org.apache.hudi.common.table.log.LogReaderUtils Maven / Gradle / Ivy
/*
* 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.hudi.common.table.log;
import org.apache.hudi.common.fs.FSUtils;
import org.apache.hudi.common.model.HoodieLogFile;
import org.apache.hudi.common.table.HoodieTableMetaClient;
import org.apache.hudi.common.table.log.HoodieLogFormat.Reader;
import org.apache.hudi.common.table.log.block.HoodieDataBlock;
import org.apache.hudi.common.table.log.block.HoodieLogBlock;
import org.apache.hudi.common.table.log.block.HoodieLogBlock.HeaderMetadataType;
import org.apache.hudi.common.table.timeline.HoodieActiveTimeline;
import org.apache.hudi.common.table.timeline.HoodieTimeline;
import org.apache.hudi.common.util.Base64CodecUtil;
import org.apache.hudi.common.util.collection.Pair;
import org.apache.avro.Schema;
import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.fs.FileSystem;
import org.roaringbitmap.longlong.Roaring64NavigableMap;
import java.io.ByteArrayInputStream;
import java.io.ByteArrayOutputStream;
import java.io.DataInputStream;
import java.io.DataOutputStream;
import java.io.IOException;
import java.util.List;
import java.util.Map;
import java.util.stream.Collectors;
/**
* Utils class for performing various log file reading operations.
*/
public class LogReaderUtils {
private static Schema readSchemaFromLogFileInReverse(FileSystem fs, HoodieActiveTimeline activeTimeline, HoodieLogFile hoodieLogFile)
throws IOException {
// set length for the HoodieLogFile as it will be leveraged by HoodieLogFormat.Reader with reverseReading enabled
Reader reader = HoodieLogFormat.newReader(fs, hoodieLogFile, null, true, true);
Schema writerSchema = null;
HoodieTimeline completedTimeline = activeTimeline.getCommitsTimeline().filterCompletedInstants();
while (reader.hasPrev()) {
HoodieLogBlock block = reader.prev();
if (block instanceof HoodieDataBlock) {
HoodieDataBlock lastBlock = (HoodieDataBlock) block;
if (completedTimeline
.containsOrBeforeTimelineStarts(lastBlock.getLogBlockHeader().get(HeaderMetadataType.INSTANT_TIME))) {
writerSchema = new Schema.Parser().parse(lastBlock.getLogBlockHeader().get(HeaderMetadataType.SCHEMA));
break;
}
}
}
reader.close();
return writerSchema;
}
public static Schema readLatestSchemaFromLogFiles(String basePath, List logFiles, Configuration config)
throws IOException {
HoodieTableMetaClient metaClient = HoodieTableMetaClient.builder().setConf(config).setBasePath(basePath).build();
List deltaPaths = logFiles.stream().sorted(HoodieLogFile.getReverseLogFileComparator()).map(s -> s.getPath().toString())
.collect(Collectors.toList());
if (deltaPaths.size() > 0) {
Map deltaFilePathToFileStatus = logFiles.stream().map(entry -> Pair.of(entry.getPath().toString(), entry))
.collect(Collectors.toMap(Pair::getKey, Pair::getValue));
for (String logPath : deltaPaths) {
FileSystem fs = FSUtils.getFs(logPath, config);
Schema schemaFromLogFile = readSchemaFromLogFileInReverse(fs, metaClient.getActiveTimeline(), deltaFilePathToFileStatus.get(logPath));
if (schemaFromLogFile != null) {
return schemaFromLogFile;
}
}
}
return null;
}
/**
* Encodes a list of record positions in long type.
*
* The encoding applies the Base64 codec ({@link java.util.Base64} in Java implementation) on
* the bytes generated from serializing {@link Roaring64NavigableMap} bitmap, which contains
* the list of record positions in long type, using the portable
* format.
*
* @param positions A list of long-typed positions.
* @return A string of Base64-encoded bytes ({@link java.util.Base64} in Java implementation)
* generated from serializing {@link Roaring64NavigableMap} bitmap using the portable format.
* @throws IOException upon I/O error.
*/
public static String encodePositions(List positions) throws IOException {
Roaring64NavigableMap positionBitmap = new Roaring64NavigableMap();
positions.forEach(positionBitmap::add);
return encodePositions(positionBitmap);
}
/**
* Encodes the {@link Roaring64NavigableMap} bitmap containing the record positions.
*
* The encoding applies the Base64 codec ({@link java.util.Base64} in Java implementation) on
* the bytes generated from serializing {@link Roaring64NavigableMap} bitmap using the portable
* format.
*
* @param positionBitmap {@link Roaring64NavigableMap} bitmap containing the record positions.
* @return A string of Base64-encoded bytes ({@link java.util.Base64} in Java implementation)
* generated from serializing {@link Roaring64NavigableMap} bitmap using the portable format.
* @throws IOException upon I/O error.
*/
public static String encodePositions(Roaring64NavigableMap positionBitmap) throws IOException {
positionBitmap.runOptimize();
ByteArrayOutputStream baos = new ByteArrayOutputStream();
DataOutputStream dos = new DataOutputStream(baos);
positionBitmap.serializePortable(dos);
return Base64CodecUtil.encode(baos.toByteArray());
}
/**
* Decodes the {@link HeaderMetadataType#RECORD_POSITIONS} block header into record positions.
*
* @param content A string of Base64-encoded bytes ({@link java.util.Base64} in Java
* implementation) generated from serializing {@link Roaring64NavigableMap}
* bitmap using the portable format.
* @return A {@link Roaring64NavigableMap} bitmap containing the record positions in long type.
* @throws IOException upon I/O error.
*/
public static Roaring64NavigableMap decodeRecordPositionsHeader(String content) throws IOException {
Roaring64NavigableMap positionBitmap = new Roaring64NavigableMap();
ByteArrayInputStream bais = new ByteArrayInputStream(Base64CodecUtil.decode(content));
DataInputStream dis = new DataInputStream(bais);
positionBitmap.deserializePortable(dis);
return positionBitmap;
}
}