OperationalError: MySQL Connection not available

[admin]

I'm using Flask-SQLAlchemy 1.0, Flask 0.10, SQLAlchemy 0.8.2, and Python 2.7.5. I'm connecting to MySQL 5.6 with Oracle's MySQL Connector/Python 1.0.12.

When I restart my web server (either Apache2 or Flask's built-in), I receive the exception

OperationalError: MySQL Connection not available

after MySQL's

wait_timeout

expires (default 8 hours).

I've found people with <a href="http://mofanim.wordpress.com/2013/01/02/sqlalchemy-mysql-has-gone-away/" rel="nofollow">similar problems</a> and explicitly set

SQLALCHEMY_POOL_RECYCLE = 7200

, even though that's <a href="https://github.com/mitsuhiko/flask-sqlalchemy/blob/master/flask_sqlalchemy/__init__.py#L839" rel="nofollow">Flask-SQLAlchemy's default</a>. When I put a breakpoint <a href="https://github.com/mitsuhiko/flask-sqlalchemy/blob/master/flask_sqlalchemy/__init__.py#L826" rel="nofollow">here</a>, I see that the teardown function is successfully calling

session.remove()

after each request. Any ideas?

<strong>Update 7/21/2014:</strong>

Since this question continues to receive attention, I must add that I <em>did</em> try some of the proposals. Two of my attempts looked like the following:

<strong>First:</strong>

@contextmanager
def safe_commit():
    try:
        yield
        db.session.commit()
    except:
        db.session.rollback()
        raise

This allowed me to wrap my commit calls like so:

with safe_commit():
    model = Model(prop=value)
    db.session.add(model)

I am 99% certain that I did not miss any

db.session.commit

calls with this method and I still had problems.

<strong>Second:</strong>

def managed_session():
    def decorator(f):
        @wraps(f)
        def decorated_function(*args, **kwargs):
            try:
                response = f(*args, **kwargs)
                db.session.commit()
                return response
            except:
                db.session.rollback()
                raise
            finally:
                db.session.close()
        return decorated_function
    return decorator

To further ensure I wasn't missing any commit calls, I made a Flask wrapper that enabled code such as (if I remember correctly):

@managed_session()
def hello(self):
    model = Model(prop=value)
    db.session.add(model)

    return render_template(...

Unfortunately, neither method worked. I also recall trying to issue SELECT(1) calls in an attempt to re-establish the connection, but I don't have that code anymore.

To me, the bottom line is MySQL/SQL Alchemy has issues. When I migrated to Postgres, I didn't have to worry about my commits. Everything just worked.