io.druid.firehose.azure.StaticAzureBlobStoreFirehoseFactory.java Source code

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Here is the source code for io.druid.firehose.azure.StaticAzureBlobStoreFirehoseFactory.java

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/*
 * Druid - a distributed column store.
 * Copyright 2012 - 2015 Metamarkets Group Inc.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package io.druid.firehose.azure;

import com.fasterxml.jackson.annotation.JacksonInject;
import com.fasterxml.jackson.annotation.JsonCreator;
import com.fasterxml.jackson.annotation.JsonProperty;
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.CompressionUtils;
import com.metamx.common.logger.Logger;
import io.druid.data.input.Firehose;
import io.druid.data.input.FirehoseFactory;
import io.druid.data.input.impl.FileIteratingFirehose;
import io.druid.data.input.impl.StringInputRowParser;
import io.druid.storage.azure.AzureByteSource;
import io.druid.storage.azure.AzureStorage;
import org.apache.commons.io.IOUtils;
import org.apache.commons.io.LineIterator;

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.util.Iterator;
import java.util.LinkedList;
import java.util.List;

/**
 * This class is heavily inspired by the StaticS3FirehoseFactory class in the io.druid.firehose.s3 package
 */
public class StaticAzureBlobStoreFirehoseFactory implements FirehoseFactory<StringInputRowParser> {
    private static final Logger log = new Logger(StaticAzureBlobStoreFirehoseFactory.class);

    private final AzureStorage azureStorage;
    private final List<AzureBlob> blobs;

    @JsonCreator
    public StaticAzureBlobStoreFirehoseFactory(@JacksonInject("azureStorage") AzureStorage azureStorage,
            @JsonProperty("blobs") AzureBlob[] blobs) {
        this.azureStorage = azureStorage;
        this.blobs = ImmutableList.copyOf(blobs);
    }

    @JsonProperty
    public List<AzureBlob> getBlobs() {
        return blobs;
    }

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

        final LinkedList<AzureBlob> objectQueue = Lists.newLinkedList(blobs);

        return new FileIteratingFirehose(new Iterator<LineIterator>() {
            @Override
            public boolean hasNext() {
                return !objectQueue.isEmpty();
            }

            @Override
            public LineIterator next() {
                final AzureBlob nextURI = objectQueue.poll();

                final String container = nextURI.getContainer();
                final String path = nextURI.getPath().startsWith("/") ? nextURI.getPath().substring(1)
                        : nextURI.getPath();

                try {
                    final InputStream innerInputStream = new AzureByteSource(azureStorage, container, path)
                            .openStream();

                    final InputStream outerInputStream = path.endsWith(".gz")
                            ? CompressionUtils.gzipInputStream(innerInputStream)
                            : innerInputStream;

                    return IOUtils.lineIterator(
                            new BufferedReader(new InputStreamReader(outerInputStream, Charsets.UTF_8)));
                } catch (Exception e) {
                    log.error(e, "Exception opening container[%s] blob[%s]", container, path);

                    throw Throwables.propagate(e);
                }
            }

            @Override
            public void remove() {
                throw new UnsupportedOperationException();
            }
        }, stringInputRowParser);
    }
}