Hypertable::ConnectionHandler Class Reference

Handles incoming Master requests. More...

#include <ConnectionHandler.h>

Inheritance diagram for Hypertable::ConnectionHandler:

Collaboration diagram for Hypertable::ConnectionHandler:

Public Member Functions
	ConnectionHandler (ContextPtr &context)
	Constructor. More...
void	start_timer ()
virtual void	handle (EventPtr &event)
	Responds to Master request events. More...
Public Member Functions inherited from Hypertable::DispatchHandler
virtual	~DispatchHandler ()
	Destructor. More...

Private Member Functions
int32_t	send_id_response (EventPtr &event, OperationPtr &operation)
	Sends operation ID back to client. More...
int32_t	send_error_response (EventPtr &event, int32_t error, const String &msg)
	Sends error response message back to client. More...
int32_t	send_ok_response (EventPtr &event, bool silent=false)
	Sends OK response message back to client. More...
void	maybe_dump_op_statistics ()
	Maybe dumps OperationProcessor statistics. More...

Private Attributes
ContextPtr	m_context
	Pointer to Master context. More...

Detailed Description

Handles incoming Master requests.

An object of this class is installed as the dispatch handler for the listen socket on which the Master receives client connections and requests. To handle transparent master failover while requests are being carried out, most requests happen in two phases:

1. An operation is created to carry out the request and its ID is sent back to client
2. Client issues MasterProtocol::COMMAND_FETCH_RESULT request to fetch result of operation

After the operation has been created and persisted to the MML and the ID has been sent back to the client, the Master can fail and when the new Master comes up, it will complete the operation and send the results back to the client. This class also installs an interval timer and installs itself as the handler. When handling TIMER events, it checks to see if any of the following actions are necessary, and if so, it will create operations to carry them out.

• Statistics gathering
• Garbage collection
• Balancing

Definition at line 65 of file ConnectionHandler.h.

Constructor & Destructor Documentation

Hypertable::ConnectionHandler::ConnectionHandler ( ContextPtr &  context )

inline

Constructor.

This initializes the connection handler and installs the interval timer.

Parameters

context

Master context object

Definition at line 72 of file ConnectionHandler.h.

Member Function Documentation

void ConnectionHandler::handle ( EventPtr &  event )

virtual

Responds to Master request events.

Parameters

event

AsyncComm event corresponding to Master request

Implements Hypertable::DispatchHandler.

Definition at line 84 of file ConnectionHandler.cc.

void ConnectionHandler::maybe_dump_op_statistics ( )

private

Maybe dumps OperationProcessor statistics.

This method check for the existance of the file $HT_INSTALL_DIR/run/debug-op and if it exists, it will remove it and then call OperationProcessor::state_description() and will write the state description message to the file $HT_INSTALL_DIR/run/op.output.

Definition at line 325 of file ConnectionHandler.cc.

int32_t ConnectionHandler::send_error_response ( EventPtr &  event, int32_t  error, const String &  msg  )

private

Sends error response message back to client.

This method sends an error respons message back to the client formatted as 32-bit error code by vstring error message.

Parameters

event	AsyncComm event corresponding to Master request
error	Error code
msg	Error message

Returns

Error::OK if response send back successfully, otherwise error code returned by Comm::send_response

Definition at line 312 of file ConnectionHandler.cc.

int32_t ConnectionHandler::send_id_response ( EventPtr &  event, OperationPtr &  operation  )

private

Sends operation ID back to client.

Parameters

event	AsyncComm event corresponding to Master request
operation	Operation whose ID is to be sent back

Definition at line 286 of file ConnectionHandler.cc.

int32_t ConnectionHandler::send_ok_response ( EventPtr &  event, bool  silent = false  )

private

Sends OK response message back to client.

Parameters

event	AsyncComm event corresponding to Master request
silent	Don't log if errors encountered

Returns

Error::OK if response send back successfully, otherwise error code returned by Comm::send_response

Definition at line 300 of file ConnectionHandler.cc.

void ConnectionHandler::start_timer

(

)

Definition at line 78 of file ConnectionHandler.cc.

Member Data Documentation

ContextPtr Hypertable::ConnectionHandler::m_context

private

Pointer to Master context.

Definition at line 118 of file ConnectionHandler.h.

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

• /home/doug/src/hypertable/src/cc/Hypertable/Master/ConnectionHandler.h
• /home/doug/src/hypertable/src/cc/Hypertable/Master/ConnectionHandler.cc