diff --git a/synapse/visibility.py b/synapse/visibility.py
index aef4953c1d..65d79cf0d0 100644
--- a/synapse/visibility.py
+++ b/synapse/visibility.py
@@ -12,15 +12,17 @@
# 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 itertools
import logging
+import operator
from twisted.internet import defer
-from synapse.api.constants import Membership, EventTypes
-
-from synapse.util.logcontext import make_deferred_yieldable, preserve_fn
-
+from synapse.api.constants import EventTypes, Membership
+from synapse.events.utils import prune_event
+from synapse.util.logcontext import (
+ make_deferred_yieldable, preserve_fn,
+)
logger = logging.getLogger(__name__)
@@ -95,16 +97,27 @@ def filter_events_for_client(store, user_id, events, is_peeking=False,
if ignore_dict_content else []
)
+ erased_senders = yield store.are_users_erased((e.sender for e in events))
+
def allowed(event):
"""
Args:
event (synapse.events.EventBase): event to check
+
+ Returns:
+ None|EventBase:
+ None if the user cannot see this event at all
+
+ a redacted copy of the event if they can only see a redacted
+ version
+
+ the original event if they can see it as normal.
"""
if not event.is_state() and event.sender in ignore_list:
- return False
+ return None
if event.event_id in always_include_ids:
- return True
+ return event
state = event_id_to_state[event.event_id]
@@ -118,10 +131,6 @@ def filter_events_for_client(store, user_id, events, is_peeking=False,
if visibility not in VISIBILITY_PRIORITY:
visibility = "shared"
- # if it was world_readable, it's easy: everyone can read it
- if visibility == "world_readable":
- return True
-
# Always allow history visibility events on boundaries. This is done
# by setting the effective visibility to the least restrictive
# of the old vs new.
@@ -155,7 +164,7 @@ def filter_events_for_client(store, user_id, events, is_peeking=False,
if membership == "leave" and (
prev_membership == "join" or prev_membership == "invite"
):
- return True
+ return event
new_priority = MEMBERSHIP_PRIORITY.index(membership)
old_priority = MEMBERSHIP_PRIORITY.index(prev_membership)
@@ -166,31 +175,55 @@ def filter_events_for_client(store, user_id, events, is_peeking=False,
if membership is None:
membership_event = state.get((EventTypes.Member, user_id), None)
if membership_event:
+ # XXX why do we do this?
+ # https://github.com/matrix-org/synapse/issues/3350
if membership_event.event_id not in event_id_forgotten:
membership = membership_event.membership
# if the user was a member of the room at the time of the event,
# they can see it.
if membership == Membership.JOIN:
- return True
+ return event
+
+ # otherwise, it depends on the room visibility.
if visibility == "joined":
# we weren't a member at the time of the event, so we can't
# see this event.
- return False
+ return None
elif visibility == "invited":
# user can also see the event if they were *invited* at the time
# of the event.
- return membership == Membership.INVITE
-
- else:
- # visibility is shared: user can also see the event if they have
- # become a member since the event
+ return (
+ event if membership == Membership.INVITE else None
+ )
+
+ elif visibility == "shared" and is_peeking:
+ # if the visibility is shared, users cannot see the event unless
+ # they have *subequently* joined the room (or were members at the
+ # time, of course)
#
# XXX: if the user has subsequently joined and then left again,
# ideally we would share history up to the point they left. But
- # we don't know when they left.
- return not is_peeking
+ # we don't know when they left. We just treat it as though they
+ # never joined, and restrict access.
+ return None
+
+ # the visibility is either shared or world_readable, and the user was
+ # not a member at the time. We allow it, provided the original sender
+ # has not requested their data to be erased, in which case, we return
+ # a redacted version.
+ if erased_senders[event.sender]:
+ return prune_event(event)
+
+ return event
+
+ # check each event: gives an iterable[None|EventBase]
+ filtered_events = itertools.imap(allowed, events)
+
+ # remove the None entries
+ filtered_events = filter(operator.truth, filtered_events)
- defer.returnValue(list(filter(allowed, events)))
+ # we turn it into a list before returning it.
+ defer.returnValue(list(filtered_events))
|
