Handle non-strings in the event_search table in synapse_port_db

changelog.d/12037.bugfix

@@ -0,0 +1 @@
+Fix a long-standing bug where integers could get into the `event_search` table when using sqlite and prevent migration to PostgreSQL.

scripts/synapse_port_db

@@ -473,7 +473,9 @@ class Porter(object):
                     rows_dict = []
                     for row in rows:
                         d = dict(zip(headers, row))
-                        if "\0" in d["value"]:
+                        if not isinstance(d["value"], str) or "\0" in d["value"]:
+                            # `value` must be a string and contain no null characters.
+                            # Previous versions of Synapse allowed integers to slip into the column.
                             logger.warning("dropping search row %s", d)
                         else:
                             rows_dict.append(d)

synapse/storage/databases/main/events.py

@@ -1954,19 +1954,19 @@ def _handle_redaction(self, txn, redacted_event_id):
         )
 
     def _store_room_topic_txn(self, txn, event):
-        if hasattr(event, "content") and "topic" in event.content:
+        if hasattr(event, "content") and isinstance(event.content.get("topic"), str):
             self.store_event_search_txn(
                 txn, event, "content.topic", event.content["topic"]
             )
 
     def _store_room_name_txn(self, txn, event):
-        if hasattr(event, "content") and "name" in event.content:
+        if hasattr(event, "content") and isinstance(event.content.get("name"), str):
             self.store_event_search_txn(
                 txn, event, "content.name", event.content["name"]
             )
 
     def _store_room_message_txn(self, txn, event):
-        if hasattr(event, "content") and "body" in event.content:
+        if hasattr(event, "content") and isinstance(event.content.get("body"), str):
             self.store_event_search_txn(
                 txn, event, "content.body", event.content["body"]
             )