This class is used to send RPCs from clients to the leader of the LogCabin cluster. More...

#include <LeaderRPC.h>

Inheritance diagram for LogCabin::Client::LeaderRPCBase:

Classes
class	Call
	An asynchronous version of call(). More...
Public Types
enum	Status { OK, TIMEOUT, INVALID_REQUEST }
	Return type for LeaderRPCBase::call(). More...
typedef RPC::ClientRPC::Clock	Clock
	Clock used for timeouts.
typedef RPC::ClientRPC::TimePoint	TimePoint
	Type for absolute time values used for timeouts.
typedef Protocol::Client::OpCode	OpCode
	RPC operation code.
Public Member Functions
	LeaderRPCBase ()
	Constructor.
virtual	~LeaderRPCBase ()
	Destructor.
virtual Status	call (OpCode opCode, const google::protobuf::Message &request, google::protobuf::Message &response, TimePoint timeout)=0
	Execute an RPC on the cluster leader.
virtual std::unique_ptr< Call >	makeCall ()=0
	Return a new Call object.
	LeaderRPCBase (const LeaderRPCBase &)
LeaderRPCBase &	operator= (const LeaderRPCBase &)
Friends
std::ostream &	operator<< (std::ostream &os, const Status &server)
	Print out a Status for debugging purposes.

Detailed Description

This class is used to send RPCs from clients to the leader of the LogCabin cluster.

It automatically finds and connects to the leader and transparently rolls over to a new leader when necessary.

There are two implementations of this interface: LeaderRPC is probably the one you're interested in. LeaderRPCMock is used for unit testing only.

Definition at line 61 of file LeaderRPC.h.

Member Typedef Documentation

Clock used for timeouts.

Definition at line 64 of file LeaderRPC.h.

Type for absolute time values used for timeouts.

Definition at line 66 of file LeaderRPC.h.

RPC operation code.

Definition at line 71 of file LeaderRPC.h.

Enumerator:

OK	The RPC completed scucessfully.
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 76 of file LeaderRPC.h.

LogCabin::Client::LeaderRPCBase::LeaderRPCBase ( ) [inline]

Constructor.

Definition at line 98 of file LeaderRPC.h.

virtual LogCabin::Client::LeaderRPCBase::~LeaderRPCBase ( ) [inline, virtual]

Destructor.

Definition at line 101 of file LeaderRPC.h.

LogCabin::Client::LeaderRPCBase::LeaderRPCBase ( const LeaderRPCBase & )

virtual Status LogCabin::Client::LeaderRPCBase::call	(	OpCode	opCode,
		const google::protobuf::Message &	request,
		google::protobuf::Message &	response,
		TimePoint	timeout
	)		`[pure virtual]`

Execute an RPC on the cluster leader.

This class guarantees that the RPC will be executed at least once.

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 waiting and return TIMEOUT. In this case, response will be left unmodified.
[out]	response	The response to the operation will be filled in here.