feat: Make alembic version table configurable

[gdiepen]

If the environment variable OIDC_ALEMBIC_VERSION_TABLE is defined, use this as the table that alembic uses to store the alembic versions in. If not defined, use the default alembic_version.

Fixes: #76

Allows to use both mlflow-oidc-auth and mlflow in the same (postgres) database, each having its own alembic version table.

[gdiepen]

I am running this in a local development branch and with this modification I am now running both mlflow and the plugin inside the same postgres database

[kharkevich]

Hi @gdiepen,
thanks for your PR, could you please update it to use mlflow_oidc_auth/config.py for configuration of this feature
do not forget to update tests as well please

[gdiepen]

Will check what needs to be changed to use mlflow_oidc_auth/config.py there

Also will try to see how to write the test for this

[gdiepen]

So the first part is done, I have moved everything to the config and use that.

Second part I am having some problems with, not familiar with python unittest (a bit more experience with pytest).

Getting stuck on how to ensure I can initialize an empty database and see if the table created is based on the os environment.....

[gdiepen]

@kharkevich If you understand what is going wrong here, that would be very useful

If I use :memory: for the create_engine function in line 49, like this

the tables list is always empty.

However, if I change it to engine = create_engine("sqlite:///foo.db"), then it does work.

Second question would be how to mock environment variable in this framework, such that I can create a second test where I let it be a custom alembic version table

[gdiepen]

@kharkevich Having the migration run inside of a temporary database would be the nicest unit test (but still stuck on trying to get the alembic unit test to work with :memory: database....) I could just do a unit test of only checking the value in the config object, not sure which test you would like more. If you want to have the full in-memory test, do you have any idea on how this works?