org.apache.parquet.hadoop.ParquetOutputCommitter.java Source code

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Here is the source code for org.apache.parquet.hadoop.ParquetOutputCommitter.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 org.apache.parquet.hadoop;

import java.io.IOException;
import java.util.List;

import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.fs.FileStatus;
import org.apache.hadoop.fs.FileSystem;
import org.apache.hadoop.fs.Path;
import org.apache.hadoop.mapreduce.JobContext;
import org.apache.hadoop.mapreduce.TaskAttemptContext;
import org.apache.hadoop.mapreduce.lib.output.FileOutputCommitter;

import org.apache.parquet.Log;
import org.apache.parquet.hadoop.ParquetOutputFormat.JobSummaryLevel;
import org.apache.parquet.hadoop.util.ContextUtil;

public class ParquetOutputCommitter extends FileOutputCommitter {
    private static final Log LOG = Log.getLog(ParquetOutputCommitter.class);

    private final Path outputPath;

    public ParquetOutputCommitter(Path outputPath, TaskAttemptContext context) throws IOException {
        super(outputPath, context);
        this.outputPath = outputPath;
    }

    public void commitJob(JobContext jobContext) throws IOException {
        super.commitJob(jobContext);
        Configuration configuration = ContextUtil.getConfiguration(jobContext);
        writeMetaDataFile(configuration, outputPath);
    }

    // TODO: This method should propagate errors, and we should clean up
    // TODO: all the catching of Exceptions below -- see PARQUET-383
    public static void writeMetaDataFile(Configuration configuration, Path outputPath) {
        JobSummaryLevel level = ParquetOutputFormat.getJobSummaryLevel(configuration);
        if (level == JobSummaryLevel.NONE) {
            return;
        }

        try {
            final FileSystem fileSystem = outputPath.getFileSystem(configuration);
            FileStatus outputStatus = fileSystem.getFileStatus(outputPath);
            List<Footer> footers;

            switch (level) {
            case ALL:
                footers = ParquetFileReader.readAllFootersInParallel(configuration, outputStatus, false); // don't skip row groups
                break;
            case COMMON_ONLY:
                footers = ParquetFileReader.readAllFootersInParallel(configuration, outputStatus, true); // skip row groups
                break;
            default:
                throw new IllegalArgumentException("Unrecognized job summary level: " + level);
            }

            // If there are no footers, _metadata file cannot be written since there is no way to determine schema!
            // Onus of writing any summary files lies with the caller in this case.
            if (footers.isEmpty()) {
                return;
            }

            try {
                ParquetFileWriter.writeMetadataFile(configuration, outputPath, footers, level);
            } catch (Exception e) {
                LOG.warn("could not write summary file(s) for " + outputPath, e);

                final Path metadataPath = new Path(outputPath, ParquetFileWriter.PARQUET_METADATA_FILE);

                try {
                    if (fileSystem.exists(metadataPath)) {
                        fileSystem.delete(metadataPath, true);
                    }
                } catch (Exception e2) {
                    LOG.warn("could not delete metadata file" + outputPath, e2);
                }

                try {
                    final Path commonMetadataPath = new Path(outputPath,
                            ParquetFileWriter.PARQUET_COMMON_METADATA_FILE);
                    if (fileSystem.exists(commonMetadataPath)) {
                        fileSystem.delete(commonMetadataPath, true);
                    }
                } catch (Exception e2) {
                    LOG.warn("could not delete metadata file" + outputPath, e2);
                }

            }
        } catch (Exception e) {
            LOG.warn("could not write summary file for " + outputPath, e);
        }
    }
}