io.druid.storage.s3.S3TimestampVersionedDataFinder.java Source code

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Here is the source code for io.druid.storage.s3.S3TimestampVersionedDataFinder.java

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/*
 * Licensed to Metamarkets Group Inc. (Metamarkets) under one
 * or more contributor license agreements. See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership. Metamarkets licenses this file
 * to you 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.storage.s3;

import com.amazonaws.services.s3.AmazonS3;
import com.amazonaws.services.s3.model.S3ObjectSummary;
import com.google.common.base.Throwables;
import com.google.inject.Inject;
import io.druid.data.SearchableVersionedDataFinder;
import io.druid.java.util.common.RetryUtils;
import io.druid.java.util.common.StringUtils;

import javax.annotation.Nullable;
import java.net.URI;
import java.util.Iterator;
import java.util.regex.Pattern;

/**
 * This is implemented explicitly for URIExtractionNamespaceFunctionFactory
 * If you have a use case for this interface beyond URIExtractionNamespaceFunctionFactory please bring it up in the dev list.
 */
public class S3TimestampVersionedDataFinder extends S3DataSegmentPuller
        implements SearchableVersionedDataFinder<URI> {
    private static final int MAX_LISTING_KEYS = 1000;

    @Inject
    public S3TimestampVersionedDataFinder(AmazonS3 s3Client) {
        super(s3Client);
    }

    /**
     * Gets the key with the most recently modified timestamp.
     * `pattern` is evaluated against the entire key AFTER the path given in `uri`.
     * The substring `pattern` is matched against will have a leading `/` removed.
     * For example `s3://some_bucket/some_prefix/some_key` with a URI of `s3://some_bucket/some_prefix` will match against `some_key`.
     * `s3://some_bucket/some_prefixsome_key` with a URI of `s3://some_bucket/some_prefix` will match against `some_key`
     * `s3://some_bucket/some_prefix//some_key` with a URI of `s3://some_bucket/some_prefix` will match against `/some_key`
     *
     * @param uri     The URI of in the form of `s3://some_bucket/some_key`
     * @param pattern The pattern matcher to determine if a *key* is of interest, or `null` to match everything.
     *
     * @return A URI to the most recently modified object which matched the pattern.
     */
    @Override
    public URI getLatestVersion(final URI uri, final @Nullable Pattern pattern) {
        try {
            return RetryUtils.retry(() -> {
                final S3Coords coords = new S3Coords(checkURI(uri));
                long mostRecent = Long.MIN_VALUE;
                URI latest = null;
                final Iterator<S3ObjectSummary> objectSummaryIterator = S3Utils.objectSummaryIterator(s3Client,
                        coords.bucket, coords.path, MAX_LISTING_KEYS);
                while (objectSummaryIterator.hasNext()) {
                    final S3ObjectSummary objectSummary = objectSummaryIterator.next();
                    String keyString = objectSummary.getKey().substring(coords.path.length());
                    if (keyString.startsWith("/")) {
                        keyString = keyString.substring(1);
                    }
                    if (pattern != null && !pattern.matcher(keyString).matches()) {
                        continue;
                    }
                    final long latestModified = objectSummary.getLastModified().getTime();
                    if (latestModified >= mostRecent) {
                        mostRecent = latestModified;
                        latest = new URI(StringUtils.format("s3://%s/%s", objectSummary.getBucketName(),
                                objectSummary.getKey()));
                    }
                }
                return latest;
            }, shouldRetryPredicate(), DEFAULT_RETRY_COUNT);
        } catch (Exception e) {
            throw Throwables.propagate(e);
        }
    }

}