This project offers a flexible implementation of an event bus design pattern in Kotlin, with an emphasis on the integration of middleware. It supports diverse communication demands between any types of components and enables additional processing layers through middleware, enhancing the modularity and adaptability of your application.

Add this to your build.gradle.kts

dependencies {
    implementation("io.github.theunic:kcommand-core")
}

import io.github.theunic.kcommand.core.SimpleMessageBus

fun main() {
    val messageBus = SimpleMessageBus<String, String>()
    messageBus.subscribe(String::class) { it.uppercase() }
    val result = messageBus.handle("hello world!")
    println(result.await()) // => "HELLO WORLD!"
}

The DefaultMessageBus makes use of corroutines, suspended functions and Kotlin's FLOW API to handle messages. It introduces the concept of Transports in order to decouple the message sending from the Message Bus allowing for other message distribution mechanisms to be able to distribute messages.

import io.github.theunic.kcommand.core.DefaultMessageBus
import kotlinx.coroutines.runBlocking

fun main() {
    val messageBus = DefaultMessageBus<String, Int>()
    messageBus.subscribe(String::class) { it.length }
    runBlocking {
        val result = messageBus.handle("hello world!")
        println(result.await()) // => 12
    }
}

Contributions of all sizes are welcome.

To contribute:

1. Fork the project.
2. Create your feature branch: git checkout -b my-new-feature.
3. Commit your changes: git commit -am 'Add some feature'.
4. Push to the branch: git push origin my-new-feature.
5. Submit a pull request.

Before your PR can be approved, please ensure that it does not fail any CI checks.

This project is licensed under a standard MIT license. Check the LICENSE.md file for more details.