Factor out common code for search insert

we can reuse the same code as is used for event insert, for doing the
background index population.

synapse/storage/search.py

@@ -13,19 +13,25 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
+from collections import namedtuple
+import logging
+import re
+import ujson as json
+
 from twisted.internet import defer
 
 from .background_updates import BackgroundUpdateStore
 from synapse.api.errors import SynapseError
 from synapse.storage.engines import PostgresEngine, Sqlite3Engine
 
-import logging
-import re
-import ujson as json
-
 
 logger = logging.getLogger(__name__)
 
+SearchEntry = namedtuple('SearchEntry', [
+    'key', 'value', 'event_id', 'room_id', 'stream_ordering',
+    'origin_server_ts',
+])
+
 
 class SearchStore(BackgroundUpdateStore):
 
@@ -49,16 +55,17 @@ class SearchStore(BackgroundUpdateStore):
 
     @defer.inlineCallbacks
     def _background_reindex_search(self, progress, batch_size):
+        # we work through the events table from highest stream id to lowest
         target_min_stream_id = progress["target_min_stream_id_inclusive"]
         max_stream_id = progress["max_stream_id_exclusive"]
         rows_inserted = progress.get("rows_inserted", 0)
 
-        INSERT_CLUMP_SIZE = 1000
         TYPES = ["m.room.name", "m.room.message", "m.room.topic"]
 
         def reindex_search_txn(txn):
             sql = (
-                "SELECT stream_ordering, event_id, room_id, type, content FROM events"
+                "SELECT stream_ordering, event_id, room_id, type, content, "
+                " origin_server_ts FROM events"
                 " WHERE ? <= stream_ordering AND stream_ordering < ?"
                 " AND (%s)"
                 " ORDER BY stream_ordering DESC"
@@ -67,6 +74,10 @@ class SearchStore(BackgroundUpdateStore):
 
             txn.execute(sql, (target_min_stream_id, max_stream_id, batch_size))
 
+            # we could stream straight from the results into
+            # store_search_entries_txn with a generator function, but that
+            # would mean having two cursors open on the database at once.
+            # Instead we just build a list of results.
             rows = self.cursor_to_dict(txn)
             if not rows:
                 return 0
@@ -79,6 +90,8 @@ class SearchStore(BackgroundUpdateStore):
                     event_id = row["event_id"]
                     room_id = row["room_id"]
                     etype = row["type"]
+                    stream_ordering = row["stream_ordering"]
+                    origin_server_ts = row["origin_server_ts"]
                     try:
                         content = json.loads(row["content"])
                     except Exception:
@@ -93,6 +106,8 @@ class SearchStore(BackgroundUpdateStore):
                     elif etype == "m.room.name":
                         key = "content.name"
                         value = content["name"]
+                    else:
+                        raise Exception("unexpected event type %s" % etype)
                 except (KeyError, AttributeError):
                     # If the event is missing a necessary field then
                     # skip over it.
@@ -103,25 +118,16 @@ class SearchStore(BackgroundUpdateStore):
                     # then skip over it
                     continue
 
-                event_search_rows.append((event_id, room_id, key, value))
+                event_search_rows.append(SearchEntry(
+                    key=key,
+                    value=value,
+                    event_id=event_id,
+                    room_id=room_id,
+                    stream_ordering=stream_ordering,
+                    origin_server_ts=origin_server_ts,
+                ))
 
-            if isinstance(self.database_engine, PostgresEngine):
+            self.store_search_entries_txn(txn, event_search_rows)
-                sql = (
-                    "INSERT INTO event_search (event_id, room_id, key, vector)"
-                    " VALUES (?,?,?,to_tsvector('english', ?))"
-                )
-            elif isinstance(self.database_engine, Sqlite3Engine):
-                sql = (
-                    "INSERT INTO event_search (event_id, room_id, key, value)"
-                    " VALUES (?,?,?,?)"
-                )
-            else:
-                # This should be unreachable.
-                raise Exception("Unrecognized database engine")
-
-            for index in range(0, len(event_search_rows), INSERT_CLUMP_SIZE):
-                clump = event_search_rows[index:index + INSERT_CLUMP_SIZE]
-                txn.executemany(sql, clump)
 
             progress = {
                 "target_min_stream_id_inclusive": target_min_stream_id,
@@ -251,26 +257,49 @@ class SearchStore(BackgroundUpdateStore):
             key (str):
             value (str):
         """
+        self.store_search_entries_txn(
+            txn,
+            (SearchEntry(
+                key=key,
+                value=value,
+                event_id=event.event_id,
+                room_id=event.room_id,
+                stream_ordering=event.internal_metadata.stream_ordering,
+                origin_server_ts=event.origin_server_ts,
+            ),),
+        )
+
+    def store_search_entries_txn(self, txn, entries):
+        """Add entries to the search table
+
+        Args:
+            txn (cursor):
+            entries (iterable[SearchEntry]):
+                entries to be added to the table
+        """
         if isinstance(self.database_engine, PostgresEngine):
             sql = (
                 "INSERT INTO event_search"
                 " (event_id, room_id, key, vector, stream_ordering, origin_server_ts)"
                 " VALUES (?,?,?,to_tsvector('english', ?),?,?)"
             )
-            txn.execute(
+
-                sql,
+            args = ((
-                (
+                entry.event_id, entry.room_id, entry.key, entry.value,
-                    event.event_id, event.room_id, key, value,
+                entry.stream_ordering, entry.origin_server_ts,
-                    event.internal_metadata.stream_ordering,
+            ) for entry in entries)
-                    event.origin_server_ts,
+
-                )
+            txn.executemany(sql, args)
-            )
         elif isinstance(self.database_engine, Sqlite3Engine):
             sql = (
                 "INSERT INTO event_search (event_id, room_id, key, value)"
                 " VALUES (?,?,?,?)"
             )
-            txn.execute(sql, (event.event_id, event.room_id, key, value,))
+            args = ((
+                entry.event_id, entry.room_id, entry.key, entry.value,
+            ) for entry in entries)
+
+            txn.executemany(sql, args)
         else:
             # This should be unreachable.
             raise Exception("Unrecognized database engine")