Dynamic registration of Spring Integration adapters using functional bean definition with the Spring Framework 5.0 Kotlin DSL.

DynamicIntegration.kt

package com.example.feed

import com.rometools.rome.feed.synd.SyndEntry
import org.springframework.boot.autoconfigure.SpringBootApplication
import org.springframework.boot.builder.SpringApplicationBuilder
import org.springframework.context.support.beans
import org.springframework.core.io.UrlResource
import org.springframework.integration.dsl.IntegrationFlows
import org.springframework.integration.feed.dsl.Feed
import org.springframework.integration.handler.GenericHandler


// add org.springframework.boot:spring-boot-starter-integration and
// org.springframework.integration:spring-integration-feed to your CLASSPATH
// for this to work.

@SpringBootApplication
class FeedApplication

fun main(args: Array<String>) {

  fun processSyndEntry(syndEntry: SyndEntry) {
    // todo
  }

  SpringApplicationBuilder()
  .initializers(
  	beans {
  		val feeds = mapOf("atom" to listOf("https://spring.io/blog.atom"),
  				"rss" to listOf("https://cloudfoundry.org/feed/"))
  		feeds.entries.forEach { e ->
  			e.value.forEach { url ->
  				val urlAsKey = url.filter { !it.isLetterOrDigit() }
  				bean(name = "feedFlorFor${urlAsKey}") {
  					IntegrationFlows
  							.from(Feed.inboundAdapter(UrlResource(url), urlAsKey), { it.poller({ it.fixedDelay(1000) }) })
  							.handle(GenericHandler<SyndEntry> { syndEntry, headers ->
  								processSyndEntry(syndEntry)
  							})
  							.get()
  				}
  			}
  		}
  	}
    )
    .sources(FeedApplication::class.java)
    .run(*args)
}

There's a lot going on here. This uses Spring Boot 2.x which in turn uses Spring Framework 5.0 which in turn supports functional (programmatic) bean definition. There's also a nice Kotlin DSL in Spring Framework 5.0, so this example uses the Kotlin language. Finally, this example dynamically registers Spring Integration inbound adapters with functional bean definitions.

I've done an Small PR that will make even more beautiful that code! Just a couple of Kotlin extensions functions!

spring-projects/spring-boot#11527

It's my first PR ! so excited!!