Optional integrations - Githubissues

javierdelapuente commented 5 months ago

Applicable spec:

Overview

This PR uses the optional attribute in the requires key in the charmcraft.yaml file. If optional attribute is false for a declared integration, and that integration is not integrated or not correctly integrated, the charm blocks.

For this PR, a refactor of how the integrations that can be optional work has been done. Now the CharmState has a field integrations that includes the integrations following a common API, Integration, that has two main methods:

gen_environment: Return the environment variables for the 12-factor app.
block_charm: If the charm should be blocked because of this integrations (because it is not integrated or the integrations is someway wrong).

With this refactor, new integrations should be a little easier and more consistent.

Rationale

Currently, integrations do not block the charm, except if the --check-config check fails.

For example, an application that requires a database or Redis can become active, even if it is not working. The natural way of Juju to work is to block the charm until the required integrations are correctly integrated, otherwise blocking the charm (see https://juju.is/docs/juju/status#heading--application-status).

This way, the charm developer can, in a very simple way, declare if the integration is optional or not for the charm, and the charm will wait until at least all the required integrations are ready.

Juju Events Changes

Module Changes

Library Changes

Checklist

[x] The charm style guide was applied
[x] The contributing guide was applied
[x] The changes are compliant with ISD054 - Managing Charm Complexity
[x] The documentation is generated using src-docs
[x] The documentation for charmhub is updated
[x] The PR is tagged with appropriate label (urgent, trivial, complex)

github-actions[bot] commented 5 months ago

Test coverage for b6b5b09252580f963c9a7454bdbfa1cf8c646dac

Name                                           Stmts   Miss Branch BrPart  Cover   Missing
------------------------------------------------------------------------------------------
paas_app_charmer/__init__.py                       0      0      0      0   100%
paas_app_charmer/_gunicorn/__init__.py             0      0      0      0   100%
paas_app_charmer/_gunicorn/charm.py              127     23     26      4    81%   59-61, 174-175, 177-178, 198->exit, 208-212, 236-238, 243-244, 248, 252, 256, 264, 268, 272, 276, 280
paas_app_charmer/_gunicorn/charm_state.py         57      1      6      1    97%   185
paas_app_charmer/_gunicorn/observability.py       19      0      0      0   100%
paas_app_charmer/_gunicorn/secret_storage.py      13      0      0      0   100%
paas_app_charmer/_gunicorn/webserver.py           75      5     16      2    92%   19, 155, 167-173
paas_app_charmer/_gunicorn/wsgi_app.py            60      0     24      0   100%
paas_app_charmer/database_migration.py            33      0      2      0   100%
paas_app_charmer/databases.py                     18      0      4      0   100%
paas_app_charmer/django/__init__.py                1      0      0      0   100%
paas_app_charmer/django/charm.py                  44     13     10      0    65%   72-77, 89, 97-114
paas_app_charmer/exceptions.py                     4      0      0      0   100%
paas_app_charmer/flask/__init__.py                 1      0      0      0   100%
paas_app_charmer/flask/charm.py                   36      0      6      0   100%
paas_app_charmer/integrations.py                  51      0      9      0   100%
paas_app_charmer/secret_storage.py                39      3     16      5    85%   50, 54->53, 55->57, 85, 104
------------------------------------------------------------------------------------------
TOTAL                                            578     45    119     12    91%

Static code analysis report

Run started:2024-05-29 13:33:45.478986

Test results:
    No issues identified.

Code scanned:
    Total lines of code: 1315
    Total lines skipped (#nosec): 0
    Total potential issues skipped due to specifically being disabled (e.g., #nosec BXXX): 0

Run metrics:
    Total issues (by severity):
        Undefined: 0
        Low: 0
        Medium: 0
        High: 0
    Total issues (by confidence):
        Undefined: 0
        Low: 0
        Medium: 0
        High: 0
Files skipped (0):