flume 自定义 hbase sink 类

参考（向原作者致敬）

• http://ydt619.blog.51cto.com/316163/1230586
  
• https://blogs.apache.org/flume/entry/streaming_data_into_apache_hbase
  

flume 1.5 的配置文件示例

#Name the  components on this agenta1.sources  = r1a1.sinks =  k1a1.channels  = c1#  Describe/configure the sourcea1.sources.r1.type  = spooldira1.sources.r1.spoolDir  = /home/scut/Downloads/testFlume# Describe  the sinka1.sinks.k1.type  = org.apache.flume.sink.hbase.AsyncHBaseSinka1.sinks.k1.table = Router #设置hbase的表名a1.sinks.k1.columnFamily = log #设置hbase中的columnFamilya1.sinks.k1.serializer.payloadColumn=serviceTime,browerOS,clientTime,screenHeight,screenWidth,url,userAgent,mobileDevice,gwId,mac # 设置hbase的columna1.sinks.k1.serializer = org.apache.flume.sink.hbase.BaimiAsyncHbaseEventSerializer # 设置serializer的处理类# Use a  channel which buffers events in memorya1.channels.c1.type  = memorya1.channels.c1.capacity  = 1000a1.channels.c1.transactionCapacity  = 100# Bind the  source and sink to the channela1.sources.r1.channels  = c1a1.sinks.k1.channel  = c1

重点说明几个属性

• a1.sinks.k1.serializer.payloadColumn 中列出了所有的列名。
• a1.sinks.k1.serializer设置了flume serializer的处理类。BaimiAsyncHbaseEventSerializer类中会获取payloadColumn的内容，将它以逗号分隔，从而得出所有的列名。

BaimiAsyncHbaseEventSerializer类

/* * 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.flume.sink.hbase;import java.util.ArrayList;import java.util.List;import org.apache.flume.Context;import org.apache.flume.Event;import org.apache.flume.FlumeException;import org.hbase.async.AtomicIncrementRequest;import org.hbase.async.PutRequest;import org.apache.flume.conf.ComponentConfiguration;import org.apache.flume.sink.hbase.SimpleHbaseEventSerializer.KeyType;import com.google.common.base.Charsets;public class BaimiAsyncHbaseEventSerializer implements AsyncHbaseEventSerializer {  private byte[] table;  private byte[] cf;  private byte[][] payload;  private byte[][] payloadColumn;  private final String payloadColumnSplit = "\\^A";  private byte[] incrementColumn;  private String rowSuffix;  private String rowSuffixCol;  private byte[] incrementRow;  private KeyType keyType;  @Override  public void initialize(byte[] table, byte[] cf) {    this.table = table;    this.cf = cf;  }  @Override  public List<PutRequest> getActions() {    List<PutRequest> actions = new ArrayList<PutRequest>();    if(payloadColumn != null){      byte[] rowKey;      try {        switch (keyType) {          case TS:            rowKey = SimpleRowKeyGenerator.getTimestampKey(rowSuffix);            break;          case TSNANO:            rowKey = SimpleRowKeyGenerator.getNanoTimestampKey(rowSuffix);            break;          case RANDOM:            rowKey = SimpleRowKeyGenerator.getRandomKey(rowSuffix);            break;          default:            rowKey = SimpleRowKeyGenerator.getUUIDKey(rowSuffix);            break;        }// for 循环，提交所有列和对于数据的put请求。for (int i = 0; i < this.payload.length; i++){        PutRequest putRequest =  new PutRequest(table, rowKey, cf,payloadColumn[i], payload[i]);        actions.add(putRequest);}      } catch (Exception e){        throw new FlumeException("Could not get row key!", e);      }    }    return actions;  }  public List<AtomicIncrementRequest> getIncrements(){    List<AtomicIncrementRequest> actions = new        ArrayList<AtomicIncrementRequest>();    if(incrementColumn != null) {      AtomicIncrementRequest inc = new AtomicIncrementRequest(table,          incrementRow, cf, incrementColumn);      actions.add(inc);    }    return actions;  }  @Override  public void cleanUp() {    // TODO Auto-generated method stub  }  @Override  public void configure(Context context) {    String pCol = context.getString("payloadColumn", "pCol");    String iCol = context.getString("incrementColumn", "iCol");    rowSuffixCol = context.getString("rowPrefixCol", "mac");    String suffix = context.getString("suffix", "uuid");    if(pCol != null && !pCol.isEmpty()) {      if(suffix.equals("timestamp")){        keyType = KeyType.TS;      } else if (suffix.equals("random")) {        keyType = KeyType.RANDOM;      } else if(suffix.equals("nano")){        keyType = KeyType.TSNANO;      } else {        keyType = KeyType.UUID;      }      // 从配置文件中读出column。      String[] pCols = pCol.replace(" ", "").split(",");     payloadColumn = new byte[pCols.length][];     for (int i = 0; i < pCols.length; i++){// 列名转为小写payloadColumn[i] = pCols[i].toLowerCase().getBytes(Charsets.UTF_8);}    }    if(iCol != null && !iCol.isEmpty()) {      incrementColumn = iCol.getBytes(Charsets.UTF_8);    }    incrementRow =        context.getString("incrementRow", "incRow").getBytes(Charsets.UTF_8);  }  @Override  public void setEvent(Event event) {String strBody = new String(event.getBody());String[] subBody = strBody.split(this.payloadColumnSplit);if (subBody.length == this.payloadColumn.length){this.payload = new byte[subBody.length][];for (int i = 0; i < subBody.length; i++){this.payload[i] = subBody[i].getBytes(Charsets.UTF_8);if ((new String(this.payloadColumn[i]).equals(this.rowSuffixCol))){// rowkey 前缀是某一列的值, 默认情况是mac地址this.rowSuffix = subBody[i];}}}  }  @Override  public void configure(ComponentConfiguration conf) {    // TODO Auto-generated method stub  }}

重点可以查看setEent，configure，getActions函数。

• configure函数：读取flume配置文件内容，包括列名，rowkey后缀等信息
• setEvent函数：获取flume event 内容，将其保存到payload数组中。
• getActions函数：创建PutRequest实例，将rowkey，columnfamily,column,value等信息写入putrequest实例中。

源码编译和执行

     编写好自定义的BaimiAsyncHbaseEventSerializer函数后，接下来需要编译源码，生成flume-ng-hbase-sink.*.jar包，替换flume中原来的flume-ng-hbase-sink.*.jar包。

• 下载flume 1.5 源码，解压后进入目录flume-1.5.0-src/flume-ng-sinks/flume-ng-hbase-sinks/src/main/java/org/apache/flume/sink/hbase/
• 复制上面的BaimiAsyncHbaseEventSerializer类到上面的目录中。
• 进入flume-1.5.0-src/flume-ng-sinks/flume-ng-hbase-sinks/，运行mvn编译命令【mvn install -Dmaven.test.skip=true】
• mvn编译后会在flume-1.5.0-src/flume-ng-sinks/flume-ng-hbase-sinks/target目录下生成flume-ng-hbase-sink-1.5.0.jar,将这个jar包替换$FLUME_HOME/lib下的jar包
• 运行flume执行命令【flume-ng agent -c . -f conf/spoolDir.conf -n a1  -Dflume.root.logger=INFO,console】