com.metamx.druid.indexing.common.index.StaticS3FirehoseFactory.java Source code

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Here is the source code for com.metamx.druid.indexing.common.index.StaticS3FirehoseFactory.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 com.metamx.druid.indexing.common.index;

import com.fasterxml.jackson.annotation.JacksonInject;
import com.fasterxml.jackson.annotation.JsonCreator;
import com.fasterxml.jackson.annotation.JsonProperty;
import com.fasterxml.jackson.annotation.JsonTypeName;
import com.google.common.base.Charsets;
import com.google.common.base.Preconditions;
import com.google.common.base.Throwables;
import com.google.common.collect.ImmutableList;
import com.google.common.collect.Lists;
import com.metamx.common.logger.Logger;
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 org.apache.commons.io.IOUtils;
import org.apache.commons.io.LineIterator;

import org.jets3t.service.S3Service;
import org.jets3t.service.model.S3Object;

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.net.URI;
import java.util.List;
import java.util.NoSuchElementException;
import java.util.Queue;
import java.util.zip.GZIPInputStream;

/**
 * Builds firehoses that read from a predefined list of S3 objects and then dry up.
 */
@JsonTypeName("s3")
public class StaticS3FirehoseFactory implements FirehoseFactory {
    private final S3Service s3Client;
    private final StringInputRowParser parser;
    private final List<URI> uris;

    private final long retryCount = 5;
    private final long retryMillis = 5000;

    private static final Logger log = new Logger(StaticS3FirehoseFactory.class);

    @JsonCreator
    public StaticS3FirehoseFactory(@JacksonInject("s3Client") S3Service s3Client,
            @JsonProperty("parser") StringInputRowParser parser, @JsonProperty("uris") List<URI> uris) {
        this.s3Client = s3Client;
        this.parser = Preconditions.checkNotNull(parser, "parser");
        this.uris = ImmutableList.copyOf(uris);

        for (final URI inputURI : uris) {
            Preconditions.checkArgument(inputURI.getScheme().equals("s3"), "input uri scheme == s3 (%s)", inputURI);
        }
    }

    @JsonProperty
    public StringInputRowParser getParser() {
        return parser;
    }

    @JsonProperty
    public List<URI> getUris() {
        return uris;
    }

    @Override
    public Firehose connect() throws IOException {
        Preconditions.checkNotNull(s3Client, "null s3Client");

        return new Firehose() {
            LineIterator lineIterator = null;
            final Queue<URI> objectQueue = Lists.newLinkedList(uris);

            // Rolls over our streams and iterators to the next file, if appropriate
            private void maybeNextFile() throws Exception {

                if (lineIterator == null || !lineIterator.hasNext()) {

                    // Close old streams, maybe.
                    if (lineIterator != null) {
                        lineIterator.close();
                    }

                    // Open new streams, maybe.
                    final URI nextURI = objectQueue.poll();
                    if (nextURI != null) {

                        final String s3Bucket = nextURI.getAuthority();
                        final S3Object s3Object = new S3Object(
                                nextURI.getPath().startsWith("/") ? nextURI.getPath().substring(1)
                                        : nextURI.getPath());

                        log.info("Reading from bucket[%s] object[%s] (%s)", s3Bucket, s3Object.getKey(), nextURI);

                        int ntry = 0;
                        try {
                            final InputStream innerInputStream = s3Client.getObject(s3Bucket, s3Object.getKey())
                                    .getDataInputStream();

                            final InputStream outerInputStream = s3Object.getKey().endsWith(".gz")
                                    ? new GZIPInputStream(innerInputStream)
                                    : innerInputStream;

                            lineIterator = IOUtils.lineIterator(
                                    new BufferedReader(new InputStreamReader(outerInputStream, Charsets.UTF_8)));
                        } catch (IOException e) {
                            log.error(e,
                                    "Exception reading from bucket[%s] object[%s] (try %d) (sleeping %d millis)",
                                    s3Bucket, s3Object.getKey(), ntry, retryMillis);

                            ntry++;
                            if (ntry <= retryCount) {
                                Thread.sleep(retryMillis);
                            }
                        }

                    }
                }

            }

            @Override
            public boolean hasMore() {
                try {
                    maybeNextFile();
                } catch (Exception e) {
                    throw Throwables.propagate(e);
                }

                return lineIterator != null && lineIterator.hasNext();
            }

            @Override
            public InputRow nextRow() {
                try {
                    maybeNextFile();
                } catch (Exception e) {
                    throw Throwables.propagate(e);
                }

                if (lineIterator == null) {
                    throw new NoSuchElementException();
                }

                return parser.parse(lineIterator.next());
            }

            @Override
            public Runnable commit() {
                // Do nothing.
                return new Runnable() {
                    public void run() {
                    }
                };
            }

            @Override
            public void close() throws IOException {
                objectQueue.clear();
                if (lineIterator != null) {
                    lineIterator.close();
                }
            }
        };
    }
}