Show police department on the image and tag detail pages

[redshiftzero]

Status

Ready for review

Description of Changes

Fixes #305.

Changes proposed in this pull request:

• Adds foreign key constraint (and migration) between images and departments tables
• Shows the police department on the image page:

Testing / Deployment

Tests and linting

• I have rebased my changes on current develop

• pytests pass in the development environment on my local machine

• flake8 checks pass

[r4v5]

It may just be a thing that's done magically by sqlalchemy but doesn't the raw_images.department_id column need to be populated (presumably with '1' for the first department for existing images) in order to not violate the constraint you'll be imposing on it?

Also, did I miss the place where uploaded raw_images will have the department ID set on them (possibly in another PR)? Because an insert without a department_id will cause a FK constraint violation.

[r4v5]

Ah: for the first one, there's a manage.py task added in #310 (f686248) to address it, which I think probably should be pulled into this branch, since it's technically part of this change ('image-related things'). And the image upload route is part of the previous changeset. Okay cool.

[redshiftzero]

You probably figured this out hence the merge, but writing out here for posterity:

doesn't the raw_images.department_id column need to be populated (presumably with '1' for the first department for existing images) in order to not violate the constraint you'll be imposing on it?

Yep! The manage.py link_images_to_department command was added in #303 to handle this (a bit hacky maybe, but 🤷‍♀️). I added a similar command in #310 for doing the same thing with two other tables that should store department_id (in prep for adding a foriegn key constraint later on).

[redshiftzero]

Ohh I see ya moved that bit o' code over here. That's 💯