/*
* Copyright (c) 2010-2012 LinkedIn, Inc
*
* Licensed 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 krati.store.bus.protocol;
import java.util.HashMap;
import java.util.Map;
import org.apache.avro.generic.GenericRecord;
import krati.io.Serializer;
import krati.retention.Event;
import krati.retention.Position;
import krati.retention.SimpleEvent;
import krati.retention.SimplePosition;
import krati.retention.clock.Clock;
import krati.store.avro.protocol.ProtocolConstants;
import krati.store.bus.AvroStoreBus;
/**
* AvroStoreBusProtocolHandler
*
* @author jwu
* @since 10/04, 2011
*/
public class AvroStoreBusProtocolHandler<K> implements StoreBusProtocolHandler {
protected final AvroStoreBus<K> _storeBus;
protected final Serializer<K> _keySerializer;
protected final Serializer<GenericRecord> _valueSerializer;
public AvroStoreBusProtocolHandler(AvroStoreBus<K> storeBus) {
this._storeBus = storeBus;
this._keySerializer = storeBus.getStore().getKeySerializer();
this._valueSerializer = storeBus.getStore().getValueSerializer();
}
@Override
public byte[] get(byte[] key) throws Exception {
K storeKey = _keySerializer.deserialize(key);
GenericRecord storeValue = _storeBus.get(storeKey);
return storeValue == null ? null : _valueSerializer.serialize(storeValue);
}
@Override
public Position getPosition() {
return _storeBus.getPosition();
}
@Override
public Position getPosition(Clock clock) {
return _storeBus.getPosition(clock);
}
@Override
public Position getPosition(String positionStr) {
return SimplePosition.parsePosition(positionStr);
}
@Override
public String meta(String opt, String key, String value) throws Exception {
StoreBusDirective directive = StoreBusDirective.valueOf(opt);
if(directive == StoreBusDirective.Position) {
if(key == null) {
return getPosition().toString();
} else {
Clock clock = Clock.parseClock(key);
return getPosition(clock).toString();
}
}
// no-operation
return ProtocolConstants.NOP;
}
@Override
public Position syncUp(Position position, Map<byte[], Event<byte[]>> map) {
Map<K, Event<GenericRecord>> inputMap = new HashMap<K, Event<GenericRecord>>();
Position nextPosition = _storeBus.get(position, inputMap);
for(Map.Entry<K, Event<GenericRecord>> e : inputMap.entrySet()) {
byte[] key = _keySerializer.serialize(e.getKey());
GenericRecord record = e.getValue().getValue();
byte[] value = record == null ? null : _valueSerializer.serialize(record);
map.put(key, new SimpleEvent<byte[]>(value, e.getValue().getClock()));
}
return nextPosition;
}
}