Refcator EventContext to accept state during init

synapse/events/snapshot.py

@@ -60,22 +60,22 @@ class EventContext(object):
         "app_service",
     ]
 
-    def __init__(self):
+    def __init__(self, state_group, current_state_ids, prev_state_ids,
+                 prev_group=None, delta_ids=None):
         # The current state including the current event
-        self.current_state_ids = None
+        self.current_state_ids = current_state_ids
         # The current state excluding the current event
-        self.prev_state_ids = None
-        self.state_group = None
-
-        self.rejected = False
+        self.prev_state_ids = prev_state_ids
+        self.state_group = state_group
 
         # A previously persisted state group and a delta between that
         # and this state.
-        self.prev_group = None
-        self.delta_ids = None
+        self.prev_group = prev_group
+        self.delta_ids = delta_ids
 
-        self.prev_state_events = None
+        self.prev_state_events = []
 
+        self.rejected = False
         self.app_service = None
 
     def serialize(self, event):
@@ -123,27 +123,33 @@ def deserialize(store, input):
         Returns:
             EventContext
         """
-        context = EventContext()
-        context.state_group = input["state_group"]
-        context.rejected = input["rejected"]
-        context.prev_group = input["prev_group"]
-        context.delta_ids = _decode_state_dict(input["delta_ids"])
-        context.prev_state_events = input["prev_state_events"]
-
         # We use the state_group and prev_state_id stuff to pull the
         # current_state_ids out of the DB and construct prev_state_ids.
         prev_state_id = input["prev_state_id"]
         event_type = input["event_type"]
         event_state_key = input["event_state_key"]
 
-        context.current_state_ids = yield store.get_state_ids_for_group(
-            context.state_group,
+        state_group = input["state_group"]
+
+        current_state_ids = yield store.get_state_ids_for_group(
+            state_group,
         )
         if prev_state_id and event_state_key:
-            context.prev_state_ids = dict(context.current_state_ids)
-            context.prev_state_ids[(event_type, event_state_key)] = prev_state_id
+            prev_state_ids = dict(current_state_ids)
+            prev_state_ids[(event_type, event_state_key)] = prev_state_id
         else:
-            context.prev_state_ids = context.current_state_ids
+            prev_state_ids = current_state_ids
+
+        context = EventContext(
+            state_group=state_group,
+            current_state_ids=current_state_ids,
+            prev_state_ids=prev_state_ids,
+            prev_group=input["prev_group"],
+            delta_ids=_decode_state_dict(input["delta_ids"]),
+        )
+
+        context.rejected = input["rejected"]
+        context.prev_state_events = input["prev_state_events"]
 
         app_service_id = input["app_service_id"]
         if app_service_id:

synapse/state.py

@@ -203,25 +203,27 @@ def compute_event_context(self, event, old_state=None):
             # If this is an outlier, then we know it shouldn't have any current
             # state. Certainly store.get_current_state won't return any, and
             # persisting the event won't store the state group.
-            context = EventContext()
             if old_state:
-                context.prev_state_ids = {
+                prev_state_ids = {
                     (s.type, s.state_key): s.event_id for s in old_state
                 }
                 if event.is_state():
-                    context.current_state_ids = dict(context.prev_state_ids)
+                    current_state_ids = dict(prev_state_ids)
                     key = (event.type, event.state_key)
-                    context.current_state_ids[key] = event.event_id
+                    current_state_ids[key] = event.event_id
                 else:
-                    context.current_state_ids = context.prev_state_ids
+                    current_state_ids = prev_state_ids
             else:
-                context.current_state_ids = {}
-                context.prev_state_ids = {}
-            context.prev_state_events = []
+                current_state_ids = {}
+                prev_state_ids = {}
 
             # We don't store state for outliers, so we don't generate a state
-            # froup for it.
-            context.state_group = None
+            # group for it.
+            context = EventContext(
+                state_group=None,
+                current_state_ids=current_state_ids,
+                prev_state_ids=prev_state_ids,
+            )
 
             defer.returnValue(context)
 
@@ -230,93 +232,104 @@ def compute_event_context(self, event, old_state=None):
             # Let's just correctly fill out the context and create a
             # new state group for it.
 
-            context = EventContext()
-            context.prev_state_ids = {
+            prev_state_ids = {
                 (s.type, s.state_key): s.event_id for s in old_state
             }
 
             if event.is_state():
                 key = (event.type, event.state_key)
-                if key in context.prev_state_ids:
-                    replaces = context.prev_state_ids[key]
+                if key in prev_state_ids:
+                    replaces = prev_state_ids[key]
                     if replaces != event.event_id:  # Paranoia check
                         event.unsigned["replaces_state"] = replaces
-                context.current_state_ids = dict(context.prev_state_ids)
-                context.current_state_ids[key] = event.event_id
+                current_state_ids = dict(prev_state_ids)
+                current_state_ids[key] = event.event_id
             else:
-                context.current_state_ids = context.prev_state_ids
+                current_state_ids = prev_state_ids
 
-            context.state_group = yield self.store.store_state_group(
+            state_group = yield self.store.store_state_group(
                 event.event_id,
                 event.room_id,
                 prev_group=None,
                 delta_ids=None,
-                current_state_ids=context.current_state_ids,
+                current_state_ids=current_state_ids,
+            )
+
+            context = EventContext(
+                state_group=state_group,
+                current_state_ids=current_state_ids,
+                prev_state_ids=prev_state_ids,
             )
 
-            context.prev_state_events = []
             defer.returnValue(context)
 
         logger.debug("calling resolve_state_groups from compute_event_context")
         entry = yield self.resolve_state_groups_for_events(
             event.room_id, [e for e, _ in event.prev_events],
         )
 
-        curr_state = entry.state
+        prev_state_ids = entry.state
+        prev_group = None
+        delta_ids = None
 
-        context = EventContext()
-        context.prev_state_ids = curr_state
         if event.is_state():
             # If this is a state event then we need to create a new state
             # group for the state after this event.
 
             key = (event.type, event.state_key)
-            if key in context.prev_state_ids:
-                replaces = context.prev_state_ids[key]
+            if key in prev_state_ids:
+                replaces = prev_state_ids[key]
                 event.unsigned["replaces_state"] = replaces
 
-            context.current_state_ids = dict(context.prev_state_ids)
-            context.current_state_ids[key] = event.event_id
+            current_state_ids = dict(prev_state_ids)
+            current_state_ids[key] = event.event_id
 
             if entry.state_group:
                 # If the state at the event has a state group assigned then
                 # we can use that as the prev group
-                context.prev_group = entry.state_group
-                context.delta_ids = {
+                prev_group = entry.state_group
+                delta_ids = {
                     key: event.event_id
                 }
             elif entry.prev_group:
                 # If the state at the event only has a prev group, then we can
                 # use that as a prev group too.
-                context.prev_group = entry.prev_group
-                context.delta_ids = dict(entry.delta_ids)
-                context.delta_ids[key] = event.event_id
+                prev_group = entry.prev_group
+                delta_ids = dict(entry.delta_ids)
+                delta_ids[key] = event.event_id
 
-            context.state_group = yield self.store.store_state_group(
+            state_group = yield self.store.store_state_group(
                 event.event_id,
                 event.room_id,
-                prev_group=context.prev_group,
-                delta_ids=context.delta_ids,
-                current_state_ids=context.current_state_ids,
+                prev_group=prev_group,
+                delta_ids=delta_ids,
+                current_state_ids=current_state_ids,
             )
         else:
-            context.current_state_ids = context.prev_state_ids
-            context.prev_group = entry.prev_group
-            context.delta_ids = entry.delta_ids
+            current_state_ids = prev_state_ids
+            prev_group = entry.prev_group
+            delta_ids = entry.delta_ids
 
             if entry.state_group is None:
                 entry.state_group = yield self.store.store_state_group(
                     event.event_id,
                     event.room_id,
                     prev_group=entry.prev_group,
                     delta_ids=entry.delta_ids,
-                    current_state_ids=context.current_state_ids,
+                    current_state_ids=current_state_ids,
                 )
                 entry.state_id = entry.state_group
 
-            context.state_group = entry.state_group
+            state_group = entry.state_group
+
+        context = EventContext(
+            state_group=state_group,
+            current_state_ids=current_state_ids,
+            prev_state_ids=prev_state_ids,
+            prev_group=prev_group,
+            delta_ids=delta_ids,
+        )
 
-        context.prev_state_events = []
         defer.returnValue(context)
 
     @defer.inlineCallbacks