hbase-server/src/main/java/org/apache/hadoop/hbase/regionserver/AbstractMultiFileWriter.java

   1 /**
   2  * Licensed to the Apache Software Foundation (ASF) under one
   3  * or more contributor license agreements.  See the NOTICE file
   4  * distributed with this work for additional information
   5  * regarding copyright ownership.  The ASF licenses this file
   6  * to you under the Apache License, Version 2.0 (the
   7  * "License"); you may not use this file except in compliance
   8  * with the License.  You may obtain a copy of the License at
   9  *
  10  *     http://www.apache.org/licenses/LICENSE-2.0
  11  *
  12  * Unless required by applicable law or agreed to in writing, software
  13  * distributed under the License is distributed on an "AS IS" BASIS,
  14  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  15  * See the License for the specific language governing permissions and
  16  * limitations under the License.
  17  */
  18 package org.apache.hadoop.hbase.regionserver;
  19
  20 import java.io.IOException;
  21 import java.util.ArrayList;
  22 import java.util.Collection;
  23 import java.util.Collections;
  24 import java.util.List;
  25 import org.apache.hadoop.fs.Path;
  26 import org.apache.yetus.audience.InterfaceAudience;
  27 import org.slf4j.Logger;
  28 import org.slf4j.LoggerFactory;
  29
  30 /**
  31  * Base class for cell sink that separates the provided cells into multiple files.
  32  */
  33 @InterfaceAudience.Private
  34 public abstract class AbstractMultiFileWriter implements CellSink, ShipperListener {
  35
  36   private static final Logger LOG = LoggerFactory.getLogger(AbstractMultiFileWriter.class);
  37
  38   /** Factory that is used to produce single StoreFile.Writer-s */
  39   protected WriterFactory writerFactory;
  40
  41   /** Source scanner that is tracking KV count; may be null if source is not StoreScanner */
  42   protected StoreScanner sourceScanner;
  43
  44   public interface WriterFactory {
  45     public StoreFileWriter createWriter() throws IOException;
  46     default StoreFileWriter createWriterWithStoragePolicy(String fileStoragePolicy)
  47         throws IOException {
  48       return createWriter();
  49     };
  50   }
  51
  52   /**
  53    * Initializes multi-writer before usage.
  54    * @param sourceScanner Optional store scanner to obtain the information about read progress.
  55    * @param factory Factory used to produce individual file writers.
  56    */
  57   public void init(StoreScanner sourceScanner, WriterFactory factory) {
  58     this.writerFactory = factory;
  59     this.sourceScanner = sourceScanner;
  60   }
  61
  62   /**
  63    * Commit all writers.
  64    * <p>
  65    * Notice that here we use the same <code>maxSeqId</code> for all output files since we haven't
  66    * find an easy to find enough sequence ids for different output files in some corner cases. See
  67    * comments in HBASE-15400 for more details.
  68    */
  69   public List<Path> commitWriters(long maxSeqId, boolean majorCompaction) throws IOException {
  70     return commitWriters(maxSeqId, majorCompaction, Collections.EMPTY_SET);
  71   }
  72
  73   public List<Path> commitWriters(long maxSeqId, boolean majorCompaction,
  74       Collection<HStoreFile> storeFiles) throws IOException {
  75     preCommitWriters();
  76     Collection<StoreFileWriter> writers = this.writers();
  77     if (LOG.isDebugEnabled()) {
  78       LOG.debug(
  79           "Commit " + writers.size() + " writers, maxSeqId=" + maxSeqId + ", majorCompaction=" +
  80               majorCompaction);
  81     }
  82     List<Path> paths = new ArrayList<>();
  83     for (StoreFileWriter writer : writers) {
  84       if (writer == null) {
  85         continue;
  86       }
  87       writer.appendMetadata(maxSeqId, majorCompaction, storeFiles);
  88       preCloseWriter(writer);
  89       paths.add(writer.getPath());
  90       writer.close();
  91     }
  92     return paths;
  93   }
  94
  95   /**
  96    * Close all writers without throwing any exceptions. This is used when compaction failed usually.
  97    */
  98   public List<Path> abortWriters() {
  99     List<Path> paths = new ArrayList<>();
 100     for (StoreFileWriter writer : writers()) {
 101       try {
 102         if (writer != null) {
 103           paths.add(writer.getPath());
 104           writer.close();
 105         }
 106       } catch (Exception ex) {
 107         LOG.error("Failed to close the writer after an unfinished compaction.", ex);
 108       }
 109     }
 110     return paths;
 111   }
 112
 113   /**
 114    * Returns all writers. This is used to prevent deleting currently writen storefiles
 115    * during cleanup.
 116    */
 117   public abstract Collection<StoreFileWriter> writers();
 118
 119   /**
 120    * Subclasses override this method to be called at the end of a successful sequence of append; all
 121    * appends are processed before this method is called.
 122    */
 123   protected void preCommitWriters() throws IOException {
 124   }
 125
 126   /**
 127    * Subclasses override this method to be called before we close the give writer. Usually you can
 128    * append extra metadata to the writer.
 129    */
 130   protected void preCloseWriter(StoreFileWriter writer) throws IOException {
 131   }
 132
 133   @Override
 134   public void beforeShipped() throws IOException {
 135     Collection<StoreFileWriter> writers = writers();
 136     if (writers != null) {
 137       for (StoreFileWriter writer : writers) {
 138         if (writer != null) {
 139           writer.beforeShipped();
 140         }
 141       }
 142     }
 143   }
 144 }