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.view.commons.hdfs;
  
  import org.apache.ambari.view.ViewContext;
  import org.apache.ambari.view.commons.exceptions.ServiceFormattedException;
  import org.apache.ambari.view.utils.hdfs.HdfsApi;
  import org.apache.ambari.view.utils.hdfs.HdfsUtil;
  import org.apache.hadoop.security.UserGroupInformation;
  import org.slf4j.Logger;
  import org.slf4j.LoggerFactory;
  
  import javax.ws.rs.WebApplicationException;
  import javax.xml.bind.annotation.XmlRootElement;
  import java.io.IOException;
  import java.util.HashMap;
  import java.util.List;
  import java.util.Map;
  
  /**
   * Base Hdfs service
   */
  public abstract class HdfsService {
  
    protected static final Logger logger = LoggerFactory.getLogger(HdfsService.class);
  
    protected final ViewContext context;
    private Map<String, String> customProperties;
  
    /**
     * Constructor
     * @param context View Context instance
     */
    public HdfsService(ViewContext context) {
      this.context = context;
    }
  
    public HdfsService(ViewContext context, Map<String, String> customProperties) {
      this.context = context;
      this.customProperties = customProperties;
    }
  
    /**
     * Wrapper for json mapping of result of Multi Remove Request
     */
    @XmlRootElement
    public static class FileOperationResult {
      public boolean success;
      public String message;
      public List<String> succeeded;
      public List<String> failed;
      public List<String> unprocessed;
  
      public FileOperationResult(boolean success) {
        this.success = success;
      }
  
      public FileOperationResult(boolean success, String message) {
        this(success);
        this.message = message;
      }
  
      public FileOperationResult(boolean success, String message, List<String> succeeded, List<String> failed, List<String> unprocessed) {
        this(success, message);
        this.succeeded = succeeded;
        this.failed = failed;
        this.unprocessed = unprocessed;
      }
  
    }
  
    private HdfsApi _api = null;
  
    /**
     * Ger HdfsApi instance
     * @return HdfsApi business delegate
     */
    public HdfsApi getApi() {
      if (_api == null) {
        try {
          if(this.customProperties != null){
            _api = HdfsUtil.connectToHDFSApi(context, customProperties);
          }else{
            _api = HdfsUtil.connectToHDFSApi(context);
          }
        } catch (Exception ex) {
          logger.error("Exception while connecting to hdfs : {}", ex.getMessage(), ex);
          throw new ServiceFormattedException("HdfsApi connection failed. Check \"webhdfs.url\" property", ex);
        }
      }
      return _api;
    }
  
    private static Map<String, String> getHdfsAuthParams(ViewContext context) {
      String auth = context.getProperties().get("webhdfs.auth");
      Map<String, String> params = new HashMap<String, String>();
      if (auth == null || auth.isEmpty()) {
        auth = "auth=SIMPLE";
      }
      for(String param : auth.split(";")) {
        String[] keyvalue = param.split("=");
        if (keyvalue.length != 2) {
          logger.error("Can not parse authentication param " + param + " in " + auth);
          continue;
        }
        params.put(keyvalue[0], keyvalue[1]);
      }
      return params;
    }
  
    /**
     * Get doAs username to use in HDFS
     * @param context View Context instance
     * @return user name
     */
    public String getDoAsUsername(ViewContext context) {
      String username = context.getProperties().get("webhdfs.username");
      if (username == null || username.isEmpty())
        username = context.getUsername();
      return username;
    }
  
    /**
     * Checks connection to HDFS
     * @param context View Context
     */
    public static void hdfsSmokeTest(ViewContext context) {
      try {
        HdfsApi api = HdfsUtil.connectToHDFSApi(context);
        api.getStatus();
      } catch (WebApplicationException ex) {
        throw ex;
      } catch (Exception ex) {
        throw new ServiceFormattedException(ex.getMessage(), ex);
      }
    }
  
    /**
     * Get proxyuser username to use in HDFS
     * @param context View Context instance
     * @return user name
     */
    public String getRealUsername(ViewContext context) {
      String username = context.getProperties().get("webhdfs.proxyuser");
      if (username == null || username.isEmpty())
        try {
          username = UserGroupInformation.getCurrentUser().getShortUserName();
        } catch (IOException e) {
          throw new ServiceFormattedException("HdfsApi connection failed. Can't get current user", e);
        }
      return username;
    }
  }
  