Don't support limitless pagination

The pagination storage function supported not specifiying a limit on the
number of events returned. This was triggered when using the search or
context API with a limit of zero, which the storage function took to
mean not being limited.
This commit is contained in:
Erik Johnston 2018-05-22 18:15:21 +01:00
parent ad2823ee27
commit 5494c1d71e

View File

@ -684,8 +684,7 @@ class StreamWorkerStore(EventsWorkerStore, SQLBaseStore):
results to only those before
direction(char): Either 'b' or 'f' to indicate whether we are
paginating forwards or backwards from `from_key`.
limit (int): The maximum number of events to return. Zero or less
means no limit.
limit (int): The maximum number of events to return.
event_filter (Filter|None): If provided filters the events to
those that match the filter.
@ -694,6 +693,9 @@ class StreamWorkerStore(EventsWorkerStore, SQLBaseStore):
as a list of _EventDictReturn and a token that points to the end
of the result set.
"""
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.
@ -723,18 +725,14 @@ class StreamWorkerStore(EventsWorkerStore, SQLBaseStore):
bounds += " AND " + filter_clause
args.extend(filter_args)
if int(limit) > 0:
args.append(int(limit))
limit_str = " LIMIT ?"
else:
limit_str = ""
args.append(int(limit))
sql = (
"SELECT event_id, topological_ordering, stream_ordering"
" FROM events"
" WHERE outlier = ? AND room_id = ? AND %(bounds)s"
" ORDER BY topological_ordering %(order)s,"
" stream_ordering %(order)s %(limit)s"
" stream_ordering %(order)s LIMIT ?"
) % {
"bounds": bounds,
"order": order,