factoryboy pytest session management

Question

I am using pytest as framework for testing my application and I want to use pytest factoryboy as well. Thusfar, my conftest.py looks pretty much like the example:

import factory
from sqlalchemy import create_engine
from sqlalchemy.orm import scoped_session, sessionmaker
from model import model

engine = create_engine('sqlite://')
session = scoped_session(sessionmaker(bind=engine))

# Create tables
model.Base.metadata.create_all(engine)

class ExampleFactory(factory.alchemy.SQLAlchemyModelFactory):

    class Meta:
        model = model.ExampleClass
        sqlalchemy_session = session

    label = factory.Sequence(lambda n: u'object_%d' % n)

I have multiple factories like this. The problem is that when I use factories in this manner, the session will not be torn down every unit test. I'm basically using one big session for the lot of unit tests that I have. Not very ideal. Using fixtures I could refresh a session every unit test. Is there a way to do this using factoryboy pytest?

Answer 1

Just tried a solution found here that do the job pretty well without being too complicated or dirty: wrapping each factory into a fixture which is provided with an other function-scoped session fixture.

This could look like this for you:

@pytest.fixture
def session():
    session = <session creation>
    yield session
    session.rollback()
    session.close()

@pytest.fixture
def exemple_factory(session):
    class ExampleFactory(factory.alchemy.SQLAlchemyModelFactory):

        class Meta:
            model = model.ExampleClass
            sqlalchemy_session = session

        label = factory.Sequence(lambda n: u'object_%d' % n)

    return ExampleFactory