Get database url from .env instead of .ini file

[Zaffer]

Surely it is better practice to load the sqlalchemy URL from the .env file compared to the .ini file.

Can we please make a env.py template that simply loads in the URL from a more robust .env variable instead of needing to save the url into a .ini file that will be part of the repo and have secrets stored in it...

[CaselIT]

Please note that you are free to modify the env file however it pleases you, the templates are just example that can be used as base

[zzzeek]

from https://alembic.sqlalchemy.org/en/latest/tutorial.html#the-migration-environment, relevant emphasis highlighted:

env.py - This is a Python script that is run whenever the alembic migration tool is invoked. At the very least, it contains instructions to configure and generate a SQLAlchemy engine, procure a connection from that engine along with a transaction, and then invoke the migration engine, using the connection as a source of database connectivity.

The env.py script is part of the generated environment so that the way migrations run is entirely customizable. The exact specifics of how to connect are here, as well as the specifics of how the migration environment are invoked. The script can be modified so that multiple engines can be operated upon, custom arguments can be passed into the migration environment, application-specific libraries and models can be loaded in and made available.