Allow paginating backwards from stream token

This commit is contained in:
Erik Johnston 2016-01-28 11:52:34 +00:00
parent ba8931829b
commit 4e7948b47a
3 changed files with 24 additions and 16 deletions

View File

@ -16,7 +16,7 @@
from twisted.internet import defer from twisted.internet import defer
from synapse.api.constants import EventTypes, Membership from synapse.api.constants import EventTypes, Membership
from synapse.api.errors import SynapseError, AuthError, Codes from synapse.api.errors import AuthError, Codes
from synapse.streams.config import PaginationConfig from synapse.streams.config import PaginationConfig
from synapse.events.utils import serialize_event from synapse.events.utils import serialize_event
from synapse.events.validator import EventValidator from synapse.events.validator import EventValidator
@ -119,9 +119,12 @@ class MessageHandler(BaseHandler):
if source_config.direction == 'b': if source_config.direction == 'b':
# if we're going backwards, we might need to backfill. This # if we're going backwards, we might need to backfill. This
# requires that we have a topo token. # requires that we have a topo token.
if room_token.topological is None: if room_token.topological:
raise SynapseError(400, "Invalid token: cannot paginate " max_topo = room_token.topological
"backwards from a stream token") else:
max_topo = yield self.store.get_max_topological_token_for_stream_and_room(
room_id, room_token.stream
)
if membership == Membership.LEAVE: if membership == Membership.LEAVE:
# If they have left the room then clamp the token to be before # If they have left the room then clamp the token to be before
@ -131,11 +134,11 @@ class MessageHandler(BaseHandler):
member_event_id member_event_id
) )
leave_token = RoomStreamToken.parse(leave_token) leave_token = RoomStreamToken.parse(leave_token)
if leave_token.topological < room_token.topological: if leave_token.topological < max_topo:
source_config.from_key = str(leave_token) source_config.from_key = str(leave_token)
yield self.hs.get_handlers().federation_handler.maybe_backfill( yield self.hs.get_handlers().federation_handler.maybe_backfill(
room_id, room_token.topological room_id, max_topo
) )
events, next_key = yield data_source.get_pagination_rows( events, next_key = yield data_source.get_pagination_rows(

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@ -234,10 +234,10 @@ class StreamStore(SQLBaseStore):
get_prev_content=True get_prev_content=True
) )
ret.reverse()
self._set_before_and_after(ret, rows, topo_order=False) self._set_before_and_after(ret, rows, topo_order=False)
ret.reverse()
if rows: if rows:
key = "s%d" % min(r["stream_ordering"] for r in rows) key = "s%d" % min(r["stream_ordering"] for r in rows)
else: else:
@ -570,6 +570,18 @@ class StreamStore(SQLBaseStore):
row["topological_ordering"], row["stream_ordering"],) row["topological_ordering"], row["stream_ordering"],)
) )
def get_max_topological_token_for_stream_and_room(self, room_id, stream_key):
sql = (
"SELECT max(topological_ordering) FROM events"
" WHERE room_id = ? AND stream_ordering < ?"
)
return self._execute(
"get_max_topological_token_for_stream_and_room", None,
sql, room_id, stream_key,
).addCallback(
lambda r: r[0][0] if r else 0
)
def _get_max_topological_txn(self, txn): def _get_max_topological_txn(self, txn):
txn.execute( txn.execute(
"SELECT MAX(topological_ordering) FROM events" "SELECT MAX(topological_ordering) FROM events"

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@ -1044,13 +1044,6 @@ class RoomMessageListTestCase(RestTestCase):
self.assertTrue("chunk" in response) self.assertTrue("chunk" in response)
self.assertTrue("end" in response) self.assertTrue("end" in response)
@defer.inlineCallbacks
def test_stream_token_is_rejected_for_back_pagination(self):
(code, response) = yield self.mock_resource.trigger_get(
"/rooms/%s/messages?access_token=x&from=s0_0_0_0_0&dir=b" %
self.room_id)
self.assertEquals(400, code)
@defer.inlineCallbacks @defer.inlineCallbacks
def test_stream_token_is_accepted_for_fwd_pagianation(self): def test_stream_token_is_accepted_for_fwd_pagianation(self):
token = "s0_0_0_0_0" token = "s0_0_0_0_0"