Project-targeted Schemathesis test and OpenAPI schema fix

[juhoinkinen]

PR #682 introduced Schemathesis for testing REST API. However, as noted in https://github.com/NatLibFi/Annif/pull/664#issuecomment-1476336156, Schemathesis creates random path (and query) parameters, which means most of the test requests target non-existent projects giving just 404 error.

This PR adds a test that targets the methods in the endpoint /v1/projects/{project_id}* and uses a fixed project-id dummy-fi. A project with this id exists, so the test requests probe the actions that are (mostly) missed otherwise.

This test noted two attributes in the OpenAPI specification that should be required or nullable, which are fixed. openapi-diff tool tool complains that the fixes break backward compatibility:

==========================================================================
==                            API CHANGE LOG                            ==
==========================================================================
                              Annif REST API                              
--------------------------------------------------------------------------
--                            What's Changed                            --
--------------------------------------------------------------------------
- POST   /projects/{project_id}/learn
  Request:
        - Changed application/json
          Schema: Broken compatibility
--------------------------------------------------------------------------
--                                Result                                --
--------------------------------------------------------------------------
                 API changes broke backward compatibility                 
--------------------------------------------------------------------------

However I think the fixes should be harmless for backward compatibility and should be done:

• notation in SuggestionResult should be nullable because it is None if the vocabulary does not contain notations, which usually is the case
• uri in subjects of IndexedDocument should be required because otherwise Internal error due to KeyError: 'uri' occurs

At first I thought that also text and subjects in IndexedDocument should be required, but maybe not, at least that case is covered with an if condition:https://github.com/NatLibFi/Annif/blob/4bf5610219e3e2dd23a0e0464b834338f0465009/annif/rest.py#L116

Also, this test is quite slow (10-15 s) and when the suggest-batch endpoint will be added it becomes even slower (20-25 s), so I marked it "slow" with a pytest decorator and configured pytest to skip it by default. It can be run using -m slow option:

 pytest -m slow

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Codecov Report

Patch coverage: 100.00% and no project coverage change.

Comparison is base (4bf5610) 99.57% compared to head (3f25671) 99.57%.

Additional details and impacted files

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[osma]

Changes to the schema look OK and necessary.

Regarding slow tests: it's good to not run them by default, but what about GitHub Actions CI? Now it seems they will also not be run under Actions, which Codecov complains about. I think it would make sense to run them there, otherwise nobody will ever remember to run them.

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0 Bugs
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No Coverage information
0.0% Duplication

[juhoinkinen]

The new slow Schemathesis test is now a bit faster as it uses only 50 examples (which was enough to capture the now-fixed schema shortcomings).

Also I set the test to be run in the Python 3.9 GH Actions job, which has been the fastest one, so now jobs for different Python versions take about the same time.