com.athena.dolly.cloudant.CloudantEventListener.java Source code

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Here is the source code for com.athena.dolly.cloudant.CloudantEventListener.java

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/* 
 * Athena Dolly Project 
 * 
 * Copyright (C) 2013 Open Source Consulting, Inc. All rights reserved by Open Source Consulting, Inc.
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * as published by the Free Software Foundation; either version 2
 * of the License, or (at your option) any later version.
 * 
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 * 
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
 *
 * Revision History
 * Author         Date            Description
 * ---------------   ----------------   ------------
 * Jerry Jung      2013. 12. 30.      First Draft.
 */
package com.athena.dolly.cloudant;

import java.net.MalformedURLException;
import java.util.ArrayList;
import java.util.Iterator;
import java.util.List;

import org.ektorp.CouchDbConnector;
import org.ektorp.ViewQuery;
import org.ektorp.ViewResult;
import org.ektorp.ViewResult.Row;
import org.ektorp.changes.ChangesCommand;
import org.ektorp.changes.ChangesFeed;
import org.ektorp.changes.DocumentChange;
import org.ektorp.http.HttpClient;
import org.ektorp.http.StdHttpClient;
import org.ektorp.impl.StdCouchDbInstance;

import com.fasterxml.jackson.databind.JsonNode;
import com.fasterxml.jackson.databind.ObjectMapper;
import com.fasterxml.jackson.databind.node.ObjectNode;

public class CloudantEventListener {
    static String url = System.getProperty("url", "https://jerryj3.cloudant.com");
    CouchDbConnector conn;
    CouchDbConnector connSeq;
    ChangesCommand cmd;

    public static void main(String args[]) {
        CloudantEventListener listener = new CloudantEventListener();
        listener.init();

        SFile sFile = listener.getSFileByAbsolutePath("/stroage/media/a.jpg");
        System.out.println("Query by absolutePath: " + sFile);

        while (true) {
            List<SFile> sFiles = listener.waitForMeta();
        }
    }

    public void init() {
        try {
            HttpClient httpClient = new StdHttpClient.Builder().url(url).username("ighlyesesedisentstoldneg")
                    .password("cOlugjOsPXtkHyR1SPvNDYME").connectionTimeout(5000).socketTimeout(30000).build();

            StdCouchDbInstance dbInst = new StdCouchDbInstance(httpClient);

            System.out.println("*** Database connection is established");

            conn = dbInst.createConnector("a_samsung_file", true);
            connSeq = dbInst.createConnector("a_seq", true);

        } catch (MalformedURLException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
    }

    public List<SFile> waitForMeta() {
        List<SFile> result = new ArrayList<SFile>();

        JsonNode a_samsung_file = (JsonNode) connSeq.find(JsonNode.class, "a_samsung_file");
        if (a_samsung_file != null) {
            System.out.println("Since: " + a_samsung_file.get("seq").textValue());
            cmd = new ChangesCommand.Builder().since(a_samsung_file.get("seq").textValue()).includeDocs(true)
                    .build();
        } else {
            cmd = new ChangesCommand.Builder().includeDocs(true).build();
        }

        //   Event Process
        ChangesFeed feed = conn.changesFeed(cmd);
        while (feed.isAlive()) {
            DocumentChange change = null;
            try {
                System.out.println("Waiting...");

                change = feed.next();
                //               change = feed.next(5, TimeUnit.SECONDS);
            } catch (InterruptedException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }

            if (change != null) {
                DocumentChange newChange = null;
                do {
                    String docId = change.getId();
                    JsonNode changedDoc = change.getDocAsNode();
                    ObjectMapper om = new ObjectMapper();
                    SFile aFile = om.convertValue(changedDoc, SFile.class);
                    result.add(aFile);

                    System.out.println(changedDoc + ", seq=" + change.getStringSequence());
                    try {
                        newChange = feed.poll();
                    } catch (InterruptedException e) {
                        // TODO Auto-generated catch block
                        e.printStackTrace();
                    }
                } while (newChange != null);

                //    ? ? seq  
                if (a_samsung_file == null) {
                    ObjectMapper om = new ObjectMapper();
                    a_samsung_file = om.createObjectNode();
                    ((ObjectNode) a_samsung_file).put("_id", "a_samsung_file");
                    ((ObjectNode) a_samsung_file).put("seq", change.getStringSequence());
                    connSeq.create(a_samsung_file);
                } else {
                    ((ObjectNode) a_samsung_file).put("seq", change.getStringSequence());
                    connSeq.update(a_samsung_file);
                }
            }
        }

        return result;
    }

    public SFile getSFileByAbsolutePath(String absolutePath) {
        ObjectMapper om = new ObjectMapper();
        ViewQuery query = new ViewQuery().designDocId("_design/index").viewName("absPathView").key(absolutePath)
                .includeDocs(true).limit(1).staleOk(false);
        ViewResult result = conn.queryView(query);
        Iterator<Row> it = result.iterator();
        while (it.hasNext()) {
            Row row = it.next();
            //         System.out.println(row);
            //         System.out.println(row.getDocAsNode());
            SFile sFile = om.convertValue(row.getDocAsNode(), SFile.class);
            return sFile;
        }

        return null;
    }
}