br.bireme.scl.CopyMongoDb.java Source code

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Here is the source code for br.bireme.scl.CopyMongoDb.java

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/*=========================================================================
    
Copyright  2013 BIREME/PAHO/WHO
    
This file is part of Social Check Links.
    
Social Check Links is free software: you can redistribute it and/or 
modify it under the terms of the GNU Lesser General Public License as 
published by the Free Software Foundation, either version 2.1 of 
the License, or (at your option) any later version.
    
Social Check Links 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 Lesser General Public License for more details.
    
You should have received a copy of the GNU Lesser General Public 
License along with Social Check Links. If not, see 
<http://www.gnu.org/licenses/>.
    
=========================================================================*/

package br.bireme.scl;

import com.mongodb.DB;
import com.mongodb.DBCollection;
import com.mongodb.DBCursor;
import com.mongodb.DBObject;
import com.mongodb.MongoClient;
import com.mongodb.WriteConcern;
import com.mongodb.WriteResult;
import java.io.IOException;
import java.net.UnknownHostException;
import java.util.Set;

/**
 *
 * @author Heitor Barbieri
 * date 20140114
 */
public class CopyMongoDb {
    private static void copyDB(final String from_host, final String to_host, final String from_db,
            final String to_db, final String from_port, final String to_port, final boolean appendCollections,
            final boolean displayAllIds) throws UnknownHostException, IOException {
        assert from_host != null;
        assert to_host != null;
        assert from_db != null;
        assert to_db != null;
        assert from_port != null;
        assert to_port != null;

        final int MAX_LOOP_SIZE = 15000; // MongoException$CursorNotFound
        final MongoClient fromClient = new MongoClient(from_host, Integer.parseInt(from_port));
        final MongoClient toClient = new MongoClient(to_host, Integer.parseInt(to_port));
        final DB fromDb = fromClient.getDB(from_db);
        final DB toDb = toClient.getDB(to_db);

        if (!appendCollections) {
            toDb.dropDatabase();
        }

        final Set<String> colls = fromDb.getCollectionNames();

        for (String cname : colls) {
            if (cname.equals("system.indexes")) {
                continue;
            }

            final DBCollection fromColl = fromDb.getCollection(cname);
            final DBCollection toColl = toDb.getCollection(cname);

            DBCursor cursor = fromColl.find();
            int curr = 0;

            System.out.println("Copying collection: " + cname);

            while (cursor.hasNext()) {
                if (curr % MAX_LOOP_SIZE == 0) {
                    if (curr > 0) {
                        cursor.close();
                        cursor = fromColl.find().skip(curr);
                        if (!cursor.hasNext()) {
                            throw new IOException("hasNext() failed");
                        }
                    }
                }
                final DBObject doc = cursor.next();
                final WriteResult ret = toColl.save(doc, WriteConcern.ACKNOWLEDGED);

                if (!ret.getCachedLastError().ok()) {
                    System.err.println("write error doc id=" + doc.get("_id"));
                }
                if (++curr % 1000 == 0) {
                    System.out.println("+++" + curr);
                }
                if (displayAllIds) {
                    System.out.println(" id=" + doc.get("_id"));
                }
            }
            cursor.close();

            System.out.println();
        }
    }

    private static void usage() {
        System.err.println("usage: CopyMongoDb <from_host> <to_host> <from_db>"
                + " [-to_db=<name>] [-from_port=<port>] [-to_port=<port>]"
                + " [--appendCollections] [--displayAllIds]");
        System.exit(1);
    }

    public static void main(final String[] args) throws UnknownHostException, IOException {
        if (args.length < 3) {
            usage();
        }
        String toDb = args[2];
        String fromPort = Integer.toString(BrokenLinks.DEFAULT_PORT);
        String toPort = fromPort;
        boolean appendCollections = false;
        boolean displayAllIds = false;

        for (int idx = 3; idx < args.length; idx++) {
            if (args[idx].startsWith("-to_db=")) {
                toDb = args[idx].substring(7);
            } else if (args[idx].startsWith("-from_port=")) {
                fromPort = args[idx].substring(11);
            } else if (args[idx].startsWith("-to_port=")) {
                toPort = args[idx].substring(9);
            } else if (args[idx].equals("--appendCollections")) {
                appendCollections = true;
            } else if (args[idx].equals("--displayAllIds")) {
                displayAllIds = true;
            } else {
                usage();
            }
        }

        copyDB(args[0], args[1], args[2], toDb, fromPort, toPort, appendCollections, displayAllIds);
    }
}