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.analyzer.provider.trace.parser;
  
  /**
   * Reserved keys of the span. The backend analysis the metrics according the existed tags.
   */
  public class SpanTags {
      public static final String HTTP_RESPONSE_STATUS_CODE = "http.status_code";
      /**
       * Deprecated. The old status_code tag, in order to be compatible with the old version of agent.
       * It should be replaced by {@link #HTTP_RESPONSE_STATUS_CODE} or using
       * {@link #RPC_RESPONSE_STATUS_CODE} if status code is related to a rpc call.
       */
      @Deprecated
      public static final String STATUS_CODE = "status_code";
  
      public static final String RPC_RESPONSE_STATUS_CODE = "rpc.status_code";
  
      public static final String DB_STATEMENT = "db.statement";
  
      public static final String DB_TYPE = "db.type";
  
      public static final String CACHE_TYPE = "cache.type";
  
      public static final String CACHE_OP = "cache.op";
  
      public static final String CACHE_CMD = "cache.cmd";
  
      public static final String CACHE_KEY = "cache.key";
  
      public static final String MQ_QUEUE = "mq.queue";
  
      public static final String MQ_TOPIC = "mq.topic";
  
      public static final String TRANSMISSION_LATENCY = "transmission.latency";
  
      /**
       * Tag, x-le(extension logic endpoint) series tag. Value is JSON format.
       * <pre>
       * {
       *   "name": "GraphQL-service",
       *   "latency": 100,
       *   "status": true
       * }
       * </pre>
       *
       * Also, could use value to indicate this local span is representing a logic endpoint.
       * <pre>
       * {
       *   "logic-span": true
       * }
       * </pre>
       */
      public static final String LOGIC_ENDPOINT = "x-le";
  }
  