String stackVersion = request.getStackVersion();
String serviceName = request.getServiceName();
if (serviceName != null) {
ServiceInfo service = this.ambariMetaInfo.getService(stackName, stackVersion, serviceName);
response = Collections.singleton(service.convertToResponse());
} else {
Map<String, ServiceInfo> services = this.ambariMetaInfo.getServices(stackName, stackVersion);
response = new HashSet<StackServiceResponse>();
for (ServiceInfo service : services.values()) {
response.add(service.convertToResponse());