Remove backend packages

[duckontheweb]

Related Issue(s):

• Split backends into independent repos #432

Description:

• Removes backend-specific code, configuration, and documentation
  Going forward, the SQLAlchemy and PgSTAC backends will be distributed as separate packages and managed in their own repos (stac-fastapi-sqlalchemy and stac-fastapi-pgstac, respectively). The main Dockerfile and docker-compose.yml have been removed since there is no longer a deployable backend associated with this repo.
• Distributes stac-fastapi.api, stac-fastapi.types, and stac-fastapi.extensions as modules under a single stac-fastapi package.
  Import statements for the individual modules will not change, but downstream applications will need to update their dependency from something like...

  stac-fastapi.api==2.4.1
  stac-fastapi.types==2.4.1
  stac-fastapi.extensions==2.4.1
  

  ...to something like...

  stac-fastapi==2.5.0
  

PR Checklist:

• Code is formatted and linted (run pre-commit run --all-files)
• Tests pass (run make test)
• Documentation has been updated to reflect changes, if applicable, and docs build successfully (run make docs)
• Changes are added to the CHANGELOG.
• Remove or add CI to implement validation checks

[geospatial-jeff]

A few more comments, typing them out here because there isn't a great place to comment in the diff.

• The test data at tests/data/joplin probably isn't used anywhere, but maybe its nice to keep around?
• Can remove the alembic exclude from the find_namespace_packages call in setup.py.

I'm starting on the sqlalchemy backend today, if I find anything else I'll add here.

[duckontheweb]

• The test data at tests/data/joplin probably isn't used anywhere, but maybe its nice to keep around?

Yeah, it might make sense to keep it around for now. I'm thinking that as we expand the test suite we may want a simple backend mocker that just reads files from a directory. Having these files available would probably make that easier to put together in the future.

[duckontheweb]

• Can remove the alembic exclude from the find_namespace_packages call in setup.py.

Fixed in 2d72c58

[gadomski]

NB there have been some changes to backend-specific code that were dropped by 22d6a01, so we will need to go back and backport any of those to the backend-specific repos (if they haven't been backported already).

[gadomski]

Since this appears to have stalled out, I've made an RFC with a plan to finish the backend breakout. Tl;dr: I'm proposing we punt on the separation of responsibilities (e.g. #453) -- while it's a good idea, it's becoming a blocker that's holding the stac-fastapi ecosystem in an undefined state. While we might end up with pain down the road to synchronize the backend repos with the main ones, it's my hope that we can use API breakages v3.0 to solve the separation of concerns in the medium-term.

[geospatial-jeff]

@gadomski That makes sense to me, we can always come back to these changes in the future in a later major version. I think the more important thing is getting the backends split out, regardless of the separation of concerns.

EDIT: Found it #517