add backend service reference

apis/compute/v1beta1/forwardingrule_types.go

@@ -144,7 +144,7 @@ type ComputeForwardingRuleSpec struct {
 	/* A ComputeBackendService to receive the matched traffic. This is
 	used only for internal load balancing. */
 	// +optional
-	BackendServiceRef *refs.ComputeBackendServiceRef `json:"backendServiceRef,omitempty"`
+	BackendServiceRef *ComputeBackendServiceRef `json:"backendServiceRef,omitempty"`
 
 	/* Immutable. An optional description of this resource. Provide this property when
 	you create the resource. */

apis/compute/v1beta1/targettcpproxy_types.go

@@ -15,7 +15,6 @@
 package v1beta1
 
 import (
-	refs "github.com/GoogleCloudPlatform/k8s-config-connector/apis/refs/v1beta1"
 	"github.com/GoogleCloudPlatform/k8s-config-connector/pkg/apis/k8s/v1alpha1"
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
 	"k8s.io/apimachinery/pkg/runtime/schema"
@@ -34,7 +33,7 @@ var (
 type ComputeTargetTCPProxySpec struct {
 	// A reference to the ComputeBackendService resource.
 	// +required
-	BackendServiceRef *refs.ComputeBackendServiceRef `json:"backendServiceRef"`
+	BackendServiceRef *ComputeBackendServiceRef `json:"backendServiceRef"`
 
 	// +kubebuilder:validation:XValidation:rule="self == oldSelf",message="Description is immutable"
 	// Immutable. An optional description of this resource.

apis/refs/v1beta1/computerefs.go

@@ -256,15 +256,6 @@ type ComputeAddressRef struct {
 	Namespace string `json:"namespace,omitempty"`
 }
 
-type ComputeBackendServiceRef struct {
-	/* The ComputeBackendService selflink in the form "projects/{{project}}/global/backendServices/{{name}}" or "projects/{{project}}/regions/{{region}}/backendServices/{{name}}" when not managed by Config Connector. */
-	External string `json:"external,omitempty"`
-	/* The `name` field of a `ComputeBackendService` resource. */
-	Name string `json:"name,omitempty"`
-	/* The `namespace` field of a `ComputeBackendService` resource. */
-	Namespace string `json:"namespace,omitempty"`
-}
-
 type ComputeServiceAttachmentRef struct {
 	/* The ComputeServiceAttachment selflink in the form "projects/{{project}}/regions/{{region}}/serviceAttachments/{{name}}" when not managed by Config Connector. */
 	External string `json:"external,omitempty"`

apis/refs/v1beta1/helper.go

@@ -15,8 +15,14 @@
 package v1beta1
 
 import (
+	"context"
 	"fmt"
 
+	"github.com/GoogleCloudPlatform/k8s-config-connector/pkg/k8s"
+	apierrors "k8s.io/apimachinery/pkg/api/errors"
+	"k8s.io/apimachinery/pkg/runtime/schema"
+	"sigs.k8s.io/controller-runtime/pkg/client"
+
 	"k8s.io/apimachinery/pkg/apis/meta/v1/unstructured"
 )
 
@@ -41,3 +47,16 @@ func GetLocation(u *unstructured.Unstructured) (string, error) {
 	}
 	return location, nil
 }
+
+func ResolveResourceName(ctx context.Context, reader client.Reader, key client.ObjectKey, gvk schema.GroupVersionKind) (*unstructured.Unstructured, error) {
+	resource := &unstructured.Unstructured{}
+	resource.SetGroupVersionKind(gvk)
+	if err := reader.Get(ctx, key, resource); err != nil {
+		if apierrors.IsNotFound(err) {
+			return nil, k8s.NewReferenceNotFoundError(resource.GroupVersionKind(), key)
+		}
+		return nil, fmt.Errorf("error reading referenced %v %v: %w", gvk.Kind, key, err)
+	}
+
+	return resource, nil
+}

apis/refs/v1beta1/interface.go

@@ -20,6 +20,15 @@ import (
 	"sigs.k8s.io/controller-runtime/pkg/client"
 )
 
+type ReferenceContext struct {
+	// Whether a referenced resource is only managed by direct controller
+	IsDirectOnly bool
+
+	// the referenced resource's field that will be extracted and set as the value of referenced field
+	// If IsDirectOnly is false, TargetField is required
+	TargetField string
+}
+
 type ExternalNormalizer interface {
 	// NormalizedExternal expects the implemented struct has a "External" field, and this function
 	// assigns a value to the "External" field if it is empty.

config/crds/resources/apiextensions.k8s.io_v1_customresourcedefinition_computeforwardingrules.compute.cnrm.cloud.google.com.yaml

@@ -113,16 +113,15 @@ spec:
                   - external
                 properties:
                   external:
-                    description: The ComputeBackendService selflink in the form "projects/{{project}}/global/backendServices/{{name}}"
-                      or "projects/{{project}}/regions/{{region}}/backendServices/{{name}}"
-                      when not managed by Config Connector.
+                    description: The value of an externally managed ComputeBackendService
+                      resource. Should be in the format "projects/{{project}}/global/backendServices/{{backendService}}"
+                      or "projects/{{project}}/regions/{{region}}/backendServices/{{backendService}}".
                     type: string
                   name:
-                    description: The `name` field of a `ComputeBackendService` resource.
+                    description: The name of a ComputeBackendService resource.
                     type: string
                   namespace:
-                    description: The `namespace` field of a `ComputeBackendService`
-                      resource.
+                    description: The namespace of a ComputeBackendService resource.
                     type: string
                 type: object
               description:

config/crds/resources/apiextensions.k8s.io_v1_customresourcedefinition_computetargettcpproxies.compute.cnrm.cloud.google.com.yaml

@@ -80,16 +80,15 @@ spec:
                   - external
                 properties:
                   external:
-                    description: The ComputeBackendService selflink in the form "projects/{{project}}/global/backendServices/{{name}}"
-                      or "projects/{{project}}/regions/{{region}}/backendServices/{{name}}"
-                      when not managed by Config Connector.
+                    description: The value of an externally managed ComputeBackendService
+                      resource. Should be in the format "projects/{{project}}/global/backendServices/{{backendService}}"
+                      or "projects/{{project}}/regions/{{region}}/backendServices/{{backendService}}".
                     type: string
                   name:
-                    description: The `name` field of a `ComputeBackendService` resource.
+                    description: The name of a ComputeBackendService resource.
                     type: string
                   namespace:
-                    description: The `namespace` field of a `ComputeBackendService`
-                      resource.
+                    description: The namespace of a ComputeBackendService resource.
                     type: string
                 type: object
               description:

pkg/controller/direct/compute/forwardingrule/forwardingrule_controller.go

@@ -27,6 +27,7 @@ import (
 	gcp "cloud.google.com/go/compute/apiv1"
 	computepb "cloud.google.com/go/compute/apiv1/computepb"
 	krm "github.com/GoogleCloudPlatform/k8s-config-connector/apis/compute/v1beta1"
+	refsv1beta1 "github.com/GoogleCloudPlatform/k8s-config-connector/apis/refs/v1beta1"
 	"github.com/GoogleCloudPlatform/k8s-config-connector/pkg/config"
 	"github.com/GoogleCloudPlatform/k8s-config-connector/pkg/controller/direct"
 	"github.com/GoogleCloudPlatform/k8s-config-connector/pkg/controller/direct/directbase"
@@ -539,3 +540,39 @@ func setStatus(u *unstructured.Unstructured, typedStatus any) error {
 
 	return nil
 }
+
+// This function get the normalized external values and convert it to the API required format
+func resolveBackendService(ctx context.Context, reader client.Reader, obj *krm.ComputeForwardingRule) error {
+	// API required format: selfLink
+	referenceContext := refsv1beta1.ReferenceContext{IsDirectOnly: false, TargetField: "status.selfLink"}
+	computeBasePath := "https://www.googleapis.com/compute/v1/"
+	ref := obj.Spec.BackendServiceRef
+	if ref != nil {
+		// Get normalized external
+		_, err := ref.NormalizedExternal(ctx, reader, obj.GetNamespace())
+		if err != nil {
+			return fmt.Errorf("failed to get BackendServiceRef: %w", err)
+		}
+		// Convert normalized external to API required format
+		v := ref.External
+		// If object is DirectOnly, it is created by direct controller.
+		if referenceContext.IsDirectOnly {
+			// add the compute prefix in front
+			obj.Spec.BackendServiceRef.External = computeBasePath + v
+			return nil
+		}
+		// If object not DirectOnly, it can be created by either direct controller or legacy controller, depends on user's settings.
+		_, _, err = krm.ParseComputeBackendServiceExternal(v)
+		// Value follows KCC external format, likely it's created by direct controller
+		if err == nil {
+			// add the compute prefix in front
+			obj.Spec.BackendServiceRef.External = computeBasePath + v
+			return nil
+		}
+		// For backward compatibility, we also accept values that does not match the KCC external format.(likely it's created by legacy controller)
+		// Return the value as is and let the API handle it
+		obj.Spec.BackendServiceRef.External = v
+		return nil
+	}
+	return nil
+}

pkg/controller/direct/compute/forwardingrule/mapper.go

@@ -52,16 +52,16 @@ func ComputeForwardingRuleSpec_IpAddress_FromProto(mapCtx *direct.MapContext, in
 	return out
 }
 
-func ComputeForwardingRuleSpec_BackendSeriviceRef_FromProto(mapCtx *direct.MapContext, in string) *refs.ComputeBackendServiceRef {
+func ComputeForwardingRuleSpec_BackendSeriviceRef_FromProto(mapCtx *direct.MapContext, in string) *krm.ComputeBackendServiceRef {
 	if in == "" {
 		return nil
 	}
-	return &refs.ComputeBackendServiceRef{
+	return &krm.ComputeBackendServiceRef{
 		External: in,
 	}
 }
 
-func ComputeForwardingRuleSpec_BackendSeriviceRef_ToProto(mapCtx *direct.MapContext, in *refs.ComputeBackendServiceRef) *string {
+func ComputeForwardingRuleSpec_BackendSeriviceRef_ToProto(mapCtx *direct.MapContext, in *krm.ComputeBackendServiceRef) *string {
 	if in == nil {
 		return nil
 	}

pkg/controller/direct/compute/forwardingrule/refs.go

@@ -178,49 +178,6 @@ func ResolveComputeAddress(ctx context.Context, reader client.Reader, src client
 		External: address}, nil
 }
 
-func ResolveComputeBackendService(ctx context.Context, reader client.Reader, src client.Object, ref *refs.ComputeBackendServiceRef) (*refs.ComputeBackendServiceRef, error) {
-	if ref == nil {
-		return nil, nil
-	}
-
-	if ref.External != "" {
-		if ref.Name != "" {
-			return nil, fmt.Errorf("cannot specify both name and external on reference")
-		}
-		return ref, nil
-	}
-
-	if ref.Name == "" {
-		return nil, fmt.Errorf("must specify either name or external on reference")
-	}
-
-	key := types.NamespacedName{
-		Namespace: ref.Namespace,
-		Name:      ref.Name,
-	}
-	if key.Namespace == "" {
-		key.Namespace = src.GetNamespace()
-	}
-
-	computeBackendService, err := resolveResourceName(ctx, reader, key, schema.GroupVersionKind{
-		Group:   "compute.cnrm.cloud.google.com",
-		Version: "v1beta1",
-		Kind:    "ComputeBackendService",
-	})
-	if err != nil {
-		return nil, err
-	}
-
-	// targetField: self_link
-	// See compute servicemappings for details
-	selfLink, _, err := unstructured.NestedString(computeBackendService.Object, "status", "selfLink")
-	if err != nil || selfLink == "" {
-		return nil, fmt.Errorf("cannot get selfLink for referenced %s %v (status.selfLink is empty)", computeBackendService.GetKind(), computeBackendService.GetNamespace())
-	}
-	return &refs.ComputeBackendServiceRef{
-		External: selfLink}, nil
-}
-
 func ResolveComputeServiceAttachment(ctx context.Context, reader client.Reader, src client.Object, ref *refs.ComputeServiceAttachmentRef) (*refs.ComputeServiceAttachmentRef, error) {
 	if ref == nil {
 		return nil, nil
@@ -557,13 +514,8 @@ func resolveDependencies(ctx context.Context, reader client.Reader, obj *krm.Com
 	}
 
 	// Get backend service
-	if obj.Spec.BackendServiceRef != nil {
-		backendServiceRef, err := ResolveComputeBackendService(ctx, reader, obj, obj.Spec.BackendServiceRef)
-		if err != nil {
-			return err
-
-		}
-		obj.Spec.BackendServiceRef.External = backendServiceRef.External
+	if err := resolveBackendService(ctx, reader, obj); err != nil {
+		return err
 	}
 
 	// Get ip address, ip address is optional

pkg/controller/direct/compute/targettcpproxy/mapper.go

@@ -15,21 +15,20 @@
 package targettcpproxy
 
 import (
-	refs "github.com/GoogleCloudPlatform/k8s-config-connector/apis/refs/v1beta1"
-
+	krm "github.com/GoogleCloudPlatform/k8s-config-connector/apis/compute/v1beta1"
 	"github.com/GoogleCloudPlatform/k8s-config-connector/pkg/controller/direct"
 )
 
-func ComputeTargetTCPProxySpec_BackendServiceRef_FromProto(mapCtx *direct.MapContext, in string) *refs.ComputeBackendServiceRef {
+func ComputeTargetTCPProxySpec_BackendServiceRef_FromProto(mapCtx *direct.MapContext, in string) *krm.ComputeBackendServiceRef {
 	if in == "" {
 		return nil
 	}
-	return &refs.ComputeBackendServiceRef{
+	return &krm.ComputeBackendServiceRef{
 		External: in,
 	}
 }
 
-func ComputeTargetTCPProxySpec_BackendServiceRef_ToProto(mapCtx *direct.MapContext, in *refs.ComputeBackendServiceRef) *string {
+func ComputeTargetTCPProxySpec_BackendServiceRef_ToProto(mapCtx *direct.MapContext, in *krm.ComputeBackendServiceRef) *string {
 	if in == nil {
 		return nil
 	}