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.view;
  
  import java.io.IOException;
  import java.io.InputStream;
  import java.net.HttpURLConnection;
  import java.util.Collections;
  import java.util.HashMap;
  import java.util.List;
  import java.util.Map;
  
  import org.apache.ambari.server.controller.AmbariManagementController;
  import org.apache.ambari.server.controller.AmbariSessionManager;
  import org.apache.ambari.server.controller.internal.URLStreamProvider;
  import org.apache.ambari.server.proxy.ProxyService;
  import org.apache.ambari.view.AmbariHttpException;
  import org.apache.ambari.view.AmbariStreamProvider;
  import org.apache.commons.io.IOUtils;
  import org.slf4j.Logger;
  import org.slf4j.LoggerFactory;
  
  /**
   * Provider of an input stream for a request to the Ambari server.
   */
  public class ViewAmbariStreamProvider implements AmbariStreamProvider {
    /**
     * Internal stream provider.
     */
    private final URLStreamProvider streamProvider;
  
    /**
     * The Ambari session manager.
     */
    private final AmbariSessionManager ambariSessionManager;
  
    /**
     * The Ambari management controller.
     */
    private final AmbariManagementController controller;
  
    private static final Logger LOG = LoggerFactory.getLogger(ViewAmbariStreamProvider.class);
  
  
    // ----- Constructor -----------------------------------------------------
  
    /**
     * Construct a view Ambari stream provider.
     *
     * @param streamProvider        the underlying stream provider
     * @param ambariSessionManager  the Ambari session manager
     * @param controller         the Ambari configuration
     *
     * @throws IllegalStateException if the Ambari stream provider can not be created
     */
    protected ViewAmbariStreamProvider(URLStreamProvider streamProvider, AmbariSessionManager ambariSessionManager,
                                       AmbariManagementController controller) {
      this.streamProvider       = streamProvider;
      this.ambariSessionManager = ambariSessionManager;
      this.controller           = controller;
    }
  
  
    // ----- AmbariStreamProvider -----------------------------------------------
  
    @Override
    public InputStream readFrom(String path, String requestMethod, String body, Map<String, String> headers
                                ) throws IOException, AmbariHttpException {
      return getInputStream(path, requestMethod, headers, body == null ? null : body.getBytes());
    }
  
    @Override
    public InputStream readFrom(String path, String requestMethod, InputStream body, Map<String, String> headers
                                ) throws IOException, AmbariHttpException {
  
      return getInputStream(path, requestMethod, headers, body == null ? null : IOUtils.toByteArray(body));
    }
  
  
    // ----- helper methods ----------------------------------------------------
  
    private InputStream getInputStream(String path, String requestMethod, Map<String, String> headers
                                       , byte[] body) throws IOException, AmbariHttpException {
      // add the Ambari session cookie to the given headers
      String sessionId = ambariSessionManager.getCurrentSessionId();
      if (sessionId != null) {
  
        String ambariSessionCookie = ambariSessionManager.getSessionCookie() + "=" + sessionId;
  
        if (headers == null || headers.isEmpty()) {
          headers = Collections.singletonMap(URLStreamProvider.COOKIE, ambariSessionCookie);
        } else {
          headers = new HashMap<>(headers);
  
          String cookies = headers.get(URLStreamProvider.COOKIE);
  
          headers.put(URLStreamProvider.COOKIE, URLStreamProvider.appendCookie(cookies, ambariSessionCookie));
        }
      }
  
      // adapt the headers for the internal URLStreamProvider signature
      Map<String, List<String>> headerMap = new HashMap<>();
      for (Map.Entry<String, String> entry : headers.entrySet()) {
        headerMap.put(entry.getKey(), Collections.singletonList(entry.getValue()));
      }
  
      return getInputStream(streamProvider.processURL(controller.getAmbariServerURI(path.startsWith("/") ? path : "/" + path),
          requestMethod, body, headerMap));
    }
  
    private InputStream getInputStream(HttpURLConnection connection) throws IOException, AmbariHttpException {
      int responseCode = connection.getResponseCode();
      if (responseCode >= ProxyService.HTTP_ERROR_RANGE_START) {
        String message = connection.getResponseMessage();
        if (connection.getErrorStream() != null) {
          message = IOUtils.toString(connection.getErrorStream());
        }
        LOG.error("Got error response for url {}. Response code:{}. {}", connection.getURL(), responseCode, message);
        throw new AmbariHttpException(message, responseCode);
      }
      return connection.getInputStream();
    }
  }
  
  