check mode for CI runs

[sebhoss]

It would be cool to have a check mode that verifies that a given schema matches the one generated through the given inputs. This could be used to verify that developers did not forget to re-generate a schema when they change inputs.

[losisin]

@sebhoss Is there anything missing your use case from integration section is README.md file?

[sebhoss]

We don't use GitHub but GitLab - I'm basically asking for the fail-on-diff feature of the GitHub action to be available in the CLI itself

[losisin]

@sebhoss thank you for the suggestion! It sure sounds as reasonable request. I'm afraid best option for now is pre-commit hook even though it's hard to verify that every developer has installed it. I can't promise anything short-term but maybe in some future release we can add some kind of validations with CLI flags to be used in CI/CD.
Sounds good?

[sebhoss]

Yeah of course! I have written a small script that performs the comparison in our pipelines so I don't have an immediate need for it anymore.

That said, would a -check flag that instructs the CLI to compare its generated output with what is inside -output instead of writing to that file be of interest to you?

[losisin]

@sebhoss Since you mentioned that you already have a script, the most efficient way would be to add section under integrations in README.md as generic CI example

[sebhoss]

It's not really generic and kinda involved in our case since we are using GitLab components, but a trimmed down version looks like this:

schema-check:
  script:
    - cd path/to/helm/chart
    - helm schema -output generated-schema.json
    - CURRENT_SCHEMA=$(cat values.schema.json)
    - GENERATED_SCHEMA=$(cat generated-schema.json)
    - |
      if [ "$CURRENT_SCHEMA" != "$GENERATED_SCHEMA" ]; then
        echo "Schema must be re-generated! Run 'helm schema' in the helm-chart directory" 1>&2
        exit 1
      fi