Fix _get_backfill_events to return events in the correct order

This commit is contained in:
Erik Johnston 2015-05-20 12:57:00 +01:00
parent 20814fabdd
commit 2bc60c55af

View File

@ -17,6 +17,7 @@ from ._base import SQLBaseStore, cached
from syutil.base64util import encode_base64
import logging
from Queue import PriorityQueue
logger = logging.getLogger(__name__)
@ -380,41 +381,41 @@ class EventFederationStore(SQLBaseStore):
event_results = set(event_list)
front = event_list
# We want to make sure that we do a breadth-first, "depth" ordered
# search.
query = (
"SELECT prev_event_id FROM event_edges "
"WHERE room_id = ? AND event_id = ? "
"LIMIT ?"
"SELECT depth, prev_event_id FROM event_edges"
" INNER JOIN events"
" ON prev_event_id = events.event_id"
" AND event_edges.room_id = events.room_id"
" WHERE event_edges.room_id = ? AND event_edges.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:
queue = PriorityQueue()
new_front = []
for event_id in front:
logger.debug(
"_backfill_interaction: id=%s",
event_id
)
for event_id in event_list:
txn.execute(
query,
(room_id, event_id, limit - len(event_results))
)
txn.execute(
query,
(room_id, event_id, limit - len(event_results))
)
for row in txn.fetchall():
queue.put(row)
for row in txn.fetchall():
logger.debug(
"_backfill_interaction: got id=%s",
*row
)
new_front.append(row[0])
while not queue.empty() and len(event_results) < limit:
_, event_id = queue.get_nowait()
front = new_front
event_results += new_front
event_results.add(event_id)
txn.execute(
query,
(room_id, event_id, limit - len(event_results))
)
for row in txn.fetchall():
queue.put(row)
return self._get_events_txn(txn, event_results)