/**
* 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.storm.hbase.bolt;
import backtype.storm.topology.OutputFieldsDeclarer;
import backtype.storm.tuple.Tuple;
import backtype.storm.tuple.Values;
import com.google.common.collect.Lists;
import org.apache.commons.lang.Validate;
import org.apache.hadoop.hbase.client.Get;
import org.apache.hadoop.hbase.client.Result;
import org.apache.storm.hbase.bolt.mapper.HBaseMapper;
import org.apache.storm.hbase.bolt.mapper.HBaseProjectionCriteria;
import org.apache.storm.hbase.bolt.mapper.HBaseValueMapper;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
/**
* Basic bolt for querying from HBase.
*
* Note: Each HBaseBolt defined in a topology is tied to a specific table.
*
*/
public class HBaseLookupBolt extends AbstractHBaseBolt {
private static final Logger LOG = LoggerFactory.getLogger(HBaseLookupBolt.class);
private HBaseValueMapper rowToTupleMapper;
private HBaseProjectionCriteria projectionCriteria;
public HBaseLookupBolt(String tableName, HBaseMapper mapper, HBaseValueMapper rowToTupleMapper){
super(tableName, mapper);
Validate.notNull(rowToTupleMapper, "rowToTupleMapper can not be null");
this.rowToTupleMapper = rowToTupleMapper;
}
public HBaseLookupBolt withConfigKey(String configKey){
this.configKey = configKey;
return this;
}
public HBaseLookupBolt withProjectionCriteria(HBaseProjectionCriteria projectionCriteria) {
this.projectionCriteria = projectionCriteria;
return this;
}
@Override
public void execute(Tuple tuple) {
byte[] rowKey = this.mapper.rowKey(tuple);
Get get = hBaseClient.constructGetRequests(rowKey, projectionCriteria);
try {
Result result = hBaseClient.batchGet(Lists.newArrayList(get))[0];
for(Values values : rowToTupleMapper.toValues(tuple, result)) {
this.collector.emit(values);
}
this.collector.ack(tuple);
} catch (Exception e) {
LOG.warn("Could not perform Lookup for rowKey =" + rowKey + " from Hbase.", e);
this.collector.fail(tuple);
}
}
@Override
public void declareOutputFields(OutputFieldsDeclarer outputFieldsDeclarer) {
rowToTupleMapper.declareOutputFields(outputFieldsDeclarer);
}
}