grpc: Add endpoints in resolverWrapper.NewAddress (#8149) (#8151)

Author: arjan-bal

Diff for: resolver_test.go

@@ -143,6 +143,58 @@ func (s) TestResolverAddressesToEndpoints(t *testing.T) {
 	}
 }
 
+// Test ensures one Endpoint is created for each entry in
+// resolver.State.Addresses automatically. The test calls the deprecated
+// NewAddresses API to send a list of addresses to the channel.
+func (s) TestResolverAddressesToEndpointsUsingNewAddresses(t *testing.T) {
+	ctx, cancel := context.WithTimeout(context.Background(), defaultTestTimeout)
+	defer cancel()
+
+	const scheme = "testresolveraddressestoendpoints"
+	r := manual.NewBuilderWithScheme(scheme)
+
+	stateCh := make(chan balancer.ClientConnState, 1)
+	bf := stub.BalancerFuncs{
+		UpdateClientConnState: func(_ *stub.BalancerData, ccs balancer.ClientConnState) error {
+			stateCh <- ccs
+			return nil
+		},
+	}
+	balancerName := "stub-balancer-" + scheme
+	stub.Register(balancerName, bf)
+
+	a1 := attributes.New("x", "y")
+	a2 := attributes.New("a", "b")
+	addrs := []resolver.Address{
+		{Addr: "addr1", BalancerAttributes: a1},
+		{Addr: "addr2", BalancerAttributes: a2},
+	}
+
+	cc, err := NewClient(r.Scheme()+":///",
+		WithTransportCredentials(insecure.NewCredentials()),
+		WithResolvers(r),
+		WithDefaultServiceConfig(fmt.Sprintf(`{"loadBalancingConfig": [{"%s":{}}]}`, balancerName)))
+	if err != nil {
+		t.Fatalf("grpc.NewClient() failed: %v", err)
+	}
+	cc.Connect()
+	defer cc.Close()
+	r.CC.NewAddress(addrs)
+
+	select {
+	case got := <-stateCh:
+		want := []resolver.Endpoint{
+			{Addresses: []resolver.Address{{Addr: "addr1"}}, Attributes: a1},
+			{Addresses: []resolver.Address{{Addr: "addr2"}}, Attributes: a2},
+		}
+		if diff := cmp.Diff(got.ResolverState.Endpoints, want); diff != "" {
+			t.Errorf("Did not receive expected endpoints.  Diff (-got +want):\n%v", diff)
+		}
+	case <-ctx.Done():
+		t.Fatalf("timed out waiting for endpoints")
+	}
+}
+
 // Test ensures that there is no panic if the attributes within
 // resolver.State.Addresses contains a typed-nil value.
 func (s) TestResolverAddressesWithTypedNilAttribute(t *testing.T) {

Diff for: resolver_wrapper.go

@@ -134,12 +134,7 @@ func (ccr *ccResolverWrapper) UpdateState(s resolver.State) error {
 		return nil
 	}
 	if s.Endpoints == nil {
-		s.Endpoints = make([]resolver.Endpoint, 0, len(s.Addresses))
-		for _, a := range s.Addresses {
-			ep := resolver.Endpoint{Addresses: []resolver.Address{a}, Attributes: a.BalancerAttributes}
-			ep.Addresses[0].BalancerAttributes = nil
-			s.Endpoints = append(s.Endpoints, ep)
-		}
+		s.Endpoints = addressesToEndpoints(s.Addresses)
 	}
 	ccr.addChannelzTraceEvent(s)
 	ccr.curState = s
@@ -172,7 +167,11 @@ func (ccr *ccResolverWrapper) NewAddress(addrs []resolver.Address) {
 		ccr.cc.mu.Unlock()
 		return
 	}
-	s := resolver.State{Addresses: addrs, ServiceConfig: ccr.curState.ServiceConfig}
+	s := resolver.State{
+		Addresses:     addrs,
+		ServiceConfig: ccr.curState.ServiceConfig,
+		Endpoints:     addressesToEndpoints(addrs),
+	}
 	ccr.addChannelzTraceEvent(s)
 	ccr.curState = s
 	ccr.mu.Unlock()
@@ -210,3 +209,13 @@ func (ccr *ccResolverWrapper) addChannelzTraceEvent(s resolver.State) {
 	}
 	channelz.Infof(logger, ccr.cc.channelz, "Resolver state updated: %s (%v)", pretty.ToJSON(s), strings.Join(updates, "; "))
 }
+
+func addressesToEndpoints(addrs []resolver.Address) []resolver.Endpoint {
+	endpoints := make([]resolver.Endpoint, 0, len(addrs))
+	for _, a := range addrs {
+		ep := resolver.Endpoint{Addresses: []resolver.Address{a}, Attributes: a.BalancerAttributes}
+		ep.Addresses[0].BalancerAttributes = nil
+		endpoints = append(endpoints, ep)
+	}
+	return endpoints
+}

Diff for: scripts/vet.sh

@@ -174,6 +174,7 @@ CredsBundle is deprecated:
 GetMetadata is deprecated:
 internal.Logger is deprecated:
 Metadata is deprecated: use Attributes instead.
+NewAddress is deprecated:
 NewSubConn is deprecated:
 OverrideServerName is deprecated:
 RemoveSubConn is deprecated: