001 /** 002 * Licensed to the Apache Software Foundation (ASF) under one 003 * or more contributor license agreements. See the NOTICE file 004 * distributed with this work for additional information 005 * regarding copyright ownership. The ASF licenses this file 006 * to you under the Apache License, Version 2.0 (the 007 * "License"); you may not use this file except in compliance 008 * with the License. You may obtain a copy of the License at 009 * 010 * http://www.apache.org/licenses/LICENSE-2.0 011 * 012 * Unless required by applicable law or agreed to in writing, software 013 * distributed under the License is distributed on an "AS IS" BASIS, 014 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 015 * See the License for the specific language governing permissions and 016 * limitations under the License. 017 */ 018 package org.apache.oozie.action.hadoop; 019 020 import java.io.ByteArrayInputStream; 021 import java.io.IOException; 022 import java.io.InputStream; 023 import java.util.Collection; 024 025 import org.apache.hadoop.conf.Configuration; 026 import org.apache.oozie.service.HadoopAccessorService; 027 import org.xml.sax.SAXException; 028 import org.w3c.dom.Document; 029 import org.w3c.dom.NodeList; 030 031 import javax.xml.parsers.DocumentBuilderFactory; 032 import javax.xml.parsers.DocumentBuilder; 033 import javax.xml.parsers.ParserConfigurationException; 034 035 /** 036 * Utility class to perform operations on the prepare block of Workflow 037 * 038 */ 039 public class PrepareActionsDriver { 040 041 /** 042 * Method to parse the prepare XML and execute the corresponding prepare actions 043 * 044 * @param prepareXML Prepare XML block in string format 045 * @throws LauncherException 046 */ 047 static void doOperations(Collection<String> supportedFileSystems, String prepareXML) throws LauncherException { 048 try { 049 Document doc = getDocumentFromXML(prepareXML); 050 doc.getDocumentElement().normalize(); 051 052 // Get the list of child nodes, basically, each one corresponding to a separate action 053 NodeList nl = doc.getDocumentElement().getChildNodes(); 054 FileSystemActions fsActions = new FileSystemActions(supportedFileSystems); 055 056 for (int i = 0; i < nl.getLength(); ++i) { 057 String commandType = ""; 058 /* Logic to find the command type goes here 059 commandType = ..........; 060 */ 061 // As of now, the available prepare action is of type hdfs. Hence, assigning the value directly 062 commandType = "hdfs"; 063 if (commandType.equalsIgnoreCase("hdfs")) { 064 fsActions.execute(nl.item(i)); 065 } /*else if(commandType.equalsIgnoreCase("hcat")) { //Other command types go here 066 hCatActions.execute(nl.item(i)); 067 }*/ 068 } 069 } catch (IOException ioe) { 070 throw new LauncherException(ioe.getMessage(), ioe); 071 } catch (SAXException saxe) { 072 throw new LauncherException(saxe.getMessage(), saxe); 073 } catch (ParserConfigurationException pce) { 074 throw new LauncherException(pce.getMessage(), pce); 075 } 076 } 077 078 // Method to return the document from the prepare XML block 079 static Document getDocumentFromXML(String prepareXML) throws ParserConfigurationException, SAXException, 080 IOException { 081 DocumentBuilderFactory docBuilderFactory = DocumentBuilderFactory.newInstance(); 082 DocumentBuilder docBuilder = docBuilderFactory.newDocumentBuilder(); 083 InputStream is = new ByteArrayInputStream(prepareXML.getBytes("UTF-8")); 084 return docBuilder.parse(is); 085 } 086 }