Tool for Generating Trigger Schema

[SpiritZhou]

Proposal

Generating trigger metadata schema according to new declarative scaler configuration, which can be used for validation or other related improvement.

Input:
make generate-trigger-metadata-schema [--triggername][--output][--outputfile]

Output:
trigger-metadata-schemas.yaml

Trigger metadata example:

- type: kubernetes-workload
  metadatafields:
    activationValue:
        type: string
        default: "0"
    podSelector:
        type: string
    value:
        type: string
        default: "0"
- type: activemq
  metadatafields:
    activationTargetQueueSize:
      type: string
      optional: "true"
      default: "0"
    brokerName:
      type: string
      optional: "true"
    corsHeader:
      type: string
      optional: "true"
    destinationName:
      type: string
      optional: "true"
    managementEndpoint:
      type: string
      optional: "true"
    password:
      type: string
    passwordFromEnv:
      type: string
    restAPITemplate:
      type: string
      optional: "true"
    targetQueueSize:
      type: string
      optional: "true"
      default: "10"
    username:
      type: string
    usernameFromEnv:
      type: string

Use-Case

No response

Is this a feature you are interested in implementing yourself?

Yes

Anything else?

No response

[wozniakjan]

the tricky part is that technically all metadata fields are string in the CRD definition despite the underlying type. The OpenAPI schema allows setting multiple types for a field, maybe we can leverage that in some way?
https://stackoverflow.com/questions/46472543/specifying-multiple-types-for-additionalproperties-through-swagger-openapi

We would likely need to change the map[string]string to map[string]any but this theoretically shouldn't be a breaking change.