code: /*
   * Licensed to the Apache Software Foundation (ASF) under one or more
   * contributor license agreements.  See the NOTICE file distributed with
   * this work for additional information regarding copyright ownership.
   * The ASF licenses this file to You 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 org.apache.skywalking.oap.server.core.remote.health;
  
  import grpc.health.v1.HealthCheckService;
  import grpc.health.v1.HealthGrpc;
  import io.grpc.stub.StreamObserver;
  import org.apache.skywalking.oap.server.library.server.grpc.GRPCHandler;
  import org.slf4j.Logger;
  import org.slf4j.LoggerFactory;
  
  public class HealthCheckServiceHandler extends HealthGrpc.HealthImplBase implements GRPCHandler {
  
      private static final Logger LOGGER = LoggerFactory.getLogger(HealthCheckServiceHandler.class);
  
      /**
       * By my test, consul didn't send the service.
       *
       * @param request          service
       * @param responseObserver status
       */
      @Override
      public void check(HealthCheckService.HealthCheckRequest request,
          StreamObserver<HealthCheckService.HealthCheckResponse> responseObserver) {
  
          if (LOGGER.isDebugEnabled()) {
              LOGGER.debug("Received the gRPC server health check with the service name of {}", request.getService());
          }
  
          HealthCheckService.HealthCheckResponse.Builder response = HealthCheckService.HealthCheckResponse.newBuilder();
          response.setStatus(HealthCheckService.HealthCheckResponse.ServingStatus.SERVING);
  
          responseObserver.onNext(response.build());
          responseObserver.onCompleted();
      }
  }
  