simple_delete_txn( + txn, + table="event_forward_extremities", + keyvalues={ + "event_id": e_id, + "room_id": room_id, + } + ) + + # We only insert as a forward extremity the new event if there are + # no other events that reference it as a prev event + query = ( + "INSERT OR IGNORE INTO %(table)s (event_id, room_id) " + "SELECT ?, ? WHERE NOT EXISTS (" + "SELECT 1 FROM %(event_edges)s WHERE " + "prev_event_id = ? " + ")" + ) % { + "table": "event_forward_extremities", + "event_edges": "event_edges", + } + + logger.debug("query: %s", query) + + txn.execute(query, (event_id, room_id, event_id)) + + # Insert all the prev_events as a backwards thing, they'll get + # deleted in a second if they're incorrect anyway. + for e_id, _ in prev_events: + # TODO (erikj): This could be done as a bulk insert + self._simple_insert_txn( + txn, + table="event_backward_extremities", + values={ + "event_id": e_id, + "room_id": room_id, + }, + or_ignore=True, + ) + + # Also delete from the backwards extremities table all ones that + # reference events that we have already seen + query = ( + "DELETE FROM event_backward_extremities WHERE EXISTS (" + "SELECT 1 FROM events " + "WHERE " + "event_backward_extremities.event_id = events.event_id " + "AND not events.outlier " + ")" + ) + txn.execute(query) + + def get_backfill_events(self, room_id, event_list, limit): + """Get a list of Events for a given topic that occurred before (and + including) the events in event_list. Return a list of max size `limit` + + Args: + txn + room_id (str) + event_list (list) + limit (int) + """ + return self.runInteraction( + "get_backfill_events", + self._get_backfill_events, room_id, event_list, limit + ) + + def _get_backfill_events(self, txn, room_id, event_list, limit): + logger.debug( + "_get_backfill_events: %s, %s, %s", + room_id, repr(event_list), limit + ) + + event_results = event_list + + front = event_list + + query = ( + "SELECT prev_event_id FROM event_edges " + "WHERE room_id = ? AND event_id = ? " + "LIMIT ?" + ) + + # We iterate through all event_ids in `front` to select their previous + # events. These are dumped in `new_front`. + # We continue until we reach the limit *or* new_front is empty (i.e., + # we've run out of things to select + while front and len(event_results) < limit: + + new_front = [] + for event_id in front: + logger.debug( + "_backfill_interaction: id=%s", + event_id + ) + + txn.execute( + query, + (room_id, event_id, limit - len(event_results)) + ) + + for row in txn.fetchall(): + logger.debug( + "_backfill_interaction: got id=%s", + *row + ) + new_front.append(row[0]) + + front = new_front + event_results += new_front + + return self._get_events_txn(txn, event_results) |