| /** |
| * |
| * 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.hadoop.hbase.mapreduce; |
| |
| import java.io.IOException; |
| import java.util.HashMap; |
| import java.util.Map; |
| |
| import org.apache.commons.logging.Log; |
| import org.apache.commons.logging.LogFactory; |
| import org.apache.hadoop.hbase.classification.InterfaceAudience; |
| import org.apache.hadoop.hbase.classification.InterfaceStability; |
| import org.apache.hadoop.conf.Configuration; |
| import org.apache.hadoop.hbase.HBaseConfiguration; |
| import org.apache.hadoop.hbase.TableName; |
| import org.apache.hadoop.hbase.client.BufferedMutator; |
| import org.apache.hadoop.hbase.client.Connection; |
| import org.apache.hadoop.hbase.client.ConnectionFactory; |
| import org.apache.hadoop.hbase.client.Delete; |
| import org.apache.hadoop.hbase.client.Mutation; |
| import org.apache.hadoop.hbase.client.Put; |
| import org.apache.hadoop.hbase.client.Durability; |
| import org.apache.hadoop.hbase.io.ImmutableBytesWritable; |
| import org.apache.hadoop.hbase.util.Bytes; |
| import org.apache.hadoop.mapreduce.JobContext; |
| import org.apache.hadoop.mapreduce.OutputCommitter; |
| import org.apache.hadoop.mapreduce.OutputFormat; |
| import org.apache.hadoop.mapreduce.RecordWriter; |
| import org.apache.hadoop.mapreduce.TaskAttemptContext; |
| |
| /** |
| * <p> |
| * Hadoop output format that writes to one or more HBase tables. The key is |
| * taken to be the table name while the output value <em>must</em> be either a |
| * {@link Put} or a {@link Delete} instance. All tables must already exist, and |
| * all Puts and Deletes must reference only valid column families. |
| * </p> |
| * |
| * <p> |
| * Write-ahead logging (WAL) for Puts can be disabled by setting |
| * {@link #WAL_PROPERTY} to {@link #WAL_OFF}. Default value is {@link #WAL_ON}. |
| * Note that disabling write-ahead logging is only appropriate for jobs where |
| * loss of data due to region server failure can be tolerated (for example, |
| * because it is easy to rerun a bulk import). |
| * </p> |
| */ |
| @InterfaceAudience.Public |
| @InterfaceStability.Stable |
| public class MultiTableOutputFormat extends OutputFormat<ImmutableBytesWritable, Mutation> { |
| /** Set this to {@link #WAL_OFF} to turn off write-ahead logging (WAL) */ |
| public static final String WAL_PROPERTY = "hbase.mapreduce.multitableoutputformat.wal"; |
| /** Property value to use write-ahead logging */ |
| public static final boolean WAL_ON = true; |
| /** Property value to disable write-ahead logging */ |
| public static final boolean WAL_OFF = false; |
| /** |
| * Record writer for outputting to multiple HTables. |
| */ |
| protected static class MultiTableRecordWriter extends |
| RecordWriter<ImmutableBytesWritable, Mutation> { |
| private static final Log LOG = LogFactory.getLog(MultiTableRecordWriter.class); |
| Connection connection; |
| Map<ImmutableBytesWritable, BufferedMutator> mutatorMap = new HashMap<>(); |
| Configuration conf; |
| boolean useWriteAheadLogging; |
| |
| /** |
| * @param conf |
| * HBaseConfiguration to used |
| * @param useWriteAheadLogging |
| * whether to use write ahead logging. This can be turned off ( |
| * <tt>false</tt>) to improve performance when bulk loading data. |
| */ |
| public MultiTableRecordWriter(Configuration conf, |
| boolean useWriteAheadLogging) throws IOException { |
| LOG.debug("Created new MultiTableRecordReader with WAL " |
| + (useWriteAheadLogging ? "on" : "off")); |
| this.conf = conf; |
| this.useWriteAheadLogging = useWriteAheadLogging; |
| } |
| |
| /** |
| * @param tableName |
| * the name of the table, as a string |
| * @return the named mutator |
| * @throws IOException |
| * if there is a problem opening a table |
| */ |
| BufferedMutator getBufferedMutator(ImmutableBytesWritable tableName) throws IOException { |
| if(this.connection == null){ |
| this.connection = ConnectionFactory.createConnection(conf); |
| } |
| if (!mutatorMap.containsKey(tableName)) { |
| LOG.debug("Opening HTable \"" + Bytes.toString(tableName.get())+ "\" for writing"); |
| |
| BufferedMutator mutator = |
| connection.getBufferedMutator(TableName.valueOf(tableName.get())); |
| mutatorMap.put(tableName, mutator); |
| } |
| return mutatorMap.get(tableName); |
| } |
| |
| @Override |
| public void close(TaskAttemptContext context) throws IOException { |
| for (BufferedMutator mutator : mutatorMap.values()) { |
| mutator.close(); |
| } |
| if (connection != null) { |
| connection.close(); |
| } |
| } |
| |
| /** |
| * Writes an action (Put or Delete) to the specified table. |
| * |
| * @param tableName |
| * the table being updated. |
| * @param action |
| * the update, either a put or a delete. |
| * @throws IllegalArgumentException |
| * if the action is not a put or a delete. |
| */ |
| @Override |
| public void write(ImmutableBytesWritable tableName, Mutation action) throws IOException { |
| BufferedMutator mutator = getBufferedMutator(tableName); |
| // The actions are not immutable, so we defensively copy them |
| if (action instanceof Put) { |
| Put put = new Put((Put) action); |
| put.setDurability(useWriteAheadLogging ? Durability.SYNC_WAL |
| : Durability.SKIP_WAL); |
| mutator.mutate(put); |
| } else if (action instanceof Delete) { |
| Delete delete = new Delete((Delete) action); |
| mutator.mutate(delete); |
| } else |
| throw new IllegalArgumentException( |
| "action must be either Delete or Put"); |
| } |
| } |
| |
| @Override |
| public void checkOutputSpecs(JobContext context) throws IOException, |
| InterruptedException { |
| // we can't know ahead of time if it's going to blow up when the user |
| // passes a table name that doesn't exist, so nothing useful here. |
| } |
| |
| @Override |
| public OutputCommitter getOutputCommitter(TaskAttemptContext context) |
| throws IOException, InterruptedException { |
| return new TableOutputCommitter(); |
| } |
| |
| @Override |
| public RecordWriter<ImmutableBytesWritable, Mutation> getRecordWriter(TaskAttemptContext context) |
| throws IOException, InterruptedException { |
| Configuration conf = context.getConfiguration(); |
| return new MultiTableRecordWriter(HBaseConfiguration.create(conf), |
| conf.getBoolean(WAL_PROPERTY, WAL_ON)); |
| } |
| |
| } |