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.consistency;
  
  import com.alibaba.nacos.consistency.entity.GetRequest;
  import com.alibaba.nacos.consistency.entity.Log;
  import com.alibaba.nacos.consistency.entity.ReadRequest;
  import com.alibaba.nacos.consistency.entity.WriteRequest;
  import com.alibaba.nacos.consistency.exception.ConsistencyException;
  import com.google.protobuf.Message;
  
  /**
   * protobuf message utils.
   *
   * @author <a href="mailto:liaochuntao@live.com">liaochuntao</a>
   */
  public class ProtoMessageUtil {
      
      /**
       * should be different from field tags of ReadRequest or WriteQuest.
       */
      public static final int REQUEST_TYPE_FIELD_TAG = 7 << 3;
      
      public static final int REQUEST_TYPE_READ = 1;
      
      public static final int REQUEST_TYPE_WRITE = 2;
      
      /**
       * Converts the byte array to a specific Protobuf object.
       * Internally, the protobuf new and old objects are compatible.
       *
       * @param bytes An array of bytes
       * @return Message
       */
      public static Message parse(byte[] bytes) {
          Message result;
          try {
              if (bytes[0] == REQUEST_TYPE_FIELD_TAG) {
                  if (bytes[1] == REQUEST_TYPE_READ) {
                      result = ReadRequest.parseFrom(bytes);
                  } else {
                      result = WriteRequest.parseFrom(bytes);
                  }
                  return result;
              }
          } catch (Throwable ignore) {
          }
          
          // old consistency entity, will be @Deprecated in future
          try {
              GetRequest request = GetRequest.parseFrom(bytes);
              return convertToReadRequest(request);
          } catch (Throwable ignore) {
          }
          
          try {
              Log log = Log.parseFrom(bytes);
              return convertToWriteRequest(log);
          } catch (Throwable ignore) {
          }
          
          throw new ConsistencyException("The current array cannot be serialized to the corresponding object");
      }
      
      /**
       * convert Log to WriteRequest.
       *
       * @param log log
       * @return {@link WriteRequest}
       */
      public static WriteRequest convertToWriteRequest(Log log) {
          return WriteRequest.newBuilder().setKey(log.getKey()).setGroup(log.getGroup())
                  .setData(log.getData())
                  .setType(log.getType())
                  .setOperation(log.getOperation())
                  .putAllExtendInfo(log.getExtendInfoMap())
                  .build();
      }
      
      /**
       * convert Log to ReadRequest.
       *
       * @param request request
       * @return {@link ReadRequest}
       */
      public static ReadRequest convertToReadRequest(GetRequest request) {
          return ReadRequest.newBuilder()
                  .setGroup(request.getGroup())
                  .setData(request.getData())
                  .putAllExtendInfo(request.getExtendInfoMap())
                  .build();
      }
  }
  