content: /*
   * Copyright 1999-2018 Alibaba Group Holding Ltd.
   *
   * Licensed under the Apache License, Version 2.0 (the "License");
   * you may not use this file except in compliance with the License.
   * You may obtain a copy of the License at
   *
   *      http://www.apache.org/licenses/LICENSE-2.0
   *
   * Unless required by applicable law or agreed to in writing, software
   * distributed under the License is distributed on an "AS IS" BASIS,
   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   * See the License for the specific language governing permissions and
   * limitations under the License.
   */
  
  package com.alibaba.nacos.istio.mcp;
  
  import com.alibaba.nacos.istio.api.ApiGenerator;
  import com.alibaba.nacos.istio.common.ResourceSnapshot;
  import com.alibaba.nacos.istio.misc.IstioConfig;
  import com.alibaba.nacos.istio.model.IstioService;
  import com.alibaba.nacos.istio.model.PushRequest;
  import com.alibaba.nacos.istio.model.ServiceEntryWrapper;
  import com.google.protobuf.Any;
  import istio.mcp.v1alpha1.MetadataOuterClass;
  import istio.mcp.v1alpha1.ResourceOuterClass.Resource;
  import istio.networking.v1alpha3.ServiceEntryOuterClass;
  
  import java.util.ArrayList;
  import java.util.List;
  import java.util.Map;
  
  import static com.alibaba.nacos.istio.api.ApiConstants.SERVICE_ENTRY_PROTO;
  import static com.alibaba.nacos.istio.util.IstioCrdUtil.buildServiceEntry;
  
  /**
   * @author special.fy
   */
  public class ServiceEntryMcpGenerator implements ApiGenerator<Resource> {
      
      private List<ServiceEntryWrapper> serviceEntries;
      
      private static volatile ServiceEntryMcpGenerator singleton = null;
  
      public static ServiceEntryMcpGenerator getInstance() {
          if (singleton == null) {
              synchronized (ServiceEntryMcpGenerator.class) {
                  if (singleton == null) {
                      singleton = new ServiceEntryMcpGenerator();
                  }
              }
          }
          return singleton;
      }
  
      @Override
      public List<Resource> generate(PushRequest pushRequest) {
          List<Resource> result = new ArrayList<>();
          serviceEntries = new ArrayList<>(16);
          ResourceSnapshot resourceSnapshot = pushRequest.getResourceSnapshot();
      
          IstioConfig istioConfig = resourceSnapshot.getIstioConfig();
          Map<String, IstioService> serviceInfoMap = resourceSnapshot.getIstioResources().getIstioServiceMap();
      
          for (Map.Entry<String, IstioService> entry : serviceInfoMap.entrySet()) {
              String serviceName = entry.getKey();
              
              ServiceEntryWrapper serviceEntryWrapper = buildServiceEntry(serviceName, serviceName + istioConfig.getDomainSuffix(), serviceInfoMap.get(serviceName));
              if (serviceEntryWrapper != null) {
                  serviceEntries.add(serviceEntryWrapper);
              }
          }
          
          for (ServiceEntryWrapper serviceEntryWrapper : serviceEntries) {
              MetadataOuterClass.Metadata metadata = serviceEntryWrapper.getMetadata();
              ServiceEntryOuterClass.ServiceEntry serviceEntry = serviceEntryWrapper.getServiceEntry();
  
              Any any = Any.newBuilder().setValue(serviceEntry.toByteString()).setTypeUrl(SERVICE_ENTRY_PROTO).build();
  
              result.add(Resource.newBuilder().setBody(any).setMetadata(metadata).build());
          }
  
          return result;
      }
      
      @Override
      public List<io.envoyproxy.envoy.service.discovery.v3.Resource> deltaGenerate(PushRequest pushRequest) {
          return new ArrayList<>();
      }
  }
  