Closing a connection tries to close already closed cursors #497
Description
When closing a connection the library will call .close() on every cursor created for that connection, including closed ones. While the code works, it produces a lot of logs of error level, polluting the logs.
Environment details
- OS type and version: Mac OS 10.15.7
- Python version: Python 3.8.2
- pip version: pip 20.3.3
google-cloud-bigqueryversion: 2.7.0
Steps to reproduce
- Close a cursor
- Close the connection
- Error log shows
Exception closing connection <google.cloud.bigquery.dbapi.connection.Connection object at 0x...>
Code example
from contextlib import closing # using pybigquery with closing(engine.raw_connection()) as conn: with closing(conn.cursor()) as cursor: cursor.execute(sql)Stack trace
Traceback (most recent call last): File "/usr/local/lib/python3.7/site-packages/sqlalchemy/pool/base.py", line 270, in _close_connection self._dialect.do_close(connection) File "/usr/local/lib/python3.7/site-packages/sqlalchemy/engine/default.py", line 549, in do_close dbapi_connection.close() File "/usr/local/lib/python3.7/site-packages/google/cloud/bigquery/dbapi/_helpers.py", line 258, in with_closed_check return method(self, *args, **kwargs) File "/usr/local/lib/python3.7/site-packages/google/cloud/bigquery/dbapi/connection.py", line 79, in close cursor_.close() File "/usr/local/lib/python3.7/site-packages/google/cloud/bigquery/dbapi/_helpers.py", line 257, in with_closed_check raise exc_class(exc_msg) google.cloud.bigquery.dbapi.exceptions.ProgrammingError: Operating on a closed cursor. Suggested fix
# google/cloud/bigquery/dbapi/connection.py class Connection(object): ... def close(self): ... for cursor_ in self._cursors_created: if not cursor_._closed: cursor_.close()