LogCabin::Client::LeaderRPCBase::Call Class Reference

An asynchronous version of call(). More...

#include <LeaderRPC.h>

Inheritance diagram for LogCabin::Client::LeaderRPCBase::Call:

List of all members.

Public Types
enum	Status {   OK,   RETRY,   TIMEOUT,   INVALID_REQUEST }
	Return type for LeaderRPCBase::Call::wait(). More...
Public Member Functions
	Call ()
	Constructor.
virtual	~Call ()
	Destructor.
virtual void	start (OpCode opCode, const google::protobuf::Message &request, TimePoint timeout)=0
	Invoke the RPC.
virtual void	cancel ()=0
	Cancel the RPC.
virtual Status	wait (google::protobuf::Message &response, TimePoint timeout)=0
	Wait for the RPC to complete.
Friends
std::ostream &	operator<< (std::ostream &os, const Status &server)
	Print out a Status for debugging purposes.

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Detailed Description

An asynchronous version of call().

This allows multiple RPCs to be executed concurrently, or canceling an RPC that is running on a separate thread.

Definition at line 129 of file LeaderRPC.h.

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Member Enumeration Documentation

enum LogCabin::Client::LeaderRPCBase::Call::Status

Return type for LeaderRPCBase::Call::wait().

Enumerator:

OK	The RPC completed scucessfully.
RETRY	The RPC did not succeed, nor did it timeout. The caller should try again. TODO(ongaro): this is a bit ugly
TIMEOUT	The given timeout elapsed before the RPC completed.
INVALID_REQUEST	The server rejected the request, probably because it doesn't support the opcode, or maybe the request arguments were invalid.

Definition at line 134 of file LeaderRPC.h.

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Constructor & Destructor Documentation

LogCabin::Client::LeaderRPCBase::Call::Call

(

)

[inline]

Constructor.

Definition at line 165 of file LeaderRPC.h.

virtual LogCabin::Client::LeaderRPCBase::Call::~Call

(

)

[inline, virtual]

Destructor.

Reimplemented in LogCabin::Client::LeaderRPC::Call.

Definition at line 169 of file LeaderRPC.h.

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Member Function Documentation

virtual void LogCabin::Client::LeaderRPCBase::Call::start	(	OpCode	opCode,
		const google::protobuf::Message &	request,
		TimePoint	timeout
	)		[pure virtual]

Invoke the RPC.

Parameters:

opCode	RPC operation code. The caller must guarantee that this is a valid opCode. (If the server rejects it, this will PANIC.)
request	The parameters for the operation. The caller must guarantee that this is a well-formed request. (If the server rejects it, this will PANIC.)
timeout	After this time has elapsed, stop trying to initiate the connection to the leader and use an invalid session, which will cause the RPC to fail later.

Implemented in LogCabin::Client::LeaderRPC::Call, LogCabin::Client::anonymous_namespace{MockClientImpl.cc}::TreeLeaderRPC::Call, and LogCabin::Client::LeaderRPCMock::Call.

virtual void LogCabin::Client::LeaderRPCBase::Call::cancel

(

)

[pure virtual]

Cancel the RPC.

This may only be called after start(), but it may be called safely from a separate thread.

Implemented in LogCabin::Client::LeaderRPC::Call, LogCabin::Client::anonymous_namespace{MockClientImpl.cc}::TreeLeaderRPC::Call, and LogCabin::Client::LeaderRPCMock::Call.

virtual Status LogCabin::Client::LeaderRPCBase::Call::wait	(	google::protobuf::Message &	response,
		TimePoint	timeout
	)		[pure virtual]

Wait for the RPC to complete.

Parameters:

[out]	response	If successful, the response to the operation will be filled in here.
	timeout	After this time has elapsed, stop waiting and return TIMEOUT. In this case, response will be left unmodified.

Returns:

True if the RPC completed successfully, false otherwise. If this returns false, it is the callers responsibility to start over to achieve the same at-most-once semantics as call().

Implemented in LogCabin::Client::LeaderRPC::Call, LogCabin::Client::anonymous_namespace{MockClientImpl.cc}::TreeLeaderRPC::Call, and LogCabin::Client::LeaderRPCMock::Call.

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Friends And Related Function Documentation

std::ostream& operator<<	(	std::ostream &	os,
		const Status &	server
	)		[friend]

Print out a Status for debugging purposes.

Definition at line 50 of file LeaderRPC.cc.

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The documentation for this class was generated from the following file:

• Client/LeaderRPC.h