eml.studio.server.oozie.workflow.WFGraph.java Source code

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Here is the source code for eml.studio.server.oozie.workflow.WFGraph.java

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/**
 * Copyright 2017 Institute of Computing Technology, Chinese Academy of Sciences.
 * Licensed under the terms of the Apache 2.0 license.
 * Please see LICENSE file in the project root for terms
 */
package eml.studio.server.oozie.workflow;

import java.io.StringWriter;
import java.util.HashMap;
import java.util.LinkedList;
import java.util.List;
import java.util.Map;
import java.util.Queue;

import org.dom4j.Document;
import org.dom4j.DocumentHelper;
import org.dom4j.Element;
import org.dom4j.Namespace;
import org.dom4j.QName;
import org.dom4j.io.OutputFormat;
import org.dom4j.io.XMLWriter;

/**
 * The workflow graph description
 *
 */
public class WFGraph {

    protected Map<String, NodeDef> nodeMap = new HashMap<String, NodeDef>();

    protected NodeDef start = new StartNodeDef();
    protected NodeDef end = new EndNodeDef();

    /**
     * nodes that will be execute in the Oozie Job
     * @param action the action added to Oozie
     * @throws Exception
     */
    public void addActionNode(NodeDef action) throws Exception {
        nodeMap.put(action.getName(), action);
    }

    /**
     * Add fill output file path to node output node
     *  
     * @param nodeId   Node id
     * @param files Output file name list
     * @param workPath  App work path
     */
    public void addNodeOutputFile(String nodeId, List<String> files, String workPath) {
        NodeDef node = nodeMap.get(nodeId);
        if (node != null) {
            for (int i = 0; i < files.size(); i++) {
                if (workPath != null) {
                    String totalPath = workPath + files.get(i);
                    node.putOutputFile(i, totalPath);
                } else
                    node.putOutputFile(i, files.get(i));
            }
        }
    }

    /**
     * Add edge from source node to destination node
     * @param srcNodeId the source node id
     * @param dstNodeId the destination node id
     * @param srcNodePort the source node port
     * @param dstNodePort the destination node port
     * @param file the file name of dataflow this edge respected to
     */
    public void addEdge(String srcNodeId, String dstNodeId, int srcNodePort, int dstNodePort, String file) {
        NodeDef srcNode = nodeMap.get(srcNodeId);
        NodeDef dstNode = nodeMap.get(dstNodeId);
        if (srcNode != null && dstNode != null) {
            srcNode.addOutNode(dstNode);
            dstNode.addInNode(srcNode);
        }

        if (dstNode != null)
            dstNode.putInputFile(dstNodePort, file);
    }

    /**
     * Transform the Graph into an workflow xml definition
     * @param jobname the job name of Oozie job, can't be null
     * @return workflow xml
     */
    public String toWorkflow(String jobname) {
        Namespace xmlns = new Namespace("", "uri:oozie:workflow:0.4"); // root namespace uri
        QName qName = QName.get("workflow-app", xmlns); // your root element's name
        Element workflow = DocumentHelper.createElement(qName);
        Document xmldoc = DocumentHelper.createDocument(workflow);
        // Create workflow root
        workflow.addAttribute("xmlns", "uri:oozie:workflow:0.4");
        // <workflow-app name='xxx'></workflow-app>
        if (jobname == null || "".equals(jobname))
            workflow.addAttribute("name", "Not specified");
        else
            workflow.addAttribute("name", jobname);

        Queue<NodeDef> que = new LinkedList<NodeDef>();
        que.add(start);

        while (!que.isEmpty()) {
            NodeDef cur = que.remove();

            cur.append2XML(workflow);

            for (NodeDef toNode : cur.getOutNodes()) {
                toNode.delInNode(cur);
                if (toNode.getInDegree() == 0)
                    que.add(toNode);
            }
        }

        // Set XML document format
        OutputFormat outputFormat = OutputFormat.createPrettyPrint();
        // Set XML encoding, use the specified encoding to save the XML document to the string, it can be specified GBK or ISO8859-1
        outputFormat.setEncoding("UTF-8");
        outputFormat.setSuppressDeclaration(true); // Whether generate xml header
        outputFormat.setIndent(true); // Whether set indentation
        outputFormat.setIndent("    "); // Implement indentation with four spaces
        outputFormat.setNewlines(true); // Set whether to wrap

        try {
            // stringWriter is used to save xml document
            StringWriter stringWriter = new StringWriter();
            // xmlWriter is used to write XML document to string(tool)
            XMLWriter xmlWriter = new XMLWriter(stringWriter, outputFormat);

            // Write the created XML document into the string
            xmlWriter.write(xmldoc);

            xmlWriter.close();

            System.out.println(stringWriter.toString().trim());
            // Print the string, that is, the XML document
            return stringWriter.toString().trim();

        } catch (Exception ex) {
            ex.printStackTrace();
        }
        return null;
    }

    public static void main(String args[]) {

        Namespace rootNs = new Namespace("", "uri:oozie:workflow:0.4"); // root namespace uri
        QName rootQName = QName.get("workflow-app", rootNs); // your root element's name
        Element workflow = DocumentHelper.createElement(rootQName);
        Document doc = DocumentHelper.createDocument(workflow);

        workflow.addAttribute("name", "test");
        Element test = workflow.addElement("test");
        test.addText("hello");
        OutputFormat outputFormat = OutputFormat.createPrettyPrint();
        outputFormat.setEncoding("UTF-8");
        outputFormat.setIndent(true);
        outputFormat.setIndent("    ");
        outputFormat.setNewlines(true);
        try {
            StringWriter stringWriter = new StringWriter();
            XMLWriter xmlWriter = new XMLWriter(stringWriter);
            xmlWriter.write(doc);
            xmlWriter.close();
            System.out.println(doc.asXML());
            System.out.println(stringWriter.toString().trim());

        } catch (Exception ex) {
            ex.printStackTrace();
        }
    }

}