[Flask] Flask-sqlalchemy and testing

[Gabor Szabo]

I've solved most of the issues in the second example though I still have to
write
    db.session.query(Counter).all()
instead of the much nicer
    Counter.query.all()
but maybe one day I'll figure that out too.

Gabor

On Thu, May 13, 2021 at 4:57 PM Gabor Szabo <gabor at szabgab.com> wrote:

> Nicolas, thanks. That helped a lot and I managed to write a full example
> that shows this: https://code-maven.com/flask-counter-sqlite-sqlalchemy
>
>
> However I still have an issue. We use yoyo to manage migrations and I
> wanted to try the automap feature of SQLAlchemy.  I could not solve it
> elegantly just this way:
> https://code-maven.com/flask-counter-sqlite-sqlalchemy-yoyo
>
> * There is a "global" in the model.py
> * I could not figure out how to create the classes for the table(s) so I
> added them to a "base" class.
> * I had to change the query code from Counter.query.all()
>
> Any suggestions there?
>
> Gabor
>
> On Wed, May 12, 2021 at 12:12 PM Nicolas Le Manchet <nicolas at lemanchet.fr>
> wrote:
>
>> Hi,
>>
>> You should take a look at application factories (
>> https://flask.palletsprojects.com/en/1.1.x/patterns/appfactories/). It's
>> a pattern that allows to have multiple applications configured differently
>> in the same interpreter, which tends to make testing easier.
>>
>> On Wed, May 12, 2021, at 11:00, Gabor Szabo wrote:
>> > Hi,
>> >
>> > I am working on an application using Flask-sqlalchemy and I am not sure
>> > how to write tests properly.
>> >
>> > In all the examples I have seen so far the main flask file has the line
>> >
>> >     db = SQLAlcehmy(app)
>> >
>> > meaning this is executed when the main file of Flask is loaded. so if
>> > the test file has
>> >
>> >     import app
>> >
>> > that would still happen at compile time. This way I have only one
>> > chance to set up a test-database , right before that import-statement.
>> >
>> > In order to make it easier to use different test database we moved the
>> >     db = SQLAlcehmy(app)
>> > call inside a function decorated with before_first_request.
>> > This ensures the code is called for regular use and we can call the
>> > before_first_request method for each test. Because we don't have db at
>> > load time we also had to move all the class-declarations in this
>> > function (because they all inherit from db.Model).
>> >
>> > The problem is that now all the model classes are scoped to this
>> > function. We had to use "global" to make them accessible to the rest of
>> > the code.
>> >
>> > That does not look right.
>> >
>> > The code can be found here: https://github.com/rnewstead1/workout-app/
>> > (together with the tests)
>> > And you can actually see our struggle in this video:
>> > https://code-maven.com/workout-app-2
>> >
>> > I'd appreciate your insight on how to make this nicer or even just a
>> > link to a code-base that has such tests.
>> >
>> > Gabor
>>
>>
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