Module dk.cloudcreate.essentials.components.foundation

Package dk.cloudcreate.essentials.components.foundation.messaging.eip.store_and_forward

Interface Inboxes

All Known Implementing Classes:

Inboxes.DurableQueueBasedInboxes

public interface Inboxes

The Inbox supports the transactional Store and Forward pattern from Enterprise Integration Patterns supporting At-Least-Once delivery guarantee.
The Inbox pattern is used to handle incoming messages from a message infrastructure (such as a Queue, Kafka, EventBus, etc).
The message is added to the Inbox in a transaction/UnitOfWork and afterwards the message is Acknowledged (ACK) with the message infrastructure the UnitOfWork is committed.
If the ACK fails then the message infrastructure will attempt to redeliver the message even if the UnitOfWork has been committed, since the message infrastructure and the Inbox don't share the same transactional resource. This means that messages received from the message infrastructure can be added more than once to the Inbox.
After the UnitOfWork has been committed, the messages will be asynchronously delivered to the message consumer in a new UnitOfWork.
The Inbox itself supports Message Redelivery in case the Message consumer experiences failures.
This means that the Message consumer, registered with the Inbox, can and will receive Messages more than once and therefore its message handling has to be idempotent.

If you're working with OrderedMessage's then the Inbox consumer must be configured with InboxConfig.getMessageConsumptionMode() having value MessageConsumptionMode.SingleGlobalConsumer in order to be able to guarantee that OrderedMessage's are delivered in OrderedMessage.getOrder() per OrderedMessage.getKey() across as many InboxConfig.numberOfParallelMessageConsumers as you wish to use.

Nested Class Summary

Nested Classes

Modifier and Type	Interface	Description
static class	Inboxes.DurableQueueBasedInboxes

Method Summary

Modifier and Type	Method	Description
static Inboxes	durableQueueBasedInboxes(DurableQueues durableQueues, FencedLockManager fencedLockManager)	Create an Inboxes instance that uses a DurableQueues as its storage and message delivery mechanism.
Collection<Inbox>	getInboxes()	Get all the Inbox instances managed by this Inboxes instance
Inbox	getOrCreateInbox(InboxConfig inboxConfig)	Get an existing Inbox instance or create a new instance.
default Inbox	getOrCreateInbox(InboxConfig inboxConfig, CommandBus forwardTo)	Get an existing Inbox instance or create a new instance.
Inbox	getOrCreateInbox(InboxConfig inboxConfig, Consumer<Message> messageConsumer)	Get an existing Inbox instance or create a new instance.

Method Detail

getOrCreateInbox

Inbox getOrCreateInbox(InboxConfig inboxConfig)

Get an existing Inbox instance or create a new instance. If an existing Inbox with a matching InboxName is already created then that instance is returned (irrespective of whether the redeliveryPolicy, etc. have the same values)
Remember to call Outbox.consume(Consumer) to start consuming messages

Parameters:

inboxConfig - the inbox configuration

Returns:

the Inbox

getOrCreateInbox

Inbox getOrCreateInbox(InboxConfig inboxConfig,
                       Consumer<Message> messageConsumer)

Get an existing Inbox instance or create a new instance. If an existing Inbox with a matching InboxName is already created then that instance is returned (irrespective of whether the redeliveryPolicy, etc. have the same values)

Parameters:

inboxConfig - the inbox configuration

messageConsumer - the asynchronous message consumer. See PatternMatchingMessageHandler

Returns:

the Inbox

getOrCreateInbox

default Inbox getOrCreateInbox(InboxConfig inboxConfig,
                               CommandBus forwardTo)

Get an existing Inbox instance or create a new instance. If an existing Inbox with a matching InboxName is already created then that instance is returned (irrespective of whether the redeliveryPolicy, etc. have the same values)

Parameters:

inboxConfig - the inbox configuration

forwardTo - forward messages to this command bus using CommandBus.send(Object)

Returns:

the Inbox

getInboxes

Collection<Inbox> getInboxes()

Get all the Inbox instances managed by this Inboxes instance

Returns:

all the Inbox instances managed by this Inboxes instance

durableQueueBasedInboxes

static Inboxes durableQueueBasedInboxes(DurableQueues durableQueues,
                                        FencedLockManager fencedLockManager)

Create an Inboxes instance that uses a DurableQueues as its storage and message delivery mechanism.

Parameters:

durableQueues - The DurableQueues implementation used by the Inboxes instance returned

fencedLockManager - the FencedLockManager used for Inbox's that use MessageConsumptionMode.SingleGlobalConsumer

Returns:

the Inboxes instance