manager.py

mapper = {
    'function1': function1,
    'function2': function2
}

def execute_pending_tasks():
    all_pending_tasks = Task.query.all()
    for t in all_pending_tasks:
        try:
            associated_function = mapper.get(t.type, False)
            if associated_function:
                kwargs = json.loads(t.arguments)
                associated_function(**kwargs)
                db.session.delete(t)
                db.session.commit()
        except Exception as e:
            # Send Email when failed
            exception_str = traceback.format_exc()
            mail_sender.send('alert@careful.com', 'me@lolo.today',
                             '[FAILURE] Task Scheduler: task %s' % t.type,
                             '<pre>%s</pre>' % exception_str)


@manager.command
def execute_tasks():
    execute_pending_tasks()