Custom Converter Design

[hongchaodeng]

Here's the design on top of my mind:

type v1alpha1Component Unstructured
type v1alpha2Component Unstructured
...

// Converter is the plugin that convert v1alpha1 OAM types to v1alpha2 types
type Converter interface {
    // ConvertComponent converts v1alpha1 Component in ApplicationConfiguration to
    // v1alpha2 Component and workload CR.
    ConvertComponent(v1alpha1Component) (v1alpha2Component)

    // ConvertTrait converts v1alpha1 Trait in ApplicationConfiguration to trait CR.
    ConvertTrait(v1alpha1Trait) (v1alpha2Trait)
}

[My-pleasure]

converter/converter.go:

• An interface defines a collection of methods: https://github.com/My-pleasure/oam-crd-migration/blob/b136b12b5bcba9cd292736abeb6a6b447a83b14d/converter/converter.go#L15
• Method receiver: https://github.com/My-pleasure/oam-crd-migration/blob/b136b12b5bcba9cd292736abeb6a6b447a83b14d/converter/converter.go#L24
• Method implementation: https://github.com/My-pleasure/oam-crd-migration/blob/b136b12b5bcba9cd292736abeb6a6b447a83b14d/converter/converter.go#L27 https://github.com/My-pleasure/oam-crd-migration/blob/b136b12b5bcba9cd292736abeb6a6b447a83b14d/converter/converter.go#L46

converter/framework.go:

• Define handler functions: https://github.com/My-pleasure/oam-crd-migration/blob/b136b12b5bcba9cd292736abeb6a6b447a83b14d/converter/framework.go#L240

main.go:

• Register handler functions: https://github.com/My-pleasure/oam-crd-migration/blob/b136b12b5bcba9cd292736abeb6a6b447a83b14d/main.go#L52