flack.py 文件源码

def before_first_request():
    """Start a background thread that looks for users that leave."""
    def find_offline_users(app):
        with app.app_context():
            while True:
                users = User.find_offline_users()
                for user in users:
                    push_model(user)
                db.session.remove()
                time.sleep(5)

    if not current_app.config['TESTING']:
        thread = threading.Thread(target=find_offline_users,
                                  args=(current_app._get_current_object(),))
        thread.start()