Abstract base class for server protocol drivers. More...

#include <Protocol.h>

Inheritance diagram for Hypertable::Protocol:

Public Member Functions
virtual	~Protocol ()
	Destructor. More...

virtual const char *	command_text (uint64_t command)=0
	Returns the string representation of a command code. More...

Static Public Member Functions
static int32_t	response_code (const Event *event)
	Returns the response code from an event `event` generated in response to a request message. More...

static int32_t	response_code (const EventPtr &event)
	Returns the response code from an event `event` generated in response to a request message. More...

static String	string_format_message (const Event *event)
	Returns error message decoded standard error MESSAGE generated in response to a request message. More...

static String	string_format_message (const EventPtr &event)
	Returns error message decoded from standard error MESSAGE generated in response to a request message. More...

static CommBufPtr	create_error_message (CommHeader &header, int error, const char *msg)
	Creates a standard error message response. More...

Detailed Description

Abstract base class for server protocol drivers.

This is the base class for all server protocol drivers. A server protocol driver is responsible for encoding and decoding messages sent and received to and from a service.

Definition at line 49 of file Protocol.h.

Constructor & Destructor Documentation

virtual Hypertable::Protocol::~Protocol ( )

inlinevirtual

Destructor.

Definition at line 54 of file Protocol.h.

Member Function Documentation

virtual const char* Hypertable::Protocol::command_text ( uint64_t command )

pure virtual

Returns the string representation of a command code.

Each protocol defines a set of command codes that are sent in the CommHeader::command field of a reqeust's message header to indicate which server command (method) is to be executed. This method returns a human readable string mnemonic for the command.

Parameters

command Command code

Returns: Pointer to human readable string mnemonic for command.

Implemented in Hyperspace::Protocol.

CommBufPtr Protocol::create_error_message	(	CommHeader &	header,
		int	error,
		const char *	msg
	)

static

Creates a standard error message response.

This method creates a standard error message response encoded in the following format:

  [int32] error code
  [int16] error message length
  [chars] error message

Parameters

header	Reference to header to use in response buffer
error	Error code
msg	Error message

Returns: Pointer to Commbuf message holding standard error response

Definition at line 81 of file Protocol.cc.

int32_t Protocol::response_code ( const Event * event )

static

Returns the response code from an event event generated in response to a request message.

If event is of type ERROR, then event->error is returned, otherwise the response code is decoded from the first four bytes of the message payload.

Returns: Error or response code from event or Error::SERIALIZATION_INPUT_OVERRUN if payload of MESSAGE event is less than 4 bytes.

Definition at line 39 of file Protocol.cc.

static int32_t Hypertable::Protocol::response_code ( const EventPtr & event )

inlinestatic

Returns the response code from an event event generated in response to a request message.

If event is of type ERROR, then event->error is returned, otherwise the response code is decoded from the first four bytes of the message payload.

Returns: Error or response code from event or Error::SERIALIZATION_INPUT_OVERRUN if payload of MESSAGE event is less than 4 bytes.

Definition at line 76 of file Protocol.h.

String Protocol::string_format_message ( const Event * event )

static

Returns error message decoded standard error MESSAGE generated in response to a request message.

When a request to a service method results in an error, the error code an message are typically returned in a response message encoded in the following format:

  [int32] error code
  [int16] error message length
  [chars] error message

This method extracts and returns the error message from a response MESSAGE event.

Note: The semantics of this method are wacky, it should be re-written

Parameters

event Pointer to MESSAGE event received in response to a request

Returns: Error message

Definition at line 51 of file Protocol.cc.

static String Hypertable::Protocol::string_format_message ( const EventPtr & event )

inlinestatic

Returns error message decoded from standard error MESSAGE generated in response to a request message.

When a request to a service method results in an error, the error code an message are typically returned in a response message encoded in the following format:

  [int32] error code
  [int16] error message length
  [chars] error message

This method extracts and returns the error message from a response MESSAGE event.

Note: The semantics of this method are wacky, it should be re-written

Parameters

event Pointer to MESSAGE event received in response to a request

Returns: Error message

Definition at line 112 of file Protocol.h.

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

/home/doug/src/hypertable/src/cc/AsyncComm/Protocol.h
/home/doug/src/hypertable/src/cc/AsyncComm/Protocol.cc

Public Member Functions

Static Public Member Functions

Detailed Description

Constructor & Destructor Documentation

Member Function Documentation