snapshot of https://github.com/grpc/grpc-go.git (master, 2026-09-15; blobs > 131072B omitted)

internal/xds/xdsclient/xdsresource/tests/unmarshal_cds_test.go

@@ -0,0 +1,575 @@
+/*
+ *
+ * Copyright 2023 gRPC authors.
+ *
+ * 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 tests_test contains test cases for unmarshalling of CDS resources.
+package tests_test
+
+import (
+	"encoding/json"
+	"testing"
+
+	"github.com/google/go-cmp/cmp"
+	"github.com/google/go-cmp/cmp/cmpopts"
+	"google.golang.org/grpc/balancer/leastrequest"
+	"google.golang.org/grpc/internal/balancer/stub"
+	"google.golang.org/grpc/internal/grpctest"
+	iringhash "google.golang.org/grpc/internal/ringhash"
+	iserviceconfig "google.golang.org/grpc/internal/serviceconfig"
+	"google.golang.org/grpc/internal/testutils"
+	"google.golang.org/grpc/internal/testutils/xds/e2e"
+	xdsinternal "google.golang.org/grpc/internal/xds"
+	"google.golang.org/grpc/internal/xds/balancer/wrrlocality"
+	"google.golang.org/grpc/internal/xds/bootstrap"
+	"google.golang.org/grpc/internal/xds/xdsclient/xdsresource"
+	"google.golang.org/grpc/serviceconfig"
+	"google.golang.org/protobuf/proto"
+	"google.golang.org/protobuf/types/known/anypb"
+	"google.golang.org/protobuf/types/known/structpb"
+	"google.golang.org/protobuf/types/known/wrapperspb"
+
+	v3xdsxdstypepb "github.com/cncf/xds/go/xds/type/v3"
+	v3clusterpb "github.com/envoyproxy/go-control-plane/envoy/config/cluster/v3"
+	v3corepb "github.com/envoyproxy/go-control-plane/envoy/config/core/v3"
+	v3endpointpb "github.com/envoyproxy/go-control-plane/envoy/config/endpoint/v3"
+	v3aggregateclusterpb "github.com/envoyproxy/go-control-plane/envoy/extensions/clusters/aggregate/v3"
+	v3ringhashpb "github.com/envoyproxy/go-control-plane/envoy/extensions/load_balancing_policies/ring_hash/v3"
+	v3roundrobinpb "github.com/envoyproxy/go-control-plane/envoy/extensions/load_balancing_policies/round_robin/v3"
+	v3wrrlocalitypb "github.com/envoyproxy/go-control-plane/envoy/extensions/load_balancing_policies/wrr_locality/v3"
+
+	_ "google.golang.org/grpc/balancer/roundrobin" // To register round_robin load balancer.
+	_ "google.golang.org/grpc/xds"                 // Register the xDS LB Registry Converters.
+)
+
+type s struct {
+	grpctest.Tester
+}
+
+func Test(t *testing.T) {
+	grpctest.RunSubTests(t, s{})
+}
+
+const (
+	clusterName = "clusterName"
+	serviceName = "service"
+)
+
+func wrrLocality(t *testing.T, m proto.Message) *v3wrrlocalitypb.WrrLocality {
+	return &v3wrrlocalitypb.WrrLocality{
+		EndpointPickingPolicy: &v3clusterpb.LoadBalancingPolicy{
+			Policies: []*v3clusterpb.LoadBalancingPolicy_Policy{
+				{
+					TypedExtensionConfig: &v3corepb.TypedExtensionConfig{
+						TypedConfig: testutils.MarshalAny(t, m),
+					},
+				},
+			},
+		},
+	}
+}
+
+func wrrLocalityAny(t *testing.T, m proto.Message) *anypb.Any {
+	return testutils.MarshalAny(t, wrrLocality(t, m))
+}
+
+type customLBConfig struct {
+	serviceconfig.LoadBalancingConfig
+}
+
+// We have this test in a separate test package in order to not take a
+// dependency on the internal xDS balancer packages within the xDS Client.
+func (s) TestValidateCluster_Success(t *testing.T) {
+	const customLBPolicyName = "myorg.MyCustomLeastRequestPolicy"
+	stub.Register(customLBPolicyName, stub.BalancerFuncs{
+		ParseConfig: func(json.RawMessage) (serviceconfig.LoadBalancingConfig, error) {
+			return customLBConfig{}, nil
+		},
+	})
+	serverCfg, err := bootstrap.ServerConfigForTesting(bootstrap.ServerConfigTestingOptions{URI: "test-server"})
+	if err != nil {
+		t.Fatalf("Failed to create server config for testing: %v", err)
+	}
+
+	tests := []struct {
+		name         string
+		cluster      *v3clusterpb.Cluster
+		serverCfg    *bootstrap.ServerConfig
+		wantUpdate   xdsresource.ClusterUpdate
+		wantLBConfig *iserviceconfig.BalancerConfig
+	}{
+		{
+			name: "happy-case-logical-dns",
+			cluster: &v3clusterpb.Cluster{
+				Name:                 clusterName,
+				ClusterDiscoveryType: &v3clusterpb.Cluster_Type{Type: v3clusterpb.Cluster_LOGICAL_DNS},
+				LbPolicy:             v3clusterpb.Cluster_ROUND_ROBIN,
+				LoadAssignment: &v3endpointpb.ClusterLoadAssignment{
+					Endpoints: []*v3endpointpb.LocalityLbEndpoints{{
+						LbEndpoints: []*v3endpointpb.LbEndpoint{{
+							HostIdentifier: &v3endpointpb.LbEndpoint_Endpoint{
+								Endpoint: &v3endpointpb.Endpoint{
+									Address: &v3corepb.Address{
+										Address: &v3corepb.Address_SocketAddress{
+											SocketAddress: &v3corepb.SocketAddress{
+												Address: "dns_host",
+												PortSpecifier: &v3corepb.SocketAddress_PortValue{
+													PortValue: 8080,
+												},
+											},
+										},
+									},
+								},
+							},
+						}},
+					}},
+				},
+			},
+			wantUpdate: xdsresource.ClusterUpdate{
+				ClusterName:     clusterName,
+				ClusterType:     xdsresource.ClusterTypeLogicalDNS,
+				DNSHostName:     "dns_host:8080",
+				TelemetryLabels: xdsinternal.UnknownCSMLabels,
+			},
+			wantLBConfig: &iserviceconfig.BalancerConfig{
+				Name: wrrlocality.Name,
+				Config: &wrrlocality.LBConfig{
+					ChildPolicy: &iserviceconfig.BalancerConfig{
+						Name: "round_robin",
+					},
+				},
+			},
+		},
+		{
+			name: "happy-case-aggregate-v3",
+			cluster: &v3clusterpb.Cluster{
+				Name: clusterName,
+				ClusterDiscoveryType: &v3clusterpb.Cluster_ClusterType{
+					ClusterType: &v3clusterpb.Cluster_CustomClusterType{
+						Name: "envoy.clusters.aggregate",
+						TypedConfig: testutils.MarshalAny(t, &v3aggregateclusterpb.ClusterConfig{
+							Clusters: []string{"a", "b", "c"},
+						}),
+					},
+				},
+				LbPolicy: v3clusterpb.Cluster_ROUND_ROBIN,
+			},
+			wantUpdate: xdsresource.ClusterUpdate{
+				ClusterName:             clusterName,
+				ClusterType:             xdsresource.ClusterTypeAggregate,
+				PrioritizedClusterNames: []string{"a", "b", "c"},
+				TelemetryLabels:         xdsinternal.UnknownCSMLabels,
+			},
+			wantLBConfig: &iserviceconfig.BalancerConfig{
+				Name: wrrlocality.Name,
+				Config: &wrrlocality.LBConfig{
+					ChildPolicy: &iserviceconfig.BalancerConfig{
+						Name: "round_robin",
+					},
+				},
+			},
+		},
+		{
+			name:    "happy-case-no-service-name-no-lrs",
+			cluster: e2e.DefaultCluster(clusterName, "", e2e.SecurityLevelNone),
+			wantUpdate: xdsresource.ClusterUpdate{
+				ClusterName:     clusterName,
+				TelemetryLabels: xdsinternal.UnknownCSMLabels,
+			},
+			wantLBConfig: &iserviceconfig.BalancerConfig{
+				Name: wrrlocality.Name,
+				Config: &wrrlocality.LBConfig{
+					ChildPolicy: &iserviceconfig.BalancerConfig{
+						Name: "round_robin",
+					},
+				},
+			},
+		},
+		{
+			name:    "happy-case-no-lrs",
+			cluster: e2e.DefaultCluster(clusterName, serviceName, e2e.SecurityLevelNone),
+			wantUpdate: xdsresource.ClusterUpdate{
+				ClusterName:     clusterName,
+				EDSServiceName:  serviceName,
+				TelemetryLabels: xdsinternal.UnknownCSMLabels,
+			},
+			wantLBConfig: &iserviceconfig.BalancerConfig{
+				Name: wrrlocality.Name,
+				Config: &wrrlocality.LBConfig{
+					ChildPolicy: &iserviceconfig.BalancerConfig{
+						Name: "round_robin",
+					},
+				},
+			},
+		},
+		{
+			name: "happiest-case-with-lrs",
+			cluster: e2e.ClusterResourceWithOptions(e2e.ClusterOptions{
+				ClusterName: clusterName,
+				ServiceName: serviceName,
+				EnableLRS:   true,
+			}),
+			serverCfg: serverCfg,
+			wantUpdate: xdsresource.ClusterUpdate{
+				ClusterName:     clusterName,
+				EDSServiceName:  serviceName,
+				LRSServerConfig: serverCfg,
+				TelemetryLabels: xdsinternal.UnknownCSMLabels,
+			},
+			wantLBConfig: &iserviceconfig.BalancerConfig{
+				Name: wrrlocality.Name,
+				Config: &wrrlocality.LBConfig{
+					ChildPolicy: &iserviceconfig.BalancerConfig{
+						Name: "round_robin",
+					},
+				},
+			},
+		},
+		{
+			name: "happiest-case-with-circuitbreakers",
+			cluster: func() *v3clusterpb.Cluster {
+				c := e2e.ClusterResourceWithOptions(e2e.ClusterOptions{
+					ClusterName: clusterName,
+					ServiceName: serviceName,
+					EnableLRS:   true,
+				})
+				c.CircuitBreakers = &v3clusterpb.CircuitBreakers{
+					Thresholds: []*v3clusterpb.CircuitBreakers_Thresholds{
+						{
+							Priority:    v3corepb.RoutingPriority_DEFAULT,
+							MaxRequests: wrapperspb.UInt32(512),
+						},
+						{
+							Priority:    v3corepb.RoutingPriority_HIGH,
+							MaxRequests: nil,
+						},
+					},
+				}
+				return c
+			}(),
+			serverCfg: serverCfg,
+			wantUpdate: xdsresource.ClusterUpdate{
+				ClusterName:     clusterName,
+				EDSServiceName:  serviceName,
+				LRSServerConfig: serverCfg,
+				MaxRequests:     func() *uint32 { i := uint32(512); return &i }(),
+				TelemetryLabels: xdsinternal.UnknownCSMLabels,
+			},
+			wantLBConfig: &iserviceconfig.BalancerConfig{
+				Name: wrrlocality.Name,
+				Config: &wrrlocality.LBConfig{
+					ChildPolicy: &iserviceconfig.BalancerConfig{
+						Name: "round_robin",
+					},
+				},
+			},
+		},
+		{
+			name: "happiest-case-with-ring-hash-lb-policy-with-default-config",
+			cluster: func() *v3clusterpb.Cluster {
+				c := e2e.DefaultCluster(clusterName, serviceName, e2e.SecurityLevelNone)
+				c.LbPolicy = v3clusterpb.Cluster_RING_HASH
+				return c
+			}(),
+			wantUpdate: xdsresource.ClusterUpdate{
+				ClusterName:     clusterName,
+				EDSServiceName:  serviceName,
+				TelemetryLabels: xdsinternal.UnknownCSMLabels,
+			},
+			wantLBConfig: &iserviceconfig.BalancerConfig{
+				Name: "ring_hash_experimental",
+				Config: &iringhash.LBConfig{
+					MinRingSize: 1024,
+					MaxRingSize: 4096,
+				},
+			},
+		},
+		{
+			name: "happiest-case-with-least-request-lb-policy-with-default-config",
+			cluster: &v3clusterpb.Cluster{
+				Name:                 clusterName,
+				ClusterDiscoveryType: &v3clusterpb.Cluster_Type{Type: v3clusterpb.Cluster_EDS},
+				EdsClusterConfig: &v3clusterpb.Cluster_EdsClusterConfig{
+					EdsConfig: &v3corepb.ConfigSource{
+						ConfigSourceSpecifier: &v3corepb.ConfigSource_Ads{
+							Ads: &v3corepb.AggregatedConfigSource{},
+						},
+					},
+					ServiceName: serviceName,
+				},
+				LbPolicy: v3clusterpb.Cluster_LEAST_REQUEST,
+			},
+			wantUpdate: xdsresource.ClusterUpdate{
+				ClusterName:     clusterName,
+				EDSServiceName:  serviceName,
+				TelemetryLabels: xdsinternal.UnknownCSMLabels,
+			},
+			wantLBConfig: &iserviceconfig.BalancerConfig{
+				Name: "least_request_experimental",
+				Config: &leastrequest.LBConfig{
+					ChoiceCount: 2,
+				},
+			},
+		},
+		{
+			name: "happiest-case-with-ring-hash-lb-policy-with-none-default-config",
+			cluster: func() *v3clusterpb.Cluster {
+				c := e2e.DefaultCluster(clusterName, serviceName, e2e.SecurityLevelNone)
+				c.LbPolicy = v3clusterpb.Cluster_RING_HASH
+				c.LbConfig = &v3clusterpb.Cluster_RingHashLbConfig_{
+					RingHashLbConfig: &v3clusterpb.Cluster_RingHashLbConfig{
+						MinimumRingSize: wrapperspb.UInt64(10),
+						MaximumRingSize: wrapperspb.UInt64(100),
+					},
+				}
+				return c
+			}(),
+			wantUpdate: xdsresource.ClusterUpdate{
+				ClusterName:     clusterName,
+				EDSServiceName:  serviceName,
+				TelemetryLabels: xdsinternal.UnknownCSMLabels,
+			},
+			wantLBConfig: &iserviceconfig.BalancerConfig{
+				Name: "ring_hash_experimental",
+				Config: &iringhash.LBConfig{
+					MinRingSize: 10,
+					MaxRingSize: 100,
+				},
+			},
+		},
+		{
+			name: "happiest-case-with-least-request-lb-policy-with-none-default-config",
+			cluster: &v3clusterpb.Cluster{
+				Name:                 clusterName,
+				ClusterDiscoveryType: &v3clusterpb.Cluster_Type{Type: v3clusterpb.Cluster_EDS},
+				EdsClusterConfig: &v3clusterpb.Cluster_EdsClusterConfig{
+					EdsConfig: &v3corepb.ConfigSource{
+						ConfigSourceSpecifier: &v3corepb.ConfigSource_Ads{
+							Ads: &v3corepb.AggregatedConfigSource{},
+						},
+					},
+					ServiceName: serviceName,
+				},
+				LbPolicy: v3clusterpb.Cluster_LEAST_REQUEST,
+				LbConfig: &v3clusterpb.Cluster_LeastRequestLbConfig_{
+					LeastRequestLbConfig: &v3clusterpb.Cluster_LeastRequestLbConfig{
+						ChoiceCount: wrapperspb.UInt32(3),
+					},
+				},
+			},
+			wantUpdate: xdsresource.ClusterUpdate{
+				ClusterName:     clusterName,
+				EDSServiceName:  serviceName,
+				TelemetryLabels: xdsinternal.UnknownCSMLabels,
+			},
+			wantLBConfig: &iserviceconfig.BalancerConfig{
+				Name: "least_request_experimental",
+				Config: &leastrequest.LBConfig{
+					ChoiceCount: 3,
+				},
+			},
+		},
+		{
+			name: "happiest-case-with-ring-hash-lb-policy-configured-through-LoadBalancingPolicy",
+			cluster: &v3clusterpb.Cluster{
+				Name:                 clusterName,
+				ClusterDiscoveryType: &v3clusterpb.Cluster_Type{Type: v3clusterpb.Cluster_EDS},
+				EdsClusterConfig: &v3clusterpb.Cluster_EdsClusterConfig{
+					EdsConfig: &v3corepb.ConfigSource{
+						ConfigSourceSpecifier: &v3corepb.ConfigSource_Ads{
+							Ads: &v3corepb.AggregatedConfigSource{},
+						},
+					},
+					ServiceName: serviceName,
+				},
+				LoadBalancingPolicy: &v3clusterpb.LoadBalancingPolicy{
+					Policies: []*v3clusterpb.LoadBalancingPolicy_Policy{
+						{
+							TypedExtensionConfig: &v3corepb.TypedExtensionConfig{
+								TypedConfig: testutils.MarshalAny(t, &v3ringhashpb.RingHash{
+									HashFunction:    v3ringhashpb.RingHash_XX_HASH,
+									MinimumRingSize: wrapperspb.UInt64(10),
+									MaximumRingSize: wrapperspb.UInt64(100),
+								}),
+							},
+						},
+					},
+				},
+			},
+			wantUpdate: xdsresource.ClusterUpdate{
+				ClusterName:     clusterName,
+				EDSServiceName:  serviceName,
+				TelemetryLabels: xdsinternal.UnknownCSMLabels,
+			},
+			wantLBConfig: &iserviceconfig.BalancerConfig{
+				Name: "ring_hash_experimental",
+				Config: &iringhash.LBConfig{
+					MinRingSize: 10,
+					MaxRingSize: 100,
+				},
+			},
+		},
+		{
+			name: "happiest-case-with-wrrlocality-rr-child-configured-through-LoadBalancingPolicy",
+			cluster: &v3clusterpb.Cluster{
+				Name:                 clusterName,
+				ClusterDiscoveryType: &v3clusterpb.Cluster_Type{Type: v3clusterpb.Cluster_EDS},
+				EdsClusterConfig: &v3clusterpb.Cluster_EdsClusterConfig{
+					EdsConfig: &v3corepb.ConfigSource{
+						ConfigSourceSpecifier: &v3corepb.ConfigSource_Ads{
+							Ads: &v3corepb.AggregatedConfigSource{},
+						},
+					},
+					ServiceName: serviceName,
+				},
+				LoadBalancingPolicy: &v3clusterpb.LoadBalancingPolicy{
+					Policies: []*v3clusterpb.LoadBalancingPolicy_Policy{
+						{
+							TypedExtensionConfig: &v3corepb.TypedExtensionConfig{
+								TypedConfig: wrrLocalityAny(t, &v3roundrobinpb.RoundRobin{}),
+							},
+						},
+					},
+				},
+			},
+			wantUpdate: xdsresource.ClusterUpdate{
+				ClusterName:     clusterName,
+				EDSServiceName:  serviceName,
+				TelemetryLabels: xdsinternal.UnknownCSMLabels,
+			},
+			wantLBConfig: &iserviceconfig.BalancerConfig{
+				Name: wrrlocality.Name,
+				Config: &wrrlocality.LBConfig{
+					ChildPolicy: &iserviceconfig.BalancerConfig{
+						Name: "round_robin",
+					},
+				},
+			},
+		},
+		{
+			name: "happiest-case-with-custom-lb-configured-through-LoadBalancingPolicy",
+			cluster: &v3clusterpb.Cluster{
+				Name:                 clusterName,
+				ClusterDiscoveryType: &v3clusterpb.Cluster_Type{Type: v3clusterpb.Cluster_EDS},
+				EdsClusterConfig: &v3clusterpb.Cluster_EdsClusterConfig{
+					EdsConfig: &v3corepb.ConfigSource{
+						ConfigSourceSpecifier: &v3corepb.ConfigSource_Ads{
+							Ads: &v3corepb.AggregatedConfigSource{},
+						},
+					},
+					ServiceName: serviceName,
+				},
+				LoadBalancingPolicy: &v3clusterpb.LoadBalancingPolicy{
+					Policies: []*v3clusterpb.LoadBalancingPolicy_Policy{
+						{
+							TypedExtensionConfig: &v3corepb.TypedExtensionConfig{
+								TypedConfig: wrrLocalityAny(t, &v3xdsxdstypepb.TypedStruct{
+									TypeUrl: "type.googleapis.com/myorg.MyCustomLeastRequestPolicy",
+									Value:   &structpb.Struct{},
+								}),
+							},
+						},
+					},
+				},
+			},
+			wantUpdate: xdsresource.ClusterUpdate{
+				ClusterName:     clusterName,
+				EDSServiceName:  serviceName,
+				TelemetryLabels: xdsinternal.UnknownCSMLabels,
+			},
+			wantLBConfig: &iserviceconfig.BalancerConfig{
+				Name: wrrlocality.Name,
+				Config: &wrrlocality.LBConfig{
+					ChildPolicy: &iserviceconfig.BalancerConfig{
+						Name:   "myorg.MyCustomLeastRequestPolicy",
+						Config: customLBConfig{},
+					},
+				},
+			},
+		},
+		{
+			name: "load-balancing-policy-takes-precedence-over-lb-policy-and-enum",
+			cluster: &v3clusterpb.Cluster{
+				Name:                 clusterName,
+				ClusterDiscoveryType: &v3clusterpb.Cluster_Type{Type: v3clusterpb.Cluster_EDS},
+				EdsClusterConfig: &v3clusterpb.Cluster_EdsClusterConfig{
+					EdsConfig: &v3corepb.ConfigSource{
+						ConfigSourceSpecifier: &v3corepb.ConfigSource_Ads{
+							Ads: &v3corepb.AggregatedConfigSource{},
+						},
+					},
+					ServiceName: serviceName,
+				},
+				LbPolicy: v3clusterpb.Cluster_RING_HASH,
+				LbConfig: &v3clusterpb.Cluster_RingHashLbConfig_{
+					RingHashLbConfig: &v3clusterpb.Cluster_RingHashLbConfig{
+						MinimumRingSize: wrapperspb.UInt64(20),
+						MaximumRingSize: wrapperspb.UInt64(200),
+					},
+				},
+				LoadBalancingPolicy: &v3clusterpb.LoadBalancingPolicy{
+					Policies: []*v3clusterpb.LoadBalancingPolicy_Policy{
+						{
+							TypedExtensionConfig: &v3corepb.TypedExtensionConfig{
+								TypedConfig: testutils.MarshalAny(t, &v3ringhashpb.RingHash{
+									HashFunction:    v3ringhashpb.RingHash_XX_HASH,
+									MinimumRingSize: wrapperspb.UInt64(10),
+									MaximumRingSize: wrapperspb.UInt64(100),
+								}),
+							},
+						},
+					},
+				},
+			},
+			wantUpdate: xdsresource.ClusterUpdate{
+				ClusterName:     clusterName,
+				EDSServiceName:  serviceName,
+				TelemetryLabels: xdsinternal.UnknownCSMLabels,
+			},
+			wantLBConfig: &iserviceconfig.BalancerConfig{
+				Name: "ring_hash_experimental",
+				Config: &iringhash.LBConfig{
+					MinRingSize: 10,
+					MaxRingSize: 100,
+				},
+			},
+		},
+	}
+
+	for _, test := range tests {
+		t.Run(test.name, func(t *testing.T) {
+			update, err := xdsresource.ValidateClusterAndConstructClusterUpdateForTesting(test.cluster, test.serverCfg)
+			if err != nil {
+				t.Errorf("validateClusterAndConstructClusterUpdate(%+v) failed: %v", test.cluster, err)
+			}
+			// Ignore the raw JSON string into the cluster update. JSON bytes
+			// are nondeterministic (whitespace etc.) so we cannot reliably
+			// compare JSON bytes in a test. Thus, marshal into a Balancer
+			// Config struct and compare on that. Only need to test this JSON
+			// emission here, as this covers the possible output space.
+			if diff := cmp.Diff(update, test.wantUpdate, cmpopts.EquateEmpty(), cmpopts.IgnoreFields(xdsresource.ClusterUpdate{}, "LBPolicy")); diff != "" {
+				t.Errorf("validateClusterAndConstructClusterUpdate(%+v) got diff: %v (-got, +want)", test.cluster, diff)
+			}
+			bc := &iserviceconfig.BalancerConfig{}
+			if err := json.Unmarshal(update.LBPolicy, bc); err != nil {
+				t.Fatalf("failed to unmarshal JSON: %v", err)
+			}
+			if diff := cmp.Diff(bc, test.wantLBConfig); diff != "" {
+				t.Fatalf("update.LBConfig got unexpected output, diff (-got +want): %v", diff)
+			}
+		})
+	}
+}