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.e2e.lua;
  
  import lombok.RequiredArgsConstructor;
  import org.apache.skywalking.apm.toolkit.trace.TraceContext;
  import org.springframework.http.ResponseEntity;
  import org.springframework.web.bind.annotation.PostMapping;
  import org.springframework.web.bind.annotation.RestController;
  import org.springframework.web.client.RestTemplate;
  
  import java.net.MalformedURLException;
  import java.net.URISyntaxException;
  import java.net.URL;
  import java.util.concurrent.TimeUnit;
  
  @RestController
  @RequiredArgsConstructor
  public class LuaController {
      protected final RestTemplate restTemplate = new RestTemplate();
  
      @PostMapping("/nginx/entry/info")
      private String nginxEntry(String backend) throws MalformedURLException, URISyntaxException {
          final URL url = new URL("http://nginx:8080/nginx/info");
          TraceContext.putCorrelation("entry", "entry_value");
          final ResponseEntity<String> response = restTemplate.postForEntity(url.toURI(), null, String.class);
          return response.getBody();
      }
  
      @PostMapping("/nginx/end/info")
      private String nginxEnd() throws InterruptedException {
          TimeUnit.SECONDS.sleep(1);
  
          return TraceContext.getCorrelation("entry").orElse("")
              + "_" + TraceContext.getCorrelation("nginx").orElse("");
      }
  
  }
  