Ability to reference multiple types / generate resources multiple times

[Breee]

What problem are you facing?

• The keycloak provider is generated via upjet
• I'm currently facing the issue that the terraform provider uses generic types under the hood, for example for Clients
• In reality we have OpenID Client and Saml Client and sadly no Generic Client available as resource.
• This leads to problems when i have to create references for resources which just reference a Client, which can be both OpenId Client or Saml Client
• The upstream Terraform provider is dying and is unmaintained

How could Upjet help solve your problem?

• I'm looking for a way to have references to either a Generic Type or multiple Types OR just generate a resource multiple times with different Kinds + References
• simplified example:

r.References["client_id"] = config.Reference{
	Type:  []{"github.com/crossplane-contrib/provider-keycloak/apis/openidclient/v1alpha1.Client", "github.com/crossplane-contrib/provider-keycloak/apis/samlclient/v1alpha1.Client},
	}

• Or allow to do something like:

package v1alpha

type GenericClient interface { 
  *OpenIDClient | *SamlCLient
}

• Also: as i see there is no working way to generate the same resource twice, which would be ugly but feasible (and loopable): Both do not work

	p.AddResourceConfigurator("keycloak_generic_protocol_mapper", func(r *config.Resource) {
		r.ShortGroup = "client"
		r.Name = "keycloak_generic_protocol_mapper"
		r.Kind = "OpenIDProtocolMapper"
		r.References["client_scope_id"] = config.Reference{
			Type: "github.com/crossplane-contrib/provider-keycloak/apis/openidclient/v1alpha1.ClientScope",
		}
	})

	p.AddResourceConfigurator("keycloak_generic_protocol_mapper", func(r *config.Resource) {
		r.ShortGroup = "client"
		r.Name = "keycloak_generic_protocol_mapper"
		r.Kind = "SamlProtocolMapper"
		r.References["client_scope_id"] = config.Reference{
			Type: "github.com/crossplane-contrib/provider-keycloak/apis/samlclient/v1alpha1.ClientScope",
		}
	})

	// Configure keycloak_generic_protocol_mapper for OpenIdProtocolMapper
	openIdConfigurator := ujconfig.ResourceConfiguratorFn(func(r *ujconfig.Resource) {
		r.ShortGroup = Group
		r.Name = "keycloak_generic_protocol_mapper"
		r.Kind = "OpenIdProtocolMapper"
		r.References["client_scope_id"] = ujconfig.Reference{
			Type: "github.com/crossplane-contrib/provider-keycloak/apis/openid/v1alpha1.ClientScope",
		}
	})
	// Configure keycloak_generic_protocol_mapper for SamlProtocolMapper
	samlConfigurator := ujconfig.ResourceConfiguratorFn(func(r *ujconfig.Resource) {
		r.ShortGroup = Group
		r.Name = "keycloak_generic_protocol_mapper"
		r.Kind = "SamlProtocolMapper"
		r.References["client_scope_id"] = ujconfig.Reference{
			Type: "github.com/crossplane-contrib/provider-keycloak/apis/saml/v1alpha1.ClientScope",
		}
	})

	p.SetResourceConfigurator("keycloak_generic_protocol_mapper", ujconfig.ResourceConfiguratorChain{openIdConfigurator, samlConfigurator})

code is also on this branch: https://github.com/crossplane-contrib/provider-keycloak/blob/dfacf3ae92d66b1df511884113858be1636b1327/config/mapper/config.go#L59

[yordis]

@Breee could this help me with crossplane-contrib/provider-upjet-digitalocean#36 as well? I am trying to figure out what is the best strategy to deal with more than one type for a given resource field

[yordis]

Also Type is deprecated so it would be TerraformName

[Breee]

I'm not sure, maybe maintainers @muvaf or @ulucinar can tell us if that is even possible

[artemlive]

Are there any updates?
I've encountered the same problem when I have multiple types for one field.

[Breee]

Not yet, the Best solution I came up with is writing a custom Controller that implements both types or use a composition function that selects the Type based on some property passed.

[artemlive]

@Breee, thanks for the reply.
I'm curious, is it possible to mutate schema to make a few separate fields and, depending on the type (that can be a separate string field) use the corresponding field reference? (without compositions)
Pseudocode:

func CustomExtractor(ctx context.Context, mg resource.Managed) (string, error) {
    // Cast the resource to your specific type
    obj, ok := mg.(*MyResource)
    if !ok {
        return "", fmt.Errorf("unexpected resource type: %T", mg)
    }

    // Iterate over the responders to find the type and map it accordingly
    for _, responder := range obj.Spec.ForProvider.Create.Responders {
        switch responder.Type {
        case "team":
            return responder.TeamID, nil
        case "user":
            return responder.UserID, nil
        case "escalation":
            return responder.EscalationID, nil
        default:
            return "", fmt.Errorf("unsupported type: %s", responder.Type)
        }
    }

    return "", fmt.Errorf("no valid responder type found")
}

Sorry if it looks stupid. I'm new to upjet generators.