Objects left on transient state

[sponsfreixes]

I'm finding that my objects are left on a transient state, and that attributes have the wrong type. I've review the docs and other issues on the issue tracker, and I can't see what I am doing wrong.

I have a pytest.ini file with:

[pytest]
mocked-sessions = my_project.models.db.session

And a conftest.py:

import pytest

from my_project.api.app import create_app
from my_project.models import db


@pytest.fixture(scope="session")
def app():
    app = create_app("my_config_file.py")
    app.testing = True
    return app


@pytest.fixture(scope="session")
def _db(app):
    return db

If you are curious about create_app, it's a straightforward Flask app factory:

def create_app(config_filename):
    app = Flask(__name__)
    app.config.from_pyfile(config_filename)

    from my_project.models import db

    db.init_app(app)

    from my_project.api.schemas import ma

    ma.init_app(app)

    from my_project.api.resources import api

    api.init_app(app)

    return app

I have this simple test which POSTs a string and a date, used to instantiate and commit a SQLAlchemy model:

@pytest.mark.usefixtures("client_class")
class TestMyRoute:
    def test_create_simple(self, db_session):
        request_payload = {"name": "foo", "my_date": "2022-07-29"}
        resp = self.client.post(LicenseConfigurationCollection.route, json=request_payload)
        assert resp.status_code == HTTPStatus.OK
        assert is_sub_dict(request_payload,resp.json["data"])

The serialization of this response fails. If I set a breakpoint, I see that just before generating the response, after the object has been created, added to the session and commited, this is how the object looks like:

(Pdb) obj
<MyObject (transient 140384149977696)>
(Pdb) obj.my_date
'2022-07-29'
(Pdb) obj.id
(Pdb) obj.created
(Pdb) 

As you can see, the date is on string format, which is not correct as it should be a datetime.date, given that it's declared on the model as my_date = db.Column(db.Date, nullable=True). Also, id and created are not initialized either, as expected of a transient object.

The created object is added to the session and it is committed properly. Proof is that if I remove the db_session fixture, the code works and the record is created on the DB. Using postman I am also able to verify it. Any insight?