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.ambari.server.utils;
  
  import java.io.BufferedReader;
  import java.io.InputStream;
  import java.io.InputStreamReader;
  import java.net.HttpURLConnection;
  import java.util.HashMap;
  import java.util.List;
  import java.util.Map;
  
  import org.apache.ambari.server.configuration.ComponentSSLConfiguration;
  import org.apache.ambari.server.controller.internal.URLStreamProvider;
  import org.apache.ambari.server.proxy.ProxyService;
  
  /**
   * Static Helper methods for HTTP requests.
   */
  public class HTTPUtils {
  
    /**
     * Issues a GET request against a URL.
     * @param urlToRead URL to read from
     * @return Returns a response string if successful, and empty otherwise.
     */
    public static String requestURL(String urlToRead) {
      String result = "";
      BufferedReader rd;
      String line = null;
      String url = urlToRead;
  
      try {
        URLStreamProvider urlStreamProvider = new URLStreamProvider(ProxyService.URL_CONNECT_TIMEOUT,
            ProxyService.URL_READ_TIMEOUT, ComponentSSLConfiguration.instance());
  
        Map<String, List<String>> headers = new HashMap<>();
  
        HttpURLConnection connection = urlStreamProvider.processURL(url, "GET", (String) null, headers);
  
        int responseCode = connection.getResponseCode();
        InputStream resultInputStream = null;
        if (responseCode >= ProxyService.HTTP_ERROR_RANGE_START) {
          resultInputStream = connection.getErrorStream();
        } else {
          resultInputStream = connection.getInputStream();
        }
  
        rd = new BufferedReader(new InputStreamReader(resultInputStream));
  
        line = rd.readLine();
        while (line != null) {
          result += line;
          line = rd.readLine();
        }
        rd.close();
      } catch (Exception e) {
        e.printStackTrace();
      }
      return result;
    }
  
    /**
     * Given a property like 0.0.0.0:1234 or c6401.ambari.apache.org:50070
     * will extract the hostname and the port number
     * @param value Address
     * @return Return the host and port if it is a valid string, otherwise null.
     */
    public static HostAndPort getHostAndPortFromProperty(String value) {
      if (value == null || value.isEmpty()) return null;
      value = value.trim();
      int colonIndex = value.indexOf(":");
      if (colonIndex > 0 && colonIndex < value.length() - 1) {
        String host = value.substring(0, colonIndex);
        int port = Integer.parseInt(value.substring(colonIndex + 1, value.length())); // account for the ":"
        return new HostAndPort(host, port);
      }
      return null;
    }
  }
  