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
   * <p>
   * http://www.apache.org/licenses/LICENSE-2.0
   * <p>
   * 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.oozie.ambari.view;
  
  import com.google.common.base.Optional;
  import org.apache.ambari.view.ViewContext;
  import org.apache.ambari.view.commons.hdfs.UserService;
  import org.apache.ambari.view.commons.hdfs.ViewPropertyHelper;
  import org.apache.ambari.view.utils.hdfs.ConfigurationBuilder;
  import org.apache.ambari.view.utils.hdfs.HdfsApi;
  import org.apache.ambari.view.utils.hdfs.HdfsApiException;
  import org.apache.ambari.view.utils.hdfs.HdfsUtil;
  import org.apache.hadoop.conf.Configuration;
  import org.apache.hadoop.fs.FSDataInputStream;
  import org.apache.hadoop.fs.FSDataOutputStream;
  import org.apache.hadoop.fs.FileStatus;
  import org.slf4j.Logger;
  import org.slf4j.LoggerFactory;
  
  import java.io.FileNotFoundException;
  import java.io.IOException;
  import java.net.URI;
  import java.net.URISyntaxException;
  import java.util.HashMap;
  import java.util.Map;
  import java.util.Arrays;
  import java.util.List;
  import java.util.LinkedList;
  
  public class HDFSFileUtils {
  	public static final String VIEW_CONF_KEYVALUES = "view.conf.keyvalues";
  	private static final String DEFAULT_FS = "fs.defaultFS";
  	private static final String AMBARI_SKIP_HOME_DIRECTORY_CHECK_PROTOCOL_LIST = "views.skip.home-directory-check.file-system.list";
  	private final static Logger LOGGER = LoggerFactory
  			.getLogger(HDFSFileUtils.class);
  	private ViewContext viewContext;
  
  	public HDFSFileUtils(ViewContext viewContext) {
  		super();
  		this.viewContext = viewContext;
  	}
  
  	public boolean fileExists(String path) {
  		try {
  			return getHdfsgetApi().exists(path);
  		} catch (IOException e) {
  			LOGGER.error(e.getMessage(), e);
  			throw new RuntimeException(e);
  		} catch (InterruptedException e) {
  			LOGGER.error(e.getMessage(), e);
  			throw new RuntimeException(e);
  		}
  	}
  
  	public FSDataInputStream read(String filePath) throws IOException {
  		FSDataInputStream is;
  		try {
  			is = getHdfsgetApi().open(filePath);
  		} catch (InterruptedException e) {
  			throw new RuntimeException(e);
  		}
  		return is;
  	}
  
  	public String writeToFile(String filePath, String content, boolean overwrite)
  			throws IOException {
  		FSDataOutputStream fsOut;
  		try {
  			fsOut = getHdfsgetApi().create(filePath, overwrite);
  		} catch (InterruptedException e) {
  			throw new RuntimeException(e);
  		}
  		fsOut.write(content.getBytes());
  		fsOut.close();
  		return filePath;
  	}
  
  	public void deleteFile(String filePath) throws IOException {
  		try {
  			getHdfsgetApi().delete(filePath, false);
  		} catch (InterruptedException e) {
  			throw new RuntimeException(e);
  		}
  	}
  
  	private HdfsApi getHdfsgetApi() {
  		try {
  			Optional<Map<String, String>> props = ViewPropertyHelper.getViewConfigs(viewContext, VIEW_CONF_KEYVALUES);
  			HdfsApi api;
  			if(props.isPresent()){
  				api = HdfsUtil.connectToHDFSApi(viewContext, props.get());
  			}else{
  				api = HdfsUtil.connectToHDFSApi(viewContext);
  			}
  
  			return api;
  		} catch (Exception ex) {
  			LOGGER.error("Error in getting HDFS Api", ex);
  			throw new RuntimeException(
  					"HdfsApi connection failed. Check \"webhdfs.url\" property",
  					ex);
  		}
  	}
  
  	public Boolean shouldCheckForHomeDir(){
  		Optional<Map<String, String>> viewConfigs = ViewPropertyHelper.getViewConfigs(viewContext, VIEW_CONF_KEYVALUES);
  		ConfigurationBuilder configBuilder;
  		if(viewConfigs.isPresent()) {
  			configBuilder = new ConfigurationBuilder(this.viewContext, viewConfigs.get());
  		}else{
  			configBuilder = new ConfigurationBuilder(this.viewContext);
  		}
  		Configuration configurations = null;
  		try {
  			configurations = configBuilder.buildConfig();
  		} catch (HdfsApiException e) {
  			throw	 new RuntimeException(e);
  		}
  		String defaultFS = configurations.get(DEFAULT_FS);
  		try {
  			URI fsUri = new URI(defaultFS);
  			String protocol = fsUri.getScheme();
  			String ambariSkipCheckValues = viewContext.getAmbariProperty(AMBARI_SKIP_HOME_DIRECTORY_CHECK_PROTOCOL_LIST);
  			List<String> protocolSkipList = (ambariSkipCheckValues == null? new LinkedList<String>() : Arrays.asList(ambariSkipCheckValues.split(",")));
  			if(null != protocol && protocolSkipList.contains(protocol)){
  				return Boolean.FALSE;
  			}
  		} catch (URISyntaxException e) {
  			LOGGER.error("Error occurred while parsing the defaultFS URI.", e);
  			return Boolean.TRUE;
  		}
  		return Boolean.TRUE;
  	}
  
  	public FileStatus getFileStatus(String filePath) {
  		try {
  			return getHdfsgetApi().getFileStatus(filePath);
  		} catch (FileNotFoundException e) {
  			throw new RuntimeException(e);
  		} catch (IOException e) {
  			throw new RuntimeException(e);
  		} catch (InterruptedException e) {
  			throw new RuntimeException(e);
  		}
  
  	}
  	public boolean hdfsCheck()  {
  		try {
  			getHdfsgetApi().getStatus();
  			return true;
  		} catch (Exception e) {
  			throw new RuntimeException(e);
  		}
  	}
  
  	public boolean homeDirCheck(){
  		UserService userservice = new UserService(viewContext, getViewConfigs(viewContext));
  		userservice.homeDir();
  		return true;
  	}
  	private Map<String,String> getViewConfigs(ViewContext context) {
  		Optional<Map<String, String>> props = ViewPropertyHelper.getViewConfigs(context, VIEW_CONF_KEYVALUES);
  		return props.isPresent()? props.get() : new HashMap<String, String>();
  	}
  }
  