Prevent idle transactions

irrd/server/whois/server.py

@@ -131,7 +131,7 @@ def run(self, keep_running=True) -> None:
 
         try:
             self.preloader = Preloader()
-            self.database_handler = DatabaseHandler()
+            self.database_handler = DatabaseHandler(readonly=True)
         except Exception as e:
             logger.error(f'Whois worker failed to initialise preloader or database,'
                          f'unable to start, traceback follows: {e}', exc_info=e)

irrd/storage/database_handler.py

@@ -41,15 +41,21 @@ class DatabaseHandler:
     # The ROA insert buffer is a list of dicts with columm names and their values.
     _roa_insert_buffer: List[Dict[str, Union[str, int]]]
 
-    def __init__(self):
+    def __init__(self, readonly=False):
         """
         Create a new database handler.
 
+        If readonly is True, this instance will expect read queries only.
+        No transaction will be started, all queries will use autocommit.
         """
-        self.journaling_enabled = True
+        self.readonly = readonly
+        self.journaling_enabled = not readonly
         self._connection = get_engine().connect()
-        self._start_transaction()
-        self.preloader = Preloader(enable_queries=False)
+        if self.readonly:
+            self._connection.execution_options(isolation_level="AUTOCOMMIT")
+        else:
+            self._start_transaction()
+            self.preloader = Preloader(enable_queries=False)
 
     def refresh_connection(self) -> None:
         """
@@ -58,15 +64,19 @@ def refresh_connection(self) -> None:
         SQL server has restarted.
         """
         try:
-            self.rollback(start_transaction=False)
+            if not self.readonly:
+                self.rollback(start_transaction=False)
         except Exception:  # pragma: no cover
             pass
         try:
             self.close()
         except Exception:  # pragma: no cover
             pass
         self._connection = get_engine().connect()
-        self._start_transaction()
+        if self.readonly:
+            self._connection.execution_options(isolation_level="AUTOCOMMIT")
+        else:
+            self._start_transaction()
 
     def _start_transaction(self) -> None:
         """Start a fresh transaction."""
@@ -115,7 +125,8 @@ def rollback(self, start_transaction=True) -> None:
     def execute_query(self, query: Union[BaseRPSLObjectDatabaseQuery, DatabaseStatusQuery, RPSLDatabaseObjectStatisticsQuery, ROADatabaseObjectQuery]) -> Iterator[Dict[str, Any]]:
         """Execute an RPSLDatabaseQuery within the current transaction."""
         # To be able to query objects that were just created, flush the buffer.
-        self._flush_rpsl_object_writing_buffer()
+        if not self.readonly:
+            self._flush_rpsl_object_writing_buffer()
         statement = query.finalise_statement()
         result = self._connection.execute(statement)
         for row in result.fetchall():

irrd/storage/preload.py

@@ -333,7 +333,7 @@ def update(self, mock_database_handler=None) -> None:
 
         if not mock_database_handler:  # pragma: no cover
             from .database_handler import DatabaseHandler
-            dh = DatabaseHandler()
+            dh = DatabaseHandler(readonly=True)
         else:
             dh = mock_database_handler
 

irrd/storage/tests/test_database.py

@@ -164,6 +164,8 @@ def test_object_writing_and_status_checking(self, monkeypatch, irrd_database):
         assert len(self.dh._rpsl_upsert_buffer) == 1
         self.dh.upsert_rpsl_object(rpsl_obj_ignored, JournalEntryOrigin.auth_change)
         assert len(self.dh._rpsl_upsert_buffer) == 1
+        # Flush the buffer to make sure the INSERT is issued but then rolled back
+        self.dh._flush_rpsl_object_writing_buffer()
         self.dh.rollback()
 
         statistics = list(self.dh.execute_query(RPSLDatabaseObjectStatisticsQuery()))
@@ -637,6 +639,10 @@ def test_more_less_specific_filters(self, irrd_database, database_handler_with_r
         self.dh.upsert_rpsl_object(rpsl_route_more_specific_26, JournalEntryOrigin.auth_change)
         self.dh.commit()
 
+        self.dh.close()
+        self.dh = DatabaseHandler(readonly=True)
+        self.dh.refresh_connection()
+
         q = RPSLDatabaseQuery().ip_more_specific(IP('192.0.2.0/24'))
         rpsl_pks = [r['rpsl_pk'] for r in self.dh.execute_query(q)]
         assert len(rpsl_pks) == 3, f'Failed query: {q}'