crd-docs-generator

crd-docs-generator

Generates schema reference documentation for Kubernetes Custom Resource Definitions (CRDs).

This tool is built to generate our Management API schema reference in https://docs.giantswarm.io/reference/cp-k8s-api/.

The generated output consists of Markdown files packed with HTML. By itself, this does not provide a fully readable and user-friendly set of documentation pages. Instead it relies on the HUGO website context, as the giantswarm/docs repository, to provide an index page and useful styling.

Assumptions/Prerequisites

This tool relies on:

• CRDs being defined in the giantswarm/apiextensions repository
• ... as one YAML file per CRD in the apiextensions config/crd/v1 folder folder.
• CRDs providing an OpenAPIv3 validation schema
  • either in the .spec.validation section of a CRD containg only one version
  • or in the .spec.versions[*].schema position of a CRD containing multiple versions
• OpenAPIv3 schemas containing description attributes for every property.
• The topmost description value explaining the CRD itself. (For a CRD containing multiple versions, the first description found is used as such.)
• CR examples to be found in the apiextensions docs/cr folder as one example per YAML file.

Usage

The generator can be executed in Docker using a command like this:

docker run \
    -v $PWD/path/to/output-folder:/opt/crd-docs-generator/output \
    -v $PWD:/opt/crd-docs-generator/config \
    quay.io/giantswarm/crd-docs-generator \
      --config /opt/crd-docs-generator/config/config.yaml

or in Go like this:

go run main.go --config service/config/testdata/config1.yaml

The volume mapping defines where the generated output will land.

TODO

• Parse template only once instead of for every CRD