gobblin.data.management.version.finder.DateTimeDatasetVersionFinder.java Source code

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Here is the source code for gobblin.data.management.version.finder.DateTimeDatasetVersionFinder.java

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/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF 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 gobblin.data.management.version.finder;

import java.util.Properties;

import org.apache.commons.lang3.StringUtils;
import org.apache.hadoop.fs.FileStatus;
import org.apache.hadoop.fs.FileSystem;
import org.apache.hadoop.fs.Path;
import org.joda.time.DateTimeZone;
import org.joda.time.format.DateTimeFormat;
import org.joda.time.format.DateTimeFormatter;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import com.google.common.base.Preconditions;
import com.typesafe.config.Config;
import com.typesafe.config.ConfigFactory;

import gobblin.configuration.ConfigurationKeys;
import gobblin.data.management.version.FileStatusTimestampedDatasetVersion;
import gobblin.data.management.version.FileSystemDatasetVersion;
import gobblin.data.management.version.TimestampedDatasetVersion;

/**
 * {@link gobblin.data.management.version.finder.DatasetVersionFinder} for datasets based on path timestamps.
 * Uses a datetime pattern to find dataset versions from the dataset path
 * and parse the {@link org.joda.time.DateTime} representing the version.
 */
public class DateTimeDatasetVersionFinder extends AbstractDatasetVersionFinder<TimestampedDatasetVersion> {

    private static final Logger LOGGER = LoggerFactory.getLogger(DateTimeDatasetVersionFinder.class);

    /**
     * Date pattern of the partition. E.g. yyyy/MM/dd/hh/mm or yyyy/MM/dd
     */
    public static final String DATE_TIME_PATTERN_KEY = "version.datetime.pattern";
    /**
     * Time zone to be used E.g. UTC
     */
    public static final String DATE_TIME_PATTERN_TIMEZONE_KEY = "version.datetime.timezone";
    /**
     * By default the globPattern is bbtained by replacing all non-slash characters in datetime pattern by *.
     * E.g. yyyy/MM/dd/hh/mm -> *\/*\/*\/*\/*.
     * If this key is set, we use this globPatter to search for version
     */
    public static final String OPTIONAL_GLOB_PATTERN_TIMEZONE_KEY = "version.globPattern";

    public static final String DEFAULT_DATE_TIME_PATTERN_TIMEZONE = ConfigurationKeys.PST_TIMEZONE_NAME;

    private final Path globPattern;
    protected final DateTimeFormatter formatter;
    private final String datePartitionPattern;

    public DateTimeDatasetVersionFinder(FileSystem fs, Config config) {
        super(fs);
        Preconditions.checkArgument(config.hasPath(DATE_TIME_PATTERN_KEY),
                "Missing required property " + DATE_TIME_PATTERN_KEY);
        String pattern = config.getString(DATE_TIME_PATTERN_KEY);

        if (config.hasPath(OPTIONAL_GLOB_PATTERN_TIMEZONE_KEY)) {
            this.globPattern = new Path(config.getString(OPTIONAL_GLOB_PATTERN_TIMEZONE_KEY));
        } else {
            this.globPattern = new Path(pattern.replaceAll("[^/]+", "*"));
        }

        LOGGER.debug(String.format("Setting timezone for patthern: %s. By default it is %s", pattern,
                DEFAULT_DATE_TIME_PATTERN_TIMEZONE));

        if (config.hasPath(DATE_TIME_PATTERN_TIMEZONE_KEY)) {
            this.formatter = DateTimeFormat.forPattern(pattern)
                    .withZone(DateTimeZone.forID(config.getString(DATE_TIME_PATTERN_TIMEZONE_KEY)));
        } else {
            this.formatter = DateTimeFormat.forPattern(pattern)
                    .withZone(DateTimeZone.forID(DEFAULT_DATE_TIME_PATTERN_TIMEZONE));
        }

        this.datePartitionPattern = pattern;
    }

    public DateTimeDatasetVersionFinder(FileSystem fs, Properties props) {
        this(fs, ConfigFactory.parseProperties(props));
    }

    @Override
    public Class<? extends FileSystemDatasetVersion> versionClass() {
        return TimestampedDatasetVersion.class;
    }

    /**
     * Obtained by replacing all non-slash characters in datetime pattern by *.
     * E.g. yyyy/MM/dd/hh/mm -> *\/*\/*\/*\/*
     * Or glob pattern at {@value #OPTIONAL_GLOB_PATTERN_TIMEZONE_KEY} if set.
     */
    @Override
    public Path globVersionPattern() {
        return this.globPattern;
    }

    /**
     * Parse {@link org.joda.time.DateTime} from {@link org.apache.hadoop.fs.Path} using datetime pattern.
     */
    @Override
    public TimestampedDatasetVersion getDatasetVersion(Path pathRelativeToDatasetRoot,
            FileStatus versionFileStatus) {

        String dateTimeString = null;
        try {
            // pathRelativeToDatasetRoot can be daily/2016/03/02 or 2016/03/02. In either case we need to pick 2016/03/02 as version
            dateTimeString = StringUtils.substring(pathRelativeToDatasetRoot.toString(),
                    pathRelativeToDatasetRoot.toString().length() - this.datePartitionPattern.length());

            return new FileStatusTimestampedDatasetVersion(this.formatter.parseDateTime(dateTimeString),
                    versionFileStatus);

        } catch (IllegalArgumentException exception) {
            LOGGER.warn(String.format(
                    "Candidate dataset version with pathRelativeToDatasetRoot: %s has inferred dataTimeString:%s. "
                            + "It does not match expected datetime pattern %s. Ignoring.",
                    pathRelativeToDatasetRoot, dateTimeString, this.datePartitionPattern));
            return null;
        }
    }
}