Add externalRef for ComputeFirewallPolicyRule

apis/compute/v1beta1/computefirewallpolicyrule_reference.go

@@ -0,0 +1,166 @@
+// Copyright 2024 Google LLC
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package v1beta1
+
+import (
+	"context"
+	"fmt"
+	"strings"
+
+	refsv1beta1 "github.com/GoogleCloudPlatform/k8s-config-connector/apis/refs/v1beta1"
+	"github.com/GoogleCloudPlatform/k8s-config-connector/pkg/k8s"
+	apierrors "k8s.io/apimachinery/pkg/api/errors"
+	"k8s.io/apimachinery/pkg/apis/meta/v1/unstructured"
+	"k8s.io/apimachinery/pkg/types"
+	"sigs.k8s.io/controller-runtime/pkg/client"
+)
+
+var _ refsv1beta1.ExternalNormalizer = &ComputeFirewallPolicyRuleRef{}
+
+// ComputeFirewallPolicyRuleRef defines the resource reference to ComputeFirewallPolicyRule, which "External" field
+// holds the GCP identifier for the KRM object.
+type ComputeFirewallPolicyRuleRef struct {
+	// A reference to an externally managed ComputeFirewallPolicyRule resource.
+	// Should be in the format "locations/global/firewallPolicies/<firewallPolicy>/rules/<priority>".
+	External string `json:"external,omitempty"`
+
+	// The name of a ComputeFirewallPolicyRule resource.
+	Name string `json:"name,omitempty"`
+
+	// The namespace of a ComputeFirewallPolicyRule resource.
+	Namespace string `json:"namespace,omitempty"`
+
+	parent *ComputeFirewallPolicyRuleParent
+}
+
+// NormalizedExternal provision the "External" value for other resource that depends on ComputeFirewallPolicyRule.
+// If the "External" is given in the other resource's spec.ComputeFirewallPolicyRuleRef, the given value will be used.
+// Otherwise, the "Name" and "Namespace" will be used to query the actual ComputeFirewallPolicyRule object from the cluster.
+func (r *ComputeFirewallPolicyRuleRef) NormalizedExternal(ctx context.Context, reader client.Reader, otherNamespace string) (string, error) {
+	if r.External != "" && r.Name != "" {
+		return "", fmt.Errorf("cannot specify both name and external on %s reference", ComputeFirewallPolicyRuleGVK.Kind)
+	}
+	// From given External
+	if r.External != "" {
+		if _, _, err := parseComputeFirewallPolicyRuleExternal(r.External); err != nil {
+			return "", err
+		}
+		return r.External, nil
+	}
+
+	// From the Config Connector object
+	if r.Namespace == "" {
+		r.Namespace = otherNamespace
+	}
+	key := types.NamespacedName{Name: r.Name, Namespace: r.Namespace}
+	u := &unstructured.Unstructured{}
+	u.SetGroupVersionKind(ComputeFirewallPolicyRuleGVK)
+	if err := reader.Get(ctx, key, u); err != nil {
+		if apierrors.IsNotFound(err) {
+			return "", k8s.NewReferenceNotFoundError(u.GroupVersionKind(), key)
+		}
+		return "", fmt.Errorf("reading referenced %s %s: %w", ComputeFirewallPolicyRuleGVK, key, err)
+	}
+	// Get external from status.externalRef. This is the most trustworthy place.
+	actualExternalRef, _, err := unstructured.NestedString(u.Object, "status", "externalRef")
+	if err != nil {
+		return "", fmt.Errorf("reading status.externalRef: %w", err)
+	}
+	if actualExternalRef == "" {
+		return "", fmt.Errorf("ComputeFirewallPolicyRule is not ready yet")
+	}
+	r.External = actualExternalRef
+	return r.External, nil
+}
+
+// New builds a NewComputeFirewallPolicyRuleRef from the Config Connector ComputeFirewallPolicyRule object.
+func NewComputeFirewallPolicyRuleRef(ctx context.Context, reader client.Reader, obj *ComputeFirewallPolicyRule) (*ComputeFirewallPolicyRuleRef, error) {
+	id := &ComputeFirewallPolicyRuleRef{}
+
+	firewallPolicyRef, err := refsv1beta1.ResolveComputeFirewallPolicy(ctx, reader, obj, obj.Spec.FirewallPolicyRef)
+	if err != nil {
+		return nil, err
+	}
+	firewallPolicy := firewallPolicyRef.External
+	if firewallPolicy == "" {
+		return nil, fmt.Errorf("cannot resolve firewallPolicy")
+	}
+
+	id.parent = &ComputeFirewallPolicyRuleParent{FirewallPolicy: firewallPolicy}
+
+	// Get priority. Priority is a required field
+	priority := fmt.Sprintf("%v", obj.Spec.Priority)
+
+	// Use approved External
+	externalRef := valueOf(obj.Status.ExternalRef)
+	if externalRef == "" {
+		id.External = asComputeFirewallPolicyRuleExternal(id.parent, priority)
+		return id, nil
+	}
+
+	// Validate desired with actual
+	actualParent, actualPriority, err := parseComputeFirewallPolicyRuleExternal(externalRef)
+	if err != nil {
+		return nil, err
+	}
+	if actualParent.FirewallPolicy != firewallPolicy {
+		return nil, fmt.Errorf("spec.firewallPolicyRef changed, expect %s, got %s", actualParent.FirewallPolicy, firewallPolicy)
+	}
+	if actualPriority != priority {
+		return nil, fmt.Errorf("cannot reset `spec.priority` to %s, since it has already assigned to %s",
+			priority, actualPriority)
+	}
+	id.External = externalRef
+	id.parent = &ComputeFirewallPolicyRuleParent{FirewallPolicy: firewallPolicy}
+	return id, nil
+}
+
+func (r *ComputeFirewallPolicyRuleRef) Parent() (*ComputeFirewallPolicyRuleParent, error) {
+	if r.parent != nil {
+		return r.parent, nil
+	}
+	if r.External != "" {
+		parent, _, err := parseComputeFirewallPolicyRuleExternal(r.External)
+		if err != nil {
+			return nil, err
+		}
+		return parent, nil
+	}
+	return nil, fmt.Errorf("ComputeFirewallPolicyRule not initialized from `NewComputeFirewallPolicyRuleRef` or `NormalizedExternal`")
+}
+
+type ComputeFirewallPolicyRuleParent struct {
+	FirewallPolicy string
+}
+
+func (p *ComputeFirewallPolicyRuleParent) String() string {
+	return "locations/global/firewallPolicies/" + p.FirewallPolicy
+}
+
+func asComputeFirewallPolicyRuleExternal(parent *ComputeFirewallPolicyRuleParent, priority string) (external string) {
+	return parent.String() + "/rules/" + priority
+}
+
+func parseComputeFirewallPolicyRuleExternal(external string) (parent *ComputeFirewallPolicyRuleParent, priority string, err error) {
+	tokens := strings.Split(external, "/")
+	if len(tokens) != 6 || tokens[0] != "locations" || tokens[2] != "firewallPolicies" || tokens[4] != "rules" {
+		return nil, "", fmt.Errorf("format of ComputeFirewallPolicyRule external=%q was not known (use firewallPolicies/<firewallPolicy>/rules/<priority>)", external)
+	}
+	parent = &ComputeFirewallPolicyRuleParent{
+		FirewallPolicy: tokens[3],
+	}
+	priority = tokens[5]
+	return parent, priority, nil
+}

apis/refs/v1beta1/computerefs.go

@@ -281,3 +281,49 @@ type ComputeFirewallPolicyRef struct {
 	/* The `namespace` field of a `ComputeFirewallPolicy ` resource. */
 	Namespace string `json:"namespace,omitempty"`
 }
+
+func ResolveComputeFirewallPolicy(ctx context.Context, reader client.Reader, src client.Object, ref *ComputeFirewallPolicyRef) (*ComputeFirewallPolicyRef, 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()
+	}
+
+	computeFirewallPolicy := &unstructured.Unstructured{}
+	computeFirewallPolicy.SetGroupVersionKind(schema.GroupVersionKind{
+		Group:   "compute.cnrm.cloud.google.com",
+		Version: "v1beta1",
+		Kind:    "ComputeFirewallPolicy",
+	})
+	if err := reader.Get(ctx, key, computeFirewallPolicy); err != nil {
+		if apierrors.IsNotFound(err) {
+			return nil, k8s.NewReferenceNotFoundError(computeFirewallPolicy.GroupVersionKind(), key)
+		}
+		return nil, fmt.Errorf("error reading referenced ComputeFirewallPolicy %v: %w", key, err)
+	}
+
+	resourceID, err := GetResourceID(computeFirewallPolicy)
+	if err != nil {
+		return nil, err
+	}
+
+	return &ComputeFirewallPolicyRef{
+		External: fmt.Sprintf("%s", resourceID)}, nil
+}