Repository: grpc/grpc-go
File: health/server_internal_test.go (Go)

Code before:
	// Fill out status map with information
	for i := 1; i <= 3; i++ {
		s.statusMap[fmt.Sprintf("%d", i)] = healthpb.HealthCheckResponse_SERVING
	}
	s.mu.Unlock()

	ctx, cancel := context.WithTimeout(context.Background(), 10*time.Second)
	defer cancel()
	var in healthpb.HealthListRequest
	out, err := s.List(ctx, &in)

	if err != nil {
		t.Fatalf("s.List(ctx, &in) returned err %v, want nil", err)
	}
	if len(out.GetStatuses()) != len(s.statusMap) {
		t.Fatalf("len(out.GetStatuses()) = %d, want %d", len(out.GetStatuses()), len(s.statusMap))
	}
	for key := range out.GetStatuses() {
		v, ok := s.statusMap[key]
		if !ok {
			t.Fatalf("key %s does not exist in s.statusMap", key)
		}
		if v != healthpb.HealthCheckResponse_SERVING {
			t.Fatalf("%s returned status %d, want %d", key, healthpb.HealthCheckResponse_SERVING, v)
		}
	}
}

// TestListResourceExhausted verifies that List() returns a ResourceExhausted error if no. of services are more than
// maxAllowedServices.
func (s) TestListResourceExhausted(t *testing.T) {
	s := NewServer()
	s.mu.Lock()
	// Remove the zero value
	delete(s.statusMap, "")

	// Fill out status map with service information, 101 elements will trigger an error.
	for i := 1; i <= maxAllowedServices+1; i++ {
		s.statusMap[fmt.Sprintf("%d", i)] = healthpb.HealthCheckResponse_SERVING
	}
	s.mu.Unlock()

	ctx, cancel := context.WithTimeout(context.Background(), 10*time.Second)
	defer cancel()
	var in healthpb.HealthListRequest
	_, err := s.List(ctx, &in)

	if err == nil {
		t.Fatalf("s.List(ctx, &in) return nil error, want non-nil")
	}
	if !errors.Is(err, status.Errorf(codes.ResourceExhausted, "server health list exceeds maximum capacity: %d", maxAllowedServices)) {

Review comment (suggestion):
Please replace this with something that confirms it is what we expect it to be statically, not what exists in `s.statusMap` dynamically.  I.e.

```go
want := healthpb.HealthListRequest{
	Statuses: map[string]*healthpb.HealthCheckResponse{
		"1": healthpb.HealthCheckResponse_SERVING.Enum(), // etc
	}
}
if diff := cmp.Diff(got, want); diff != "" {
	t.Fatalf("....: %s", diff)
}
```

Code after:

	// Fill out status map with information
	const length = 3
	for i := 0; i < length; i++ {
		s.SetServingStatus(fmt.Sprintf("%d", i),
			healthpb.HealthCheckResponse_ServingStatus(i))
	}

	ctx, cancel := context.WithTimeout(context.Background(), 10*time.Second)
	defer cancel()
	var in healthpb.HealthListRequest
	got, err := s.List(ctx, &in)

	if err != nil {
		t.Fatalf("s.List(ctx, &in) returned err %v, want nil", err)
	}
	if len(got.GetStatuses()) != length+1 {
		t.Fatalf("len(out.GetStatuses()) = %d, want %d",
			len(got.GetStatuses()), length+1)
	}
	want := &healthpb.HealthListResponse{
		Statuses: map[string]*healthpb.HealthCheckResponse{
			"":  {Status: healthpb.HealthCheckResponse_SERVING},
			"0": {Status: healthpb.HealthCheckResponse_UNKNOWN},
			"1": {Status: healthpb.HealthCheckResponse_SERVING},
			"2": {Status: healthpb.HealthCheckResponse_NOT_SERVING},
		},
	}
	if diff := cmp.Diff(got, want, protocmp.Transform()); diff != "" {
		t.Fatalf("Health response did not match expectation.  Diff (-got, +want): %s", diff)
	}
}

// TestListResourceExhausted verifies that List()
// returns a ResourceExhausted error if no. of services are more than
// maxAllowedServices.
func (s) TestListResourceExhausted(t *testing.T) {
	s := NewServer()

	// Fill out status map with service information,
	// 101 (100 + 1 existing) elements will trigger an error.
	for i := 1; i <= maxAllowedServices; i++ {
		s.SetServingStatus(fmt.Sprintf("%d", i),
			healthpb.HealthCheckResponse_SERVING)
	}

	ctx, cancel := context.WithTimeout(context.Background(), 10*time.Second)
	defer cancel()
	var in healthpb.HealthListRequest
	_, err := s.List(ctx, &in)