content: /*
   * 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.bookkeeper.server.http.service;
  
  import static com.google.common.base.Preconditions.checkNotNull;
  
  import lombok.Data;
  import lombok.NoArgsConstructor;
  import org.apache.bookkeeper.bookie.Bookie;
  import org.apache.bookkeeper.bookie.StateManager;
  import org.apache.bookkeeper.common.util.JsonUtil;
  import org.apache.bookkeeper.http.HttpServer;
  import org.apache.bookkeeper.http.service.HttpEndpointService;
  import org.apache.bookkeeper.http.service.HttpServiceRequest;
  import org.apache.bookkeeper.http.service.HttpServiceResponse;
  
  /**
   * HttpEndpointService that exposes the current state of the bookie.
   *
   * <p>Get the current bookie status:
   *
   * <pre>
   * <code>
   * {
   *  "running" : true,
   *  "readOnly" : false,
   *  "shuttingDown" : false,
   *  "availableForHighPriorityWrites" : true
   *}
   * </code>
   * </pre>
   */
  public class BookieStateService implements HttpEndpointService {
  
      private final Bookie bookie;
  
      public BookieStateService(Bookie bookie) {
          this.bookie = checkNotNull(bookie);
      }
  
      /**
       * POJO definition for the bookie state response.
       */
      @Data
      @NoArgsConstructor
      public static class BookieState {
          private boolean running;
          private boolean readOnly;
          private boolean shuttingDown;
          private boolean availableForHighPriorityWrites;
      }
  
      @Override
      public HttpServiceResponse handle(HttpServiceRequest request) throws Exception {
          HttpServiceResponse response = new HttpServiceResponse();
  
          if (HttpServer.Method.GET != request.getMethod()) {
              response.setCode(HttpServer.StatusCode.NOT_FOUND);
              response.setBody("Only support GET method to retrieve bookie state.");
              return response;
          }
  
          StateManager sm = bookie.getStateManager();
          BookieState bs = new BookieState();
          bs.running = sm.isRunning();
          bs.readOnly = sm.isReadOnly();
          bs.shuttingDown = sm.isShuttingDown();
          bs.availableForHighPriorityWrites = sm.isAvailableForHighPriorityWrites();
  
          String jsonResponse = JsonUtil.toJson(bs);
          response.setBody(jsonResponse);
          response.setCode(HttpServer.StatusCode.OK);
          return response;
      }
  }
  