HADOOP-8367 Improve documentation of declaringClassProtocolName in rpc headers (Sanjay Radia)

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/trunk@1342051 13f79535-47bb-0310-9956-ffa450edef68
This commit is contained in:
Sanjay Radia 2012-05-23 21:16:39 +00:00
parent 74dfa8f1f2
commit 266a0f1de9
3 changed files with 45 additions and 8 deletions

View File

@ -70,6 +70,9 @@ Trunk (unreleased changes)
HADOOP-8360. empty-configuration.xml fails xml validation
(Radim Kolar via harsh)
HADOOP-8367 Improve documentation of declaringClassProtocolName in rpc headers
(Sanjay Radia)
BUG FIXES
HADOOP-8177. MBeans shouldn't try to register when it fails to create MBeanName.

View File

@ -396,24 +396,44 @@ public class ProtobufRpcEngine implements RpcEngine {
* it is.</li>
* </ol>
*/
public Writable call(RPC.Server server, String protocol,
public Writable call(RPC.Server server, String connectionProtocolName,
Writable writableRequest, long receiveTime) throws Exception {
RpcRequestWritable request = (RpcRequestWritable) writableRequest;
HadoopRpcRequestProto rpcRequest = request.message;
String methodName = rpcRequest.getMethodName();
String protoName = rpcRequest.getDeclaringClassProtocolName();
/**
* RPCs for a particular interface (ie protocol) are done using a
* IPC connection that is setup using rpcProxy.
* The rpcProxy's has a declared protocol name that is
* sent form client to server at connection time.
*
* Each Rpc call also sends a protocol name
* (called declaringClassprotocolName). This name is usually the same
* as the connection protocol name except in some cases.
* For example metaProtocols such ProtocolInfoProto which get info
* about the protocol reuse the connection but need to indicate that
* the actual protocol is different (i.e. the protocol is
* ProtocolInfoProto) since they reuse the connection; in this case
* the declaringClassProtocolName field is set to the ProtocolInfoProto.
*/
String declaringClassProtoName =
rpcRequest.getDeclaringClassProtocolName();
long clientVersion = rpcRequest.getClientProtocolVersion();
if (server.verbose)
LOG.info("Call: protocol=" + protocol + ", method=" + methodName);
LOG.info("Call: connectionProtocolName=" + connectionProtocolName +
", method=" + methodName);
ProtoClassProtoImpl protocolImpl = getProtocolImpl(server, protoName,
clientVersion);
ProtoClassProtoImpl protocolImpl = getProtocolImpl(server,
declaringClassProtoName, clientVersion);
BlockingService service = (BlockingService) protocolImpl.protocolImpl;
MethodDescriptor methodDescriptor = service.getDescriptorForType()
.findMethodByName(methodName);
if (methodDescriptor == null) {
String msg = "Unknown method " + methodName + " called on " + protocol
+ " protocol.";
String msg = "Unknown method " + methodName + " called on "
+ connectionProtocolName + " protocol.";
LOG.warn(msg);
throw new RpcServerException(msg);
}

View File

@ -38,7 +38,21 @@ message HadoopRpcRequestProto {
/** Bytes corresponding to the client protobuf request */
optional bytes request = 2;
/** protocol name of class declaring the called method */
/**
* RPCs for a particular interface (ie protocol) are done using a
* IPC connection that is setup using rpcProxy.
* The rpcProxy's has a declared protocol name that is
* sent form client to server at connection time.
*
* Each Rpc call also sends a protocol name
* (called declaringClassprotocolName). This name is usually the same
* as the connection protocol name except in some cases.
* For example metaProtocols such ProtocolInfoProto which get metainfo
* about the protocol reuse the connection but need to indicate that
* the actual protocol is different (i.e. the protocol is
* ProtocolInfoProto) since they reuse the connection; in this case
* the declaringClassProtocolName field is set to the ProtocolInfoProto
*/
required string declaringClassProtocolName = 3;
/** protocol version of class declaring the called method */