SQLALchemy DB Session with Flask, Postgres

Question

I'm using SQLAlchemy with Flask as shown here: http://flask.pocoo.org/docs/patterns/sqlalchemy/

I have a Selenium test suite that first runs with Firefox and then with Chrome.

Before the start of tests on each browsers, tables in the test database (PostgreSQL) are dropped and created.

It runs perfectly for the first browsers, but for the second browser the SQL create / drop attempt just freezes and no errors are shown.

I believe this is because of open SQLAlchemy sessions, is that correct?

Answer 1

I believe this is because of open SQLAlchemy sessions, is that correct?

That's most likely the case. To confirm it, connect to the postgres database and run SELECT * FROM pg_stat_activity;

I'm not sure how you handle the DB creation/dropping but you may want to call dispose() and possibly recreate() on the SQLAlchemy connection pool, after making sure that any checked out connection has been returned (for example, with session.close()).