From d31dbe7ad3a45f38cd482213867b19a9378b2dee Mon Sep 17 00:00:00 2001
From: Menghan Li <menghanl@google.com>
Date: Wed, 26 Jan 2022 11:39:28 -0800
Subject: [PATCH] xds/resource: accept Self as LDS's RDS config source and
 CDS's EDS config source (#5152)

---
 .../xdsclient/xdsresource/unmarshal_cds.go    |  4 +--
 .../xdsresource/unmarshal_cds_test.go         | 32 +++++++++++++++++
 .../xdsclient/xdsresource/unmarshal_lds.go    |  4 +--
 .../xdsresource/unmarshal_lds_test.go         | 36 ++++++++++++++++++-
 4 files changed, 71 insertions(+), 5 deletions(-)

diff --git a/xds/internal/xdsclient/xdsresource/unmarshal_cds.go b/xds/internal/xdsclient/xdsresource/unmarshal_cds.go
index 2b8d8d3aadd..8501e9e100e 100644
--- a/xds/internal/xdsclient/xdsresource/unmarshal_cds.go
+++ b/xds/internal/xdsclient/xdsresource/unmarshal_cds.go
@@ -145,8 +145,8 @@ func validateClusterAndConstructClusterUpdate(cluster *v3clusterpb.Cluster) (Clu
 	// Validate and set cluster type from the response.
 	switch {
 	case cluster.GetType() == v3clusterpb.Cluster_EDS:
-		if cluster.GetEdsClusterConfig().GetEdsConfig().GetAds() == nil {
-			return ClusterUpdate{}, fmt.Errorf("unexpected edsConfig in response: %+v", cluster)
+		if configsource := cluster.GetEdsClusterConfig().GetEdsConfig(); configsource.GetAds() == nil && configsource.GetSelf() == nil {
+			return ClusterUpdate{}, fmt.Errorf("CDS's EDS config source is not ADS or Self: %+v", cluster)
 		}
 		ret.ClusterType = ClusterTypeEDS
 		ret.EDSServiceName = cluster.GetEdsClusterConfig().GetServiceName()
diff --git a/xds/internal/xdsclient/xdsresource/unmarshal_cds_test.go b/xds/internal/xdsclient/xdsresource/unmarshal_cds_test.go
index 4aad9308fc0..1a303074098 100644
--- a/xds/internal/xdsclient/xdsresource/unmarshal_cds_test.go
+++ b/xds/internal/xdsclient/xdsresource/unmarshal_cds_test.go
@@ -1421,6 +1421,23 @@ func (s) TestUnmarshalCluster(t *testing.T) {
 				},
 			},
 		})
+
+		v3ClusterAnyWithEDSConfigSourceSelf = testutils.MarshalAny(&v3clusterpb.Cluster{
+			Name:                 v3ClusterName,
+			ClusterDiscoveryType: &v3clusterpb.Cluster_Type{Type: v3clusterpb.Cluster_EDS},
+			EdsClusterConfig: &v3clusterpb.Cluster_EdsClusterConfig{
+				EdsConfig: &v3corepb.ConfigSource{
+					ConfigSourceSpecifier: &v3corepb.ConfigSource_Self{},
+				},
+				ServiceName: v3Service,
+			},
+			LbPolicy: v3clusterpb.Cluster_ROUND_ROBIN,
+			LrsServer: &v3corepb.ConfigSource{
+				ConfigSourceSpecifier: &v3corepb.ConfigSource_Self{
+					Self: &v3corepb.SelfConfigSource{},
+				},
+			},
+		})
 	)
 	const testVersion = "test-version-cds"
 
@@ -1513,6 +1530,21 @@ func (s) TestUnmarshalCluster(t *testing.T) {
 				Version: testVersion,
 			},
 		},
+		{
+			name:      "v3 cluster with EDS config source self",
+			resources: []*anypb.Any{v3ClusterAnyWithEDSConfigSourceSelf},
+			wantUpdate: map[string]ClusterUpdateErrTuple{
+				v3ClusterName: {Update: ClusterUpdate{
+					ClusterName:    v3ClusterName,
+					EDSServiceName: v3Service, EnableLRS: true,
+					Raw: v3ClusterAnyWithEDSConfigSourceSelf,
+				}},
+			},
+			wantMD: UpdateMetadata{
+				Status:  ServiceStatusACKed,
+				Version: testVersion,
+			},
+		},
 		{
 			name:      "multiple clusters",
 			resources: []*anypb.Any{v2ClusterAny, v3ClusterAny},
diff --git a/xds/internal/xdsclient/xdsresource/unmarshal_lds.go b/xds/internal/xdsclient/xdsresource/unmarshal_lds.go
index f9663d05bee..b259c7b87e4 100644
--- a/xds/internal/xdsclient/xdsresource/unmarshal_lds.go
+++ b/xds/internal/xdsclient/xdsresource/unmarshal_lds.go
@@ -102,8 +102,8 @@ func processClientSideListener(lis *v3listenerpb.Listener, logger *grpclog.Prefi
 
 	switch apiLis.RouteSpecifier.(type) {
 	case *v3httppb.HttpConnectionManager_Rds:
-		if apiLis.GetRds().GetConfigSource().GetAds() == nil {
-			return nil, fmt.Errorf("ConfigSource is not ADS: %+v", lis)
+		if configsource := apiLis.GetRds().GetConfigSource(); configsource.GetAds() == nil && configsource.GetSelf() == nil {
+			return nil, fmt.Errorf("LDS's RDS configSource is not ADS or Self: %+v", lis)
 		}
 		name := apiLis.GetRds().GetRouteConfigName()
 		if name == "" {
diff --git a/xds/internal/xdsclient/xdsresource/unmarshal_lds_test.go b/xds/internal/xdsclient/xdsresource/unmarshal_lds_test.go
index a5c53886ecb..4444421a492 100644
--- a/xds/internal/xdsclient/xdsresource/unmarshal_lds_test.go
+++ b/xds/internal/xdsclient/xdsresource/unmarshal_lds_test.go
@@ -204,6 +204,25 @@ func (s) TestUnmarshalListener_ClientSide(t *testing.T) {
 				},
 			})
 		}
+
+		v3ListenerWithCDSConfigSourceSelf = testutils.MarshalAny(&v3listenerpb.Listener{
+			Name: v3LDSTarget,
+			ApiListener: &v3listenerpb.ApiListener{
+				ApiListener: testutils.MarshalAny(
+					&v3httppb.HttpConnectionManager{
+						RouteSpecifier: &v3httppb.HttpConnectionManager_Rds{
+							Rds: &v3httppb.Rds{
+								ConfigSource: &v3corepb.ConfigSource{
+									ConfigSourceSpecifier: &v3corepb.ConfigSource_Self{},
+								},
+								RouteConfigName: v3RouteConfigName,
+							},
+						},
+						HttpFilters: []*v3httppb.HttpFilter{emptyRouterFilter},
+					}),
+			},
+		})
+
 		errMD = UpdateMetadata{
 			Status:  ServiceStatusNACKed,
 			Version: testVersion,
@@ -294,7 +313,22 @@ func (s) TestUnmarshalListener_ClientSide(t *testing.T) {
 			wantErr:    true,
 		},
 		{
-			name: "rds.ConfigSource in apiListener is not ADS",
+			name:      "rds.ConfigSource in apiListener is Self",
+			resources: []*anypb.Any{v3ListenerWithCDSConfigSourceSelf},
+			wantUpdate: map[string]ListenerUpdateErrTuple{
+				v3LDSTarget: {Update: ListenerUpdate{
+					RouteConfigName: v3RouteConfigName,
+					HTTPFilters:     []HTTPFilter{routerFilter},
+					Raw:             v3ListenerWithCDSConfigSourceSelf,
+				}},
+			},
+			wantMD: UpdateMetadata{
+				Status:  ServiceStatusACKed,
+				Version: testVersion,
+			},
+		},
+		{
+			name: "rds.ConfigSource in apiListener is not ADS or Self",
 			resources: []*anypb.Any{testutils.MarshalAny(&v3listenerpb.Listener{
 				Name: v3LDSTarget,
 				ApiListener: &v3listenerpb.ApiListener{