/*
*
* 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.coprocessor;
import java.io.IOException;
import java.util.ArrayList;
import java.util.List;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.apache.hadoop.hbase.Coprocessor;
import org.apache.hadoop.hbase.CoprocessorEnvironment;
import org.apache.hadoop.hbase.KeyValue;
import org.apache.hadoop.hbase.client.Scan;
import org.apache.hadoop.hbase.coprocessor.protobuf.generated.ColumnAggregationProtos.ColumnAggregationService;
import org.apache.hadoop.hbase.coprocessor.protobuf.generated.ColumnAggregationProtos.SumRequest;
import org.apache.hadoop.hbase.coprocessor.protobuf.generated.ColumnAggregationProtos.SumResponse;
import org.apache.hadoop.hbase.exceptions.CoprocessorException;
import org.apache.hadoop.hbase.protobuf.ResponseConverter;
import org.apache.hadoop.hbase.regionserver.InternalScanner;
import org.apache.hadoop.hbase.util.Bytes;
import com.google.protobuf.RpcCallback;
import com.google.protobuf.RpcController;
import com.google.protobuf.Service;
/**
* The aggregation implementation at a region.
*/
public class ColumnAggregationEndpoint extends ColumnAggregationService
implements Coprocessor, CoprocessorService {
static final Log LOG = LogFactory.getLog(ColumnAggregationEndpoint.class);
private RegionCoprocessorEnvironment env = null;
@Override
public Service getService() {
return this;
}
@Override
public void start(CoprocessorEnvironment env) throws IOException {
if (env instanceof RegionCoprocessorEnvironment) {
this.env = (RegionCoprocessorEnvironment)env;
return;
}
throw new CoprocessorException("Must be loaded on a table region!");
}
@Override
public void stop(CoprocessorEnvironment env) throws IOException {
// Nothing to do.
}
@Override
public void sum(RpcController controller, SumRequest request, RpcCallback<SumResponse> done) {
// aggregate at each region
Scan scan = new Scan();
// Family is required in pb. Qualifier is not.
byte [] family = request.getFamily().toByteArray();
byte [] qualifier = request.hasQualifier()? request.getQualifier().toByteArray(): null;
if (request.hasQualifier()) {
scan.addColumn(family, qualifier);
} else {
scan.addFamily(family);
}
int sumResult = 0;
InternalScanner scanner = null;
try {
scanner = this.env.getRegion().getScanner(scan);
List<KeyValue> curVals = new ArrayList<KeyValue>();
boolean hasMore = false;
do {
curVals.clear();
hasMore = scanner.next(curVals);
for (KeyValue kv : curVals) {
if (Bytes.equals(qualifier, kv.getQualifier())) {
sumResult += Bytes.toInt(kv.getBuffer(), kv.getValueOffset());
}
}
} while (hasMore);
} catch (IOException e) {
ResponseConverter.setControllerException(controller, e);
// Set result to -1 to indicate error.
sumResult = -1;
LOG.info("Setting sum result to -1 to indicate error", e);
} finally {
if (scanner != null) {
try {
scanner.close();
} catch (IOException e) {
ResponseConverter.setControllerException(controller, e);
sumResult = -1;
LOG.info("Setting sum result to -1 to indicate error", e);
}
}
}
done.run(SumResponse.newBuilder().setSum(sumResult).build());
}
}