How to use Factory Boy with SQLAlchemy session (Lazy Loaded) correctly?

Question

I just run into a problem with my testsuite. I am using a setup with nosetests, SQLAlchemy, Flask and Factory-Boy

I have the following code:

def _create_fixtures(self):
    self.user = UserFactory()
    pprint(db.query(User).all())
    db.add(self.user)
    pprint(db.query(User).all())

witch returns following:

[<User #1>, <User #2>]
[<User #1>, <User #2>]

My UserFactory looks like this:

class UserFactory(Factory):
    FACTORY_FOR = User
    FACTORY_SESSION = db
    email = Sequence(lambda n: 'user{0}@wohnortfinder.com'.format(n))
    password = "password"
    username = Sequence(lambda n: 'user{0}'.format(n))

(yes I am using the normal Factory and not he SQLAlchemy factory, cause this didn't work either)

Why isn't my Factory Object stored to db? It doesn't raise an error, it just doesn't save. I mean even when the current transaction is not committed yet, the query later should queries the actual transaction, shouldn't it?

Oddly when I manually commit the session, it raises an error.

InvalidRequestError: No transaction is begun.

Even though I began a transaction when creating the session object.

def init_engine(uri, **kwargs):
    global engine
    engine = create_engine(uri, **kwargs)
    Base.metadata.create_all(engine)
    db.begin()
    return engine


engine = None

db = scoped_session(lambda: create_session(bind=engine))

any idea why this is not working?

Thanks for your thoughts

Answer 1

您可以在不设置 SQLAlchemy 会话的情况下定义 factory_boy 工厂，然后通过分配给_meta工厂类的属性在初始化 Flask 应用程序和使用工厂之间进行设置：

db_session = set_up_a_db_session_somehow()
MyFactoryClass._meta.sqlalchemy_session = db_session

这似乎适用于范围会话。