com.uber.hoodie.HoodieDataSourceHelpers.java Source code

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Here is the source code for com.uber.hoodie.HoodieDataSourceHelpers.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 com.uber.hoodie;

import com.google.common.collect.Sets;
import com.uber.hoodie.common.model.HoodieTableType;
import com.uber.hoodie.common.table.HoodieTableMetaClient;
import com.uber.hoodie.common.table.HoodieTimeline;
import com.uber.hoodie.common.table.timeline.HoodieActiveTimeline;
import com.uber.hoodie.common.table.timeline.HoodieInstant;
import java.util.List;
import java.util.stream.Collectors;
import org.apache.hadoop.fs.FileSystem;

/**
 * List of helpers to aid, construction of instanttime for read and write operations using
 * datasource
 */
public class HoodieDataSourceHelpers {

    /**
     * Checks if the Hoodie dataset has new data since given timestamp. This can be subsequently fed
     * to an incremental view read, to perform incremental processing.
     */
    public static boolean hasNewCommits(FileSystem fs, String basePath, String commitTimestamp) {
        return listCommitsSince(fs, basePath, commitTimestamp).size() > 0;
    }

    /**
     * Get a list of instant times that have occurred, from the given instant timestamp.
     */
    public static List<String> listCommitsSince(FileSystem fs, String basePath, String instantTimestamp) {
        HoodieTimeline timeline = allCompletedCommitsCompactions(fs, basePath);
        return timeline.findInstantsAfter(instantTimestamp, Integer.MAX_VALUE).getInstants()
                .map(HoodieInstant::getTimestamp).collect(Collectors.toList());
    }

    /**
     * Returns the last successful write operation's instant time
     */
    public static String latestCommit(FileSystem fs, String basePath) {
        HoodieTimeline timeline = allCompletedCommitsCompactions(fs, basePath);
        return timeline.lastInstant().get().getTimestamp();
    }

    /**
     * Obtain all the commits, compactions that have occurred on the timeline, whose instant times
     * could be fed into the datasource options.
     */
    public static HoodieTimeline allCompletedCommitsCompactions(FileSystem fs, String basePath) {
        HoodieTableMetaClient metaClient = new HoodieTableMetaClient(fs.getConf(), basePath, true);
        if (metaClient.getTableType().equals(HoodieTableType.MERGE_ON_READ)) {
            return metaClient.getActiveTimeline().getTimelineOfActions(
                    Sets.newHashSet(HoodieActiveTimeline.COMMIT_ACTION, HoodieActiveTimeline.DELTA_COMMIT_ACTION));
        } else {
            return metaClient.getCommitTimeline().filterCompletedInstants();
        }
    }
}