Faster joins: omit partial rooms from eager syncs until the resync completes (#14870)

* Allow `AbstractSet` in `StrCollection`

Or else frozensets are excluded. This will be useful in an upcoming
commit where I plan to change a function that accepts `List[str]` to
accept `StrCollection` instead.

* `rooms_to_exclude` -> `rooms_to_exclude_globally`

I am about to make use of this exclusion mechanism to exclude rooms for
a specific user and a specific sync. This rename helps to clarify the
distinction between the global config and the rooms to exclude for a
specific sync.

* Better function names for internal sync methods

* Track a list of excluded rooms on SyncResultBuilder

I plan to feed a list of partially stated rooms for this sync to ignore

* Exclude partial state rooms during eager sync

using the mechanism established in the previous commit

* Track un-partial-state stream in sync tokens

So that we can work out which rooms have become fully-stated during a
given sync period.

* Fix mutation of `@cached` return value

This was fouling up a complement test added alongside this PR.
Excluding a room would mean the set of forgotten rooms in the cache
would be extended. This means that room could be erroneously considered
forgotten in the future.

Introduced in #12310, Synapse 1.57.0. I don't think this had any
user-visible side effects (until now).

* SyncResultBuilder: track rooms to force as newly joined

Similar plan as before. We've omitted rooms from certain sync responses;
now we establish the mechanism to reintroduce them into future syncs.

* Read new field, to present rooms as newly joined

* Force un-partial-stated rooms to be newly-joined

for eager incremental syncs only, provided they're still fully stated

* Notify user stream listeners to wake up long polling syncs

* Changelog

* Typo fix

Co-authored-by: Sean Quah <8349537+squahtx@users.noreply.github.com>

* Unnecessary list cast

Co-authored-by: Sean Quah <8349537+squahtx@users.noreply.github.com>

* Rephrase comment

Co-authored-by: Sean Quah <8349537+squahtx@users.noreply.github.com>

* Another comment

Co-authored-by: Sean Quah <8349537+squahtx@users.noreply.github.com>

* Fixup merge(?)

* Poke notifier when receiving un-partial-stated msg over replication

* Fixup merge whoops

Thanks MV :)

Co-authored-by: Mathieu Velen <mathieuv@matrix.org>

Co-authored-by: Mathieu Velten <mathieuv@matrix.org>
Co-authored-by: Sean Quah <8349537+squahtx@users.noreply.github.com>

2 files changed, 8 insertions, 6 deletions

diff --git a/tests/rest/client/test_rooms.py b/tests/rest/client/test_rooms.py
index b4daace556..9222cab198 100644
--- a/tests/rest/client/test_rooms.py
+++ b/tests/rest/client/test_rooms.py
@@ -1987,7 +1987,7 @@ class RoomMessageListTestCase(RoomBase):
         self.room_id = self.helper.create_room_as(self.user_id)
 
     def test_topo_token_is_accepted(self) -> None:
-        token = "t1-0_0_0_0_0_0_0_0_0"
+        token = "t1-0_0_0_0_0_0_0_0_0_0"
         channel = self.make_request(
             "GET", "/rooms/%s/messages?access_token=x&from=%s" % (self.room_id, token)
         )
@@ -1998,7 +1998,7 @@ class RoomMessageListTestCase(RoomBase):
         self.assertTrue("end" in channel.json_body)
 
     def test_stream_token_is_accepted_for_fwd_pagianation(self) -> None:
-        token = "s0_0_0_0_0_0_0_0_0"
+        token = "s0_0_0_0_0_0_0_0_0_0"
         channel = self.make_request(
             "GET", "/rooms/%s/messages?access_token=x&from=%s" % (self.room_id, token)
         )
@@ -2728,7 +2728,7 @@ class LabelsTestCase(unittest.HomeserverTestCase):
         """Test that we can filter by a label on a /messages request."""
         self._send_labelled_messages_in_room()
 
-        token = "s0_0_0_0_0_0_0_0_0"
+        token = "s0_0_0_0_0_0_0_0_0_0"
         channel = self.make_request(
             "GET",
             "/rooms/%s/messages?access_token=%s&from=%s&filter=%s"
@@ -2745,7 +2745,7 @@ class LabelsTestCase(unittest.HomeserverTestCase):
         """Test that we can filter by the absence of a label on a /messages request."""
         self._send_labelled_messages_in_room()
 
-        token = "s0_0_0_0_0_0_0_0_0"
+        token = "s0_0_0_0_0_0_0_0_0_0"
         channel = self.make_request(
             "GET",
             "/rooms/%s/messages?access_token=%s&from=%s&filter=%s"
@@ -2768,7 +2768,7 @@ class LabelsTestCase(unittest.HomeserverTestCase):
         """
         self._send_labelled_messages_in_room()
 
-        token = "s0_0_0_0_0_0_0_0_0"
+        token = "s0_0_0_0_0_0_0_0_0_0"
         channel = self.make_request(
             "GET",
             "/rooms/%s/messages?access_token=%s&from=%s&filter=%s"
diff --git a/tests/rest/client/test_sync.py b/tests/rest/client/test_sync.py
index 0af643ecd9..c9afa0f3dd 100644
--- a/tests/rest/client/test_sync.py
+++ b/tests/rest/client/test_sync.py
@@ -913,7 +913,9 @@ class ExcludeRoomTestCase(unittest.HomeserverTestCase):
 
         # We need to manually append the room ID, because we can't know the ID before
         # creating the room, and we can't set the config after starting the homeserver.
-        self.hs.get_sync_handler().rooms_to_exclude.append(self.excluded_room_id)
+        self.hs.get_sync_handler().rooms_to_exclude_globally.append(
+            self.excluded_room_id
+        )
 
     def test_join_leave(self) -> None:
         """Tests that rooms are correctly excluded from the 'join' and 'leave' sections of