/*
* 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.ipc;
import java.io.IOException;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.apache.hadoop.classification.InterfaceAudience;
import org.apache.hadoop.hbase.HConstants;
import org.apache.hadoop.hbase.client.HConnection;
import org.apache.hadoop.hbase.protobuf.ProtobufUtil;
import org.apache.hadoop.hbase.protobuf.generated.ClientProtos;
import org.apache.hadoop.hbase.protobuf.generated.ClientProtos.CoprocessorServiceResponse;
import com.google.protobuf.ByteString;
import com.google.protobuf.Descriptors;
import com.google.protobuf.Message;
/**
* Provides clients with an RPC connection to call coprocessor endpoint {@link com.google.protobuf.Service}s
* against the active master. An instance of this class may be obtained
* by calling {@link org.apache.hadoop.hbase.client.HBaseAdmin#coprocessorService()},
* but should normally only be used in creating a new {@link com.google.protobuf.Service} stub to call the endpoint
* methods.
* @see org.apache.hadoop.hbase.client.HBaseAdmin#coprocessorService()
*/
@InterfaceAudience.Private
public class MasterCoprocessorRpcChannel extends CoprocessorRpcChannel{
private static Log LOG = LogFactory.getLog(MasterCoprocessorRpcChannel.class);
private final HConnection connection;
public MasterCoprocessorRpcChannel(HConnection conn) {
this.connection = conn;
}
@Override
protected Message callExecService(Descriptors.MethodDescriptor method,
Message request, Message responsePrototype)
throws IOException {
if (LOG.isDebugEnabled()) {
LOG.debug("Call: "+method.getName()+", "+request.toString());
}
final ClientProtos.CoprocessorServiceCall call =
ClientProtos.CoprocessorServiceCall.newBuilder()
.setRow(ByteString.copyFrom(HConstants.EMPTY_BYTE_ARRAY))
.setServiceName(method.getService().getFullName())
.setMethodName(method.getName())
.setRequest(request.toByteString()).build();
CoprocessorServiceResponse result = ProtobufUtil.execService(connection.getMasterAdmin(), call);
Message response = null;
if (result.getValue().hasValue()) {
response = responsePrototype.newBuilderForType()
.mergeFrom(result.getValue().getValue()).build();
} else {
response = responsePrototype.getDefaultInstanceForType();
}
if (LOG.isTraceEnabled()) {
LOG.trace("Master Result is value=" + response);
}
return response;
}
}