From b2f22829475ccfe19e994aedddb8d04995018bf4 Mon Sep 17 00:00:00 2001
From: Matthew Hodgson <matthew@matrix.org>
Date: Mon, 19 Mar 2018 01:15:13 +0000
Subject: [PATCH] make lazy_load_members configurable in filters

---
 synapse/api/filtering.py |  6 ++++++
 synapse/handlers/sync.py | 18 +++++++++---------
 2 files changed, 15 insertions(+), 9 deletions(-)

diff --git a/synapse/api/filtering.py b/synapse/api/filtering.py
index 83206348e5..339e4a31d6 100644
--- a/synapse/api/filtering.py
+++ b/synapse/api/filtering.py
@@ -260,6 +260,9 @@ class FilterCollection(object):
     def ephemeral_limit(self):
         return self._room_ephemeral_filter.limit()
 
+    def lazy_load_members(self):
+        return self._room_state_filter.lazy_load_members()
+
     def filter_presence(self, events):
         return self._presence_filter.filter(events)
 
@@ -416,6 +419,9 @@ class Filter(object):
     def limit(self):
         return self.filter_json.get("limit", 10)
 
+    def lazy_load_members(self):
+        return self.filter_json.get("lazy_load_members", False)
+
 
 def _matches_wildcard(actual_value, filter_value):
     if filter_value.endswith("*"):
diff --git a/synapse/handlers/sync.py b/synapse/handlers/sync.py
index 76f5057377..f521d22e91 100644
--- a/synapse/handlers/sync.py
+++ b/synapse/handlers/sync.py
@@ -442,7 +442,7 @@ class SyncHandler(object):
 
     @defer.inlineCallbacks
     def compute_state_delta(self, room_id, batch, sync_config, since_token, now_token,
-                            full_state, filter_members):
+                            full_state):
         """ Works out the differnce in state between the start of the timeline
         and the previous sync.
 
@@ -455,7 +455,7 @@ class SyncHandler(object):
                 be None.
             now_token(str): Token of the end of the current batch.
             full_state(bool): Whether to force returning the full state.
-            filter_members(bool): Whether to only return state for members
+            lazy_load_members(bool): Whether to only return state for members
                 referenced in this timeline segment
 
         Returns:
@@ -470,8 +470,9 @@ class SyncHandler(object):
 
             types = None
             member_state_ids = {}
+            lazy_load_members = sync_config.filter_collection.lazy_load_members()
 
-            if filter_members:
+            if lazy_load_members:
                 # We only request state for the members needed to display the
                 # timeline:
 
@@ -490,7 +491,7 @@ class SyncHandler(object):
                 if not types:
                     # an optimisation to stop needlessly trying to calculate
                     # member_state_ids
-                    filter_members = False
+                    lazy_load_members = False
 
                 types.append((None, None))  # don't just filter to room members
 
@@ -511,7 +512,7 @@ class SyncHandler(object):
 
                     state_ids = current_state_ids
 
-                if filter_members:
+                if lazy_load_members:
                     member_state_ids = {
                         t: state_ids[t]
                         for t in state_ids if t[0] == EventTypes.Member
@@ -542,7 +543,7 @@ class SyncHandler(object):
                     batch.events[0].event_id, types=types
                 )
 
-                if filter_members:
+                if lazy_load_members:
                     member_state_ids = {
                         t: state_at_timeline_start[t]
                         for t in state_at_timeline_start if t[0] == EventTypes.Member
@@ -562,7 +563,7 @@ class SyncHandler(object):
                 )
             else:
                 state_ids = {}
-                if filter_members:
+                if lazy_load_members:
                     # TODO: filter out redundant members based on their mxids (not their
                     # event_ids) at this point. We know we can do it based on mxid as this
                     # is an non-gappy incremental sync.
@@ -1380,8 +1381,7 @@ class SyncHandler(object):
             return
 
         state = yield self.compute_state_delta(
-            room_id, batch, sync_config, since_token, now_token,
-            full_state=full_state, filter_members=True
+            room_id, batch, sync_config, since_token, now_token, full_state=full_state
         )
 
         if room_builder.rtype == "joined":