Rearrange persist_event so that do all the queries that need to be done before returning early if we have already persisted that event.

1 files changed, 74 insertions, 71 deletions

diff --git a/synapse/storage/__init__.py b/synapse/storage/__init__.py
index 93ab26fcd1..30ce378900 100644
--- a/synapse/storage/__init__.py
+++ b/synapse/storage/__init__.py
@@ -163,19 +163,70 @@ class DataStore(RoomMemberStore, RoomStore,
     def _persist_event_txn(self, txn, event, context, backfilled,
                            stream_ordering=None, is_new_state=True,
                            current_state=None):
-        if event.type == EventTypes.Member:
-            self._store_room_member_txn(txn, event)
-        elif event.type == EventTypes.Feedback:
-            self._store_feedback_txn(txn, event)
-        elif event.type == EventTypes.Name:
-            self._store_room_name_txn(txn, event)
-        elif event.type == EventTypes.Topic:
-            self._store_room_topic_txn(txn, event)
-        elif event.type == EventTypes.Redaction:
-            self._store_redaction(txn, event)
+
+        # We purposefully do this first since if we include a `current_state`
+        # key, we *want* to update the `current_state_events` table
+        if current_state:
+            txn.execute(
+                "DELETE FROM current_state_events WHERE room_id = ?",
+                (event.room_id,)
+            )
+
+            for s in current_state:
+                self._simple_insert_txn(
+                    txn,
+                    "current_state_events",
+                    {
+                        "event_id": s.event_id,
+                        "room_id": s.room_id,
+                        "type": s.type,
+                        "state_key": s.state_key,
+                    },
+                    or_replace=True,
+                )
+
+        if event.is_state() and is_new_state:
+            if not backfilled and not context.rejected:
+                self._simple_insert_txn(
+                    txn,
+                    table="state_forward_extremities",
+                    values={
+                        "event_id": event.event_id,
+                        "room_id": event.room_id,
+                        "type": event.type,
+                        "state_key": event.state_key,
+                    },
+                    or_replace=True,
+                )
+
+                for prev_state_id, _ in event.prev_state:
+                    self._simple_delete_txn(
+                        txn,
+                        table="state_forward_extremities",
+                        keyvalues={
+                            "event_id": prev_state_id,
+                        }
+                    )
 
         outlier = event.internal_metadata.is_outlier()
 
+        if not outlier:
+            self._store_state_groups_txn(txn, event, context)
+
+            self._update_min_depth_for_room_txn(
+                txn,
+                event.room_id,
+                event.depth
+            )
+
+        self._handle_prev_events(
+            txn,
+            outlier=outlier,
+            event_id=event.event_id,
+            prev_events=event.prev_events,
+            room_id=event.room_id,
+        )
+
         have_persisted = self._simple_select_one_onecol_txn(
             txn,
             table="event_json",
@@ -209,6 +260,17 @@ class DataStore(RoomMemberStore, RoomStore,
                 )
             return
 
+        if event.type == EventTypes.Member:
+            self._store_room_member_txn(txn, event)
+        elif event.type == EventTypes.Feedback:
+            self._store_feedback_txn(txn, event)
+        elif event.type == EventTypes.Name:
+            self._store_room_name_txn(txn, event)
+        elif event.type == EventTypes.Topic:
+            self._store_room_topic_txn(txn, event)
+        elif event.type == EventTypes.Redaction:
+            self._store_redaction(txn, event)
+
         event_dict = {
             k: v
             for k, v in event.get_dict().items()
@@ -273,41 +335,10 @@ class DataStore(RoomMemberStore, RoomStore,
             )
             raise _RollbackButIsFineException("_persist_event")
 
-        self._handle_prev_events(
-            txn,
-            outlier=outlier,
-            event_id=event.event_id,
-            prev_events=event.prev_events,
-            room_id=event.room_id,
-        )
-
-        if not outlier:
-            self._store_state_groups_txn(txn, event, context)
-
         if context.rejected:
             self._store_rejections_txn(txn, event.event_id, context.rejected)
 
-        if current_state:
-            txn.execute(
-                "DELETE FROM current_state_events WHERE room_id = ?",
-                (event.room_id,)
-            )
-
-            for s in current_state:
-                self._simple_insert_txn(
-                    txn,
-                    "current_state_events",
-                    {
-                        "event_id": s.event_id,
-                        "room_id": s.room_id,
-                        "type": s.type,
-                        "state_key": s.state_key,
-                    },
-                    or_replace=True,
-                )
-
-        is_state = hasattr(event, "state_key") and event.state_key is not None
-        if is_state:
+        if event.is_state():
             vals = {
                 "event_id": event.event_id,
                 "room_id": event.room_id,
@@ -315,6 +346,7 @@ class DataStore(RoomMemberStore, RoomStore,
                 "state_key": event.state_key,
             }
 
+            # TODO: How does this work with backfilling?
             if hasattr(event, "replaces_state"):
                 vals["prev_state"] = event.replaces_state
 
@@ -351,28 +383,6 @@ class DataStore(RoomMemberStore, RoomStore,
                     or_ignore=True,
                 )
 
-            if not backfilled and not context.rejected:
-                self._simple_insert_txn(
-                    txn,
-                    table="state_forward_extremities",
-                    values={
-                        "event_id": event.event_id,
-                        "room_id": event.room_id,
-                        "type": event.type,
-                        "state_key": event.state_key,
-                    },
-                    or_replace=True,
-                )
-
-                for prev_state_id, _ in event.prev_state:
-                    self._simple_delete_txn(
-                        txn,
-                        table="state_forward_extremities",
-                        keyvalues={
-                            "event_id": prev_state_id,
-                        }
-                    )
-
         for hash_alg, hash_base64 in event.hashes.items():
             hash_bytes = decode_base64(hash_base64)
             self._store_event_content_hash_txn(
@@ -403,13 +413,6 @@ class DataStore(RoomMemberStore, RoomStore,
             txn, event.event_id, ref_alg, ref_hash_bytes
         )
 
-        if not outlier:
-            self._update_min_depth_for_room_txn(
-                txn,
-                event.room_id,
-                event.depth
-            )
-
     def _store_redaction(self, txn, event):
         txn.execute(
             "INSERT OR IGNORE INTO redactions "