Scala DSL - EIP

Messaging systems

Pipeline

There is a simple syntax available for specifying pipeline, by simple putting to or → between the different steps in the pipeline.

For more advanced use cases, you can also use a block-based syntax, where every step in the pipeline starts with either to or →.

Filter

For a message filter, use the when() method with a parameter of type The Exchange ⇒ Boolean. In the example below, we use a Scala convenience method named in to access the 'in' message body; only messages where the 'in' message is <hello/> will arrive at the mock:a endpoint.

Once again, if you need to specify a more advanced route, you can use the more elaborate syntax.

Message routing

Content based router

Similar to the Filter , the content based router uses when methods with Exchange ⇒ Boolean function literals and an optional otherwise. The function literal can contain plain Scala code as well as any of the supported languages . The example below routes a given message based on the language of the message body.

Splitter

To handle large message in smaller chunks, you can write a Scala Exchange ⇒ Any* method and add it to your route with the splitter method. As with many other EIPs, we support a short, in-line version as well as a more elaborate block based one.

The above examples also show you how other languages like XPath can be within the Scala DSL.

TODO

TODO: Create a Scala alternative and example for every EIP available on http://activemq.apache.org/camel/enterprise-integration-patterns.html

• Message Channel
• Message
• Message Router
• Message Translator
• Message Endpoint
• Point to Point Channel
• Publish Subscribe Channel
• Dead Letter Channel
• Guaranteed Delivery
• Message Bus
• Correlation Identifier
• Recipient List
• Aggregator
• Resequencer
• Routing Slip
• Throttler
• Delayer
• Load Balancer
• Multicast
• Content Enricher
• Content Filter
• Normalizer
• Messaging Mapper
• Event Driven Consumer
• Polling Consumer
• Competing Consumers
• Message Dispatcher
• Selective Consumer
• Durable Subscriber
• Idempotent Consumer
• Transactional Client
• Messaging Gateway
• Service Activator
• Wire Tap