/*
* Copyright 2008-2013 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 voldemort.server.protocol.admin;
import java.io.DataInputStream;
import java.io.DataOutputStream;
import java.io.IOException;
import voldemort.client.protocol.pb.ProtoUtils;
import voldemort.client.protocol.pb.VAdminProto;
import voldemort.client.protocol.pb.VAdminProto.FetchPartitionEntriesRequest;
import voldemort.routing.StoreRoutingPlan;
import voldemort.server.StoreRepository;
import voldemort.server.VoldemortConfig;
import voldemort.store.ErrorCodeMapper;
import voldemort.store.metadata.MetadataStore;
import voldemort.store.stats.StreamingStats.Operation;
import voldemort.utils.ByteArray;
import voldemort.utils.ClosableIterator;
import voldemort.utils.NetworkClassLoader;
import voldemort.utils.Pair;
import voldemort.versioning.Versioned;
import com.google.protobuf.Message;
/**
* Fetches entries using an efficient partition scan. Of course, only works if
* isPartitionScanSupported() is true for the storage engine to be scanned..
*
*/
public class PartitionScanFetchEntriesRequestHandler extends PartitionScanFetchStreamRequestHandler {
protected ClosableIterator<Pair<ByteArray, Versioned<byte[]>>> entriesPartitionIterator;
public PartitionScanFetchEntriesRequestHandler(FetchPartitionEntriesRequest request,
MetadataStore metadataStore,
ErrorCodeMapper errorCodeMapper,
VoldemortConfig voldemortConfig,
StoreRepository storeRepository,
NetworkClassLoader networkClassLoader) {
super(request,
metadataStore,
errorCodeMapper,
voldemortConfig,
storeRepository,
networkClassLoader,
Operation.FETCH_ENTRIES);
logger.info("Starting fetch entries for store '" + storageEngine.getName()
+ "' with partitions " + partitionList);
entriesPartitionIterator = null;
}
@Override
public StreamRequestHandlerState handleRequest(DataInputStream inputStream,
DataOutputStream outputStream)
throws IOException {
// process the next partition
if(entriesPartitionIterator == null) {
if(currentIndex == partitionList.size()) {
return StreamRequestHandlerState.COMPLETE;
}
// find the next partition to scan
boolean found = false;
while(!found && (currentIndex < partitionList.size())) {
currentPartition = new Integer(partitionList.get(currentIndex));
// Check the current node contains the partition
if(!fetchedPartitions.contains(currentPartition)
&& StoreRoutingPlan.checkPartitionBelongsToNode(currentPartition,
nodeId,
initialCluster,
storeDef)) {
found = true;
completedFetchingCurrentPartition();
entriesPartitionIterator = storageEngine.entries(currentPartition);
statusInfoMessage("Starting fetch entries");
}
currentIndex++;
}
} else {
long startNs = System.nanoTime();
// do a check before reading in case partition has 0 elements
if(entriesPartitionIterator.hasNext()) {
Pair<ByteArray, Versioned<byte[]>> entry = entriesPartitionIterator.next();
ByteArray key = entry.getFirst();
Versioned<byte[]> value = entry.getSecond();
reportStorageOpTime(startNs);
throttler.maybeThrottle(key.length());
if(filter.accept(key, value)) {
recordFetched();
VAdminProto.FetchPartitionEntriesResponse.Builder response = VAdminProto.FetchPartitionEntriesResponse.newBuilder();
VAdminProto.PartitionEntry partitionEntry = VAdminProto.PartitionEntry.newBuilder()
.setKey(ProtoUtils.encodeBytes(key))
.setVersioned(ProtoUtils.encodeVersioned(value))
.build();
response.setPartitionEntry(partitionEntry);
Message message = response.build();
sendMessage(outputStream, message);
throttler.maybeThrottle(AdminServiceRequestHandler.valueSize(value));
}
accountForScanProgress("entries");
}
if(!entriesPartitionIterator.hasNext() || fetchedEnoughForCurrentPartition()) {
// Finished current partition. Reset iterator. Info status.
entriesPartitionIterator.close();
entriesPartitionIterator = null;
statusInfoMessage("Finished fetch keys");
progressInfoMessage("Fetch entries (end of partition)");
}
}
return StreamRequestHandlerState.WRITING;
}
@Override
public final void close(DataOutputStream outputStream) throws IOException {
if(null != entriesPartitionIterator)
entriesPartitionIterator.close();
super.close(outputStream);
}
}