Adapt code to prevent new warnings and errors (as of SQLAlchemy 1.4):
- Overlapping foreign key columns could be set in a conflicting way
=> This is prevented by the application logic
=> Ignore the warning by setting a `overlaps` flag
- Transaction already rolled back
=> This only happens when tests cause an `IntegrityError` on purpose
=> Filter away the corresponding warning in the fixture
- Query returns `Row` objects and not scalars
=> Add genexpr to pull out `primary_id`
- reorganize `urban_meal_delivery.console` into a sub-package
- move `tests.db.conftest` fixtures into `tests.conftest`
=> some integration tests regarding CLI scripts need a database
- add `urban_meal_delivery.console.decorators.db_revision` decorator
to ensure the database is at a certain state before a CLI script runs
- refactor the `urban_meal_delivery.db.grids.Grid.gridify()` constructor:
- bug fix: even empty `Pixel`s end up in the database temporarily
=> create `Pixel` objects only if an `Address` is to be assigned
to it
- streamline code and docstring
- add further test cases
- use Alembic to migrate the PostgreSQL database
+ create initial migration script to set up the database,
as an alternative to db.Base.metadata.create_all()
+ integrate Alembic into the test suite; the db_engine fixture
now has two modes:
* create the latest version of tables all at once
* invoke `alembic upgrade head`
=> the "e2e" tests are all run twice, once in each mode; this
ensures that the migration scripts re-create the same database
schema as db.Base.metadata.create_all() would
* in both modes, a temporary PostgreSQL schema is used to create the
tables in
=> could now run "e2e" tests against production database and still
have isolation
- make the configuration module public (to be used by Alembic)
- adjust linting rules for Alembic
