Method TestWeightedTarget_NoTargets

balancer/weightedtarget/weightedtarget_test.go:177–205

Tests the behavior of the weighted_target LB policy when there are no targets configured. It verifies that the LB policy sets the overall channel state to TRANSIENT_FAILURE and fails RPCs with an expected status code and message.

(t *testing.T)

// configured. It verifies that the LB policy sets the overall channel state to
// TRANSIENT_FAILURE and fails RPCs with an expected status code and message.
func (s) TestWeightedTarget_NoTargets(t *testing.T) {
	dopts := []grpc.DialOption{
		grpc.WithTransportCredentials(insecure.NewCredentials()),
		grpc.WithDefaultServiceConfig(`{"loadBalancingConfig": [{"weighted_target_experimental":{}}]}`),
	}
	cc, err := grpc.NewClient("passthrough:///test.server", dopts...)
	if err != nil {
		t.Fatalf("grpc.NewClient() failed: %v", err)
	}
	defer cc.Close()
	cc.Connect()

	ctx, cancel := context.WithTimeout(context.Background(), defaultTestTimeout)
	defer cancel()
	client := testgrpc.NewTestServiceClient(cc)
	_, err = client.EmptyCall(ctx, &testpb.Empty{})
	if err == nil {
		t.Error("EmptyCall() succeeded, want failure")
	}
	if gotCode, wantCode := status.Code(err), codes.Unavailable; gotCode != wantCode {
		t.Errorf("EmptyCall() failed with code = %v, want %s", gotCode, wantCode)
	}
	if gotMsg, wantMsg := err.Error(), "no targets to pick from"; !strings.Contains(gotMsg, wantMsg) {
		t.Errorf("EmptyCall() failed with message = %q, want to contain %q", gotMsg, wantMsg)
	}
	if gotState, wantState := cc.GetState(), connectivity.TransientFailure; gotState != wantState {
		t.Errorf("cc.GetState() = %v, want %v", gotState, wantState)
	}
}

// TestWeightedTarget covers the cases that a sub-balancer is added and a
// sub-balancer is removed. It verifies that the addresses and balancer configs