BloombergLP::rmqa::TracingMessageGuard Class Reference

Controls acknowledgements passed to broker for consumed messages. More...

#include <rmqa_tracingmessageguard.h>

Inheritance diagram for BloombergLP::rmqa::TracingMessageGuard:

Collaboration diagram for BloombergLP::rmqa::TracingMessageGuard:

Classes
class	Factory

Public Types
typedef bsl::function< void(const rmqt::ConsumerAck &)>	MessageGuardCallback

Public Member Functions
rmqp::TransferrableMessageGuard	transferOwnership () BSLS_KEYWORD_OVERRIDE
	TracingMessageGuard (const rmqt::Message &message, const rmqt::Envelope &envelope, const MessageGuardCallback &ackCallback, rmqp::Consumer *consumer, const bsl::string &queueName, const bsl::shared_ptr< const rmqt::Endpoint > &endpoint, const bsl::shared_ptr< rmqp::ConsumerTracing > &contextFactory)
	TracingMessageGuard (const TracingMessageGuard &obj)
const rmqt::Message &	message () const BSLS_KEYWORD_OVERRIDE
	Access the received message. More...
const rmqt::Envelope &	envelope () const BSLS_KEYWORD_OVERRIDE
	Access the received message envelope (delivery details) More...
void	ack () BSLS_KEYWORD_OVERRIDE
void	nack (bool requeue=true) BSLS_KEYWORD_OVERRIDE
virtual rmqp::Consumer *	consumer () const BSLS_KEYWORD_OVERRIDE
	Pointer to the Consumer, e.g. to cancel the message flow. More...

Protected Types
enum	State { READY , TRANSFERRED , RESOLVED }

Protected Member Functions
State	state () const

Detailed Description

Controls acknowledgements passed to broker for consumed messages.

A TracingMessageGuard is passed to the rmqa::Consumer callback function (defined in rmqp::Consumer) for each message in the event that ConsumerTracing is enabled. The difference being that the ConsumerTracing context is created from the thread that will process the message callback, and the context will be bound to the messageGuard. The object allows acknowledging either positively or negatively, with options to requeue. If a MessageGuard object is allowed to destruct before ack/nack is called a nack with requeue is automatically signaled to the broker.

Member Enumeration Documentation

State

enum BloombergLP::rmqa::MessageGuard::State

protectedinherited

Ready - not resolved yet Invalid - ownership moved Resolved - message (n)acked.

Constructor & Destructor Documentation

TracingMessageGuard() [1/2]

BloombergLP::rmqa::TracingMessageGuard::TracingMessageGuard	(	const rmqt::Message &	message,
		const rmqt::Envelope &	envelope,
		const MessageGuardCallback &	ackCallback,
		rmqp::Consumer *	consumer,
		const bsl::string &	queueName,
		const bsl::shared_ptr< const rmqt::Endpoint > &	endpoint,
		const bsl::shared_ptr< rmqp::ConsumerTracing > &	contextFactory
	)

Constructs a new valid guard

Parameters

message	Consumed message
envelope	Consumed delivery metadata
ackCallback	Callback called when resolving message
consumer	Pointer to the Consumer

TracingMessageGuard() [2/2]

BloombergLP::rmqa::TracingMessageGuard::TracingMessageGuard

(

const TracingMessageGuard &

obj

)

During copying obj is invalidated and thereafter cannot be used to (n)ack.

Member Function Documentation

ack()

void BloombergLP::rmqa::MessageGuard::ack ( )

virtualinherited

Acknowledge the received message. Callable only once. Should only be called after the message has been fully processed

A message acknowledgement is fire-and-forget. If the broker does not receive this (e.g. due to connection drop), the message will be redelivered to another consumer.

Implements BloombergLP::rmqp::MessageGuard.

consumer()

rmqp::Consumer * BloombergLP::rmqa::MessageGuard::consumer ( ) const

virtualinherited

Pointer to the Consumer, e.g. to cancel the message flow.

Implements BloombergLP::rmqp::MessageGuard.

envelope()

const rmqt::Envelope & BloombergLP::rmqa::MessageGuard::envelope ( ) const

virtualinherited

Access the received message envelope (delivery details)

Implements BloombergLP::rmqp::MessageGuard.

message()

const rmqt::Message & BloombergLP::rmqa::MessageGuard::message ( ) const

virtualinherited

Access the received message.

Implements BloombergLP::rmqp::MessageGuard.

nack()

void BloombergLP::rmqa::MessageGuard::nack ( bool  requeue = true )

virtualinherited

Negative acknowledge the received message. Callable only once.

Parameters

requeue

true requeues the message on the broker for redelivery , if false, then the message will be either dead lettered (if a dead letter exchange is specified) or dropped if not.

Implements BloombergLP::rmqp::MessageGuard.

transferOwnership()

rmqp::TransferrableMessageGuard BloombergLP::rmqa::TracingMessageGuard::transferOwnership ( )

virtual

Transfers ownership of the message processing to a MessageGuard that is copyable (shared pointer semantics) RETURN a shared pointer to a valid message guard,

Note

if the MessageGuard has already been resolved or transferred (ack/nack) a warning will be printed

Reimplemented from BloombergLP::rmqa::MessageGuard.

---

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

• src/rmq/rmqa/rmqa_tracingmessageguard.h
• src/rmq/rmqa/rmqa_tracingmessageguard.cpp