druid.examples.flights.FlightsFirehoseFactory.java Source code

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Here is the source code for druid.examples.flights.FlightsFirehoseFactory.java

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/*
 * Druid - a distributed column store.
 * Copyright (C) 2012  Metamarkets Group 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.
 */

package druid.examples.flights;

import com.fasterxml.jackson.annotation.JsonCreator;
import com.fasterxml.jackson.annotation.JsonProperty;
import com.google.common.base.Charsets;
import com.google.common.base.Throwables;
import com.google.common.collect.Iterators;
import com.google.common.io.Closeables;
import com.metamx.druid.indexer.data.StringInputRowParser;
import com.metamx.druid.input.InputRow;
import com.metamx.druid.realtime.firehose.Firehose;
import com.metamx.druid.realtime.firehose.FirehoseFactory;

import java.io.BufferedReader;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.util.Iterator;
import java.util.zip.GZIPInputStream;

/**
 */
public class FlightsFirehoseFactory implements FirehoseFactory {
    private final String flightsFileLocation;
    private final StringInputRowParser parser;

    @JsonCreator
    public FlightsFirehoseFactory(@JsonProperty("directory") String flightsFilesDirectory,
            @JsonProperty("parser") StringInputRowParser parser) {
        this.flightsFileLocation = flightsFilesDirectory;
        this.parser = parser;
    }

    @JsonProperty("directory")
    public String getFlightsFileLocation() {
        return flightsFileLocation;
    }

    @Override
    public Firehose connect() throws IOException {
        File dir = new File(flightsFileLocation);

        final Iterator<File> files = Iterators.forArray(dir.listFiles());

        return new Firehose() {
            BufferedReader in = null;
            String line = null;

            @Override
            public boolean hasMore() {
                try {
                    if (line != null) {
                        return true;
                    } else if (in != null) {
                        line = in.readLine();

                        if (line == null) {
                            Closeables.closeQuietly(in);
                            in = null;
                        }

                        return true;
                    } else if (files.hasNext()) {
                        final File nextFile = files.next();

                        if (nextFile.getName().endsWith(".gz")) {
                            in = new BufferedReader(new InputStreamReader(
                                    new GZIPInputStream(new FileInputStream(nextFile)), Charsets.UTF_8));
                        } else {
                            in = new BufferedReader(new FileReader(nextFile));
                        }
                        return hasMore();
                    }
                    Thread.currentThread().join();
                    return false;
                } catch (IOException e) {
                    throw Throwables.propagate(e);
                } catch (InterruptedException e) {
                    throw Throwables.propagate(e);
                }
            }

            @Override
            public InputRow nextRow() {
                final InputRow retVal = parser.parse(line);
                line = null;
                return retVal;
            }

            @Override
            public Runnable commit() {
                return new Runnable() {
                    @Override
                    public void run() {

                    }
                };
            }

            @Override
            public void close() throws IOException {
                Closeables.closeQuietly(in);
            }
        };
    }
}