Changes between 5.2 and 5.3

New Components

Integration Pattern

The IntegrationPattern abstraction has been introduced to indicate which enterprise integration pattern (an IntegrationPatternType) and category a Spring Integration component belongs to. See its JavaDocs and Integration Graph for more information about this abstraction and its use-cases.

`ReactiveMessageHandler`

The ReactiveMessageHandler is now natively supported in the framework. See ReactiveMessageHandler for more information.

`ReactiveMessageSourceProducer`

The ReactiveMessageSourceProducer is a reactive implementation of the MessageProducerSupport to wrap a provided MessageSource into a Flux for on demand receive() calls. See Reactive Streams Support for more information.

Java DSL Extensions

A new IntegrationFlowExtension API has been introduced to allow extension of the existing Java DSL with custom or composed EIP-operators. This also can be used to introduce customizers for any out-of-the-box IntegrationComponentSpec extensions. See DSL Extensions for more information.

Kotlin DSL

The Kotlin DSL for integration flow configurations has been introduced. See Kotlin DSL Chapter for more information.

ReactiveRequestHandlerAdvice

A ReactiveRequestHandlerAdvice is provided to customize Mono replies from message handlers. See Reactive Advice for more information.

HandleMessageAdviceAdapter

A HandleMessageAdviceAdapter is provided to wrap any MethodInterceptor for applying on the MessageHandler.handleMessage() instead of a default AbstractReplyProducingMessageHandler.RequestHandler.handleRequestMessage() behavior. See Handling Message Advice for more information.

MongoDB Reactive Channel Adapters

The spring-integration-mongodb module now provides channel adapter implementations for the Reactive MongoDb driver support in Spring Data. Also, a reactive implementation for MongoDb change stream support is present with the MongoDbChangeStreamMessageProducer. See MongoDB Support for more information.

ReceiveMessageAdvice

A special ReceiveMessageAdvice has been introduced to proxy exactly MessageSource.receive() or PollableChannel.receive(). See Smart Polling for more information.

General Changes

The gateway proxy now doesn’t proxy default methods by default. See Invoking default Methods for more information.

Internal components (such as _org.springframework.integration.errorLogger) now have a shortened name when they are represented in the integration graph. See Integration Graph for more information.

In the aggregator, when the MessageGroupProcessor returns a Message, the MessageBuilder.popSequenceDetails() is performed on the output message if the sequenceDetails matches the header in the first message of the group. See Aggregator Programming Model for more information.

A new publishSubscribeChannel() operator, based on the BroadcastCapableChannel and BroadcastPublishSubscribeSpec, was added into Java DSL. This fluent API has its advantage when we configure sub-flows as pub-sub subscribers for broker-backed channels like SubscribableJmsChannel, SubscribableRedisChannel etc. See Sub-flows support for more information.

Transactional support in Spring Integration now also includes options to configure a ReactiveTransactionManager if a MessageSource or MessageHandler implementation produces a reactive type for payload to send. See TransactionInterceptorBuilder for more information. See also Reactive Transactions.

A new intercept() operator to register ChannelInterceptor instances without creating explicit channels was added into Java DSL. See Operator intercept() for more information.

The MessageStoreSelector has a new mechanism to compare an old and new value. See Idempotent Receiver Enterprise Integration Pattern for more information.

The MessageProducerSupport base class now has a subscribeToPublisher(Publisher<? extends Message<?>>) API to allow implementation of message-driven producer endpoints which emit messages via reactive Publisher. See Reactive Streams Support for more information.

AMQP Changes

The outbound channel adapter has a new property multiSend allowing multiple messages to be sent within the scope of one RabbitTemplate invocation. See AMQP Outbound Channel Adapter for more information.

The inbound channel adapter now supports a listener container with the consumerBatchEnabled property set to true. See AMQP Inbound Channel Adapter

HTTP Changes

The encodeUri property on the AbstractHttpRequestExecutingMessageHandler has been deprecated in favor of newly introduced encodingMode. See DefaultUriBuilderFactory.EncodingMode JavaDocs and Controlling URI Encoding for more information. This also affects WebFluxRequestExecutingMessageHandler, respective Java DSL and XML configuration. The same option is added into an AbstractWebServiceOutboundGateway.

Web Services Changes

Java DSL support has been added for Web Service components. The encodeUri property on the AbstractWebServiceOutboundGateway has been deprecated in favor of newly introduced encodingMode - similar to HTTP changes above. See Web Services Support for more information.

TCP Changes

The FailoverClientConnectionFactory no longer fails back, by default, until the current connection fails. See TCP Failover Client Connection Factory for more information.

The TcpOutboundGateway now supports asynchronous request/reply. See TCP Gateways for more information.

You can now configure client connections to perform some arbitrary test on new connections. See Testing Connections for more information.

RSocket Changes

A decodeFluxAsUnit option has been added to the RSocketInboundGateway with the meaning to decode incoming Flux as a single unit or apply decoding for each event in it. See RSocket Inbound Gateway for more information.

Zookeeper Changes

A LeaderInitiatorFactoryBean (as well as its XML <int-zk:leader-listener>) exposes a candidate option for more control over a Candidate configuration. See Leadership event handling for more information.

MQTT Changes

The inbound channel adapter can now be configured to provide user control over when a message is acknowledged as being delivered. See Manual Acks for more information.

The outbound adapter now publishes a MqttConnectionFailedEvent when a connection can’t be created, or is lost. Previously, only the inbound adapter did so. See MQTT Events.

(S)FTP Changes

The FileTransferringMessageHandler (for FTP and SFTP, for example) in addition to File, byte[], String and InputStream now also supports an org.springframework.core.io.Resource. See SFTP Support and FTP Support for more information.

File Changes

The FileSplitter doesn’t require a Jackson processor (or similar) dependency any more for the markersJson mode. It uses a SimpleJsonSerializer for a straightforward string representation of the FileSplitter.FileMarker instances. See FileSplitter for more information.