add common computeEtag function

apis/cloudbuild/v1alpha1/workerpool_types.go

@@ -87,7 +87,9 @@ type CloudBuildWorkerPoolObservedState struct {
 	WorkerConfig  *WorkerConfig       `json:"workerConfig,omitempty"`
 	NetworkConfig *NetworkConfigState `json:"networkConfig,omitempty"`
 
-	ETag *string `json:"eTag,omitempty"`
+	/* The Checksum computed by the server, using weak indicator.*/
+	// +optional
+	ETag *string `json:"etag,omitempty"`
 }
 
 type NetworkConfigState struct {

config/crds/resources/apiextensions.k8s.io_v1_customresourcedefinition_cloudbuildworkerpools.cloudbuild.cnrm.cloud.google.com.yaml

@@ -180,7 +180,8 @@ spec:
                     description: The creation timestamp of the workerpool.
                     format: date-time
                     type: string
-                  eTag:
+                  etag:
+                    description: The Checksum computed by the server, using weak indicator.
                     type: string
                   networkConfig:
                     properties:

mockgcp/common/fields/etag.go

@@ -0,0 +1,71 @@
+// 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 fields
+
+import (
+	"crypto/sha256"
+	"encoding/base64"
+	"fmt"
+
+	"google.golang.org/protobuf/encoding/prototext"
+	"google.golang.org/protobuf/proto"
+)
+
+var mustFields = []string{
+	"displayName",
+	"state",
+}
+
+// ComputeEtag computes the etag of the proto object with weak indicator.
+func ComputeEtag(obj proto.Message) string {
+	pb := proto.Clone(obj)
+
+	// ignore dynamic fields like timestampe or uniqueId.
+	descriptor := pb.ProtoReflect().Descriptor()
+	fieldDescs := descriptor.Fields()
+	for i := 0; i < fieldDescs.Len(); i++ {
+		fieldDesc := fieldDescs.Get(i)
+		must := false
+		for _, mustField := range mustFields {
+			if fieldDesc.JSONName() == mustField {
+				must = true
+			}
+		}
+		if !must {
+			pb.ProtoReflect().Clear(fieldDesc)
+		}
+	}
+
+	m, err := prototext.Marshal(pb)
+	if err != nil {
+		panic(fmt.Sprintf("converting to prototext: %v", err))
+	}
+	h := sha256.Sum256([]byte(m))
+	str := base64.StdEncoding.EncodeToString(h[:])
+	strong := fmt.Sprintf(`"%s"`, str) // ETag must be quoted.
+	return "W/" + strong
+}
+
+func ComputeEtagBytes(obj proto.Message) []byte {
+	return []byte(ComputeEtag(obj))
+}
+
+func ComputeEtagPtr(obj proto.Message) *string {
+	return ptrTo(ComputeEtag(obj))
+}
+
+func ptrTo[T any](t T) *T {
+	return &t
+}

mockgcp/mockcloudbuild/workerpool.go

@@ -20,6 +20,7 @@ import (
 	"strings"
 
 	"cloud.google.com/go/longrunning/autogen/longrunningpb"
+	"github.com/GoogleCloudPlatform/k8s-config-connector/mockgcp/common/fields"
 	"github.com/GoogleCloudPlatform/k8s-config-connector/mockgcp/common/projects"
 	pb "github.com/GoogleCloudPlatform/k8s-config-connector/mockgcp/generated/mockgcp/devtools/cloudbuild/v1"
 	"google.golang.org/grpc/codes"
@@ -77,7 +78,7 @@ func (s *CloudBuildV1) CreateWorkerPool(ctx context.Context, req *pb.CreateWorke
 		result.CreateTime = now
 		result.UpdateTime = now
 		result.State = pb.WorkerPool_RUNNING
-		result.Etag = "W/11111111111111111111111111111111"
+		result.Etag = fields.ComputeEtag(result)
 		return result, nil
 	})
 }
@@ -123,7 +124,7 @@ func (s *CloudBuildV1) UpdateWorkerPool(ctx context.Context, req *pb.UpdateWorke
 		result := proto.Clone(obj).(*pb.WorkerPool)
 		result.UpdateTime = now
 		result.State = pb.WorkerPool_RUNNING
-		result.Etag = "W/22222222222222222222222222222222"
+		result.Etag = fields.ComputeEtag(result)
 		return result, nil
 	})
 }

pkg/test/resourcefixture/testdata/basic/cloudbuild/v1alpha1/cloudbuildworkerpool/_generated_object_cloudbuildworkerpool.golden.yaml

@@ -33,7 +33,7 @@ status:
   observedGeneration: 2
   observedState:
     createTime: "1970-01-01T00:00:00Z"
-    eTag: W/22222222222222222222222222222222
+    etag: W/"pwzCjvRptOAz64ZilGUmgNZjYVh0LzD3Oh+zEbMPULw="
     networkConfig:
       egressOption: NO_PUBLIC_EGRESS
       peeredNetwork: projects/${projectId}/global/networks/computenetwork-${uniqueId}