martinscmb / smallrye-reactive-messaging

MicroProfile Reactive Messaging Implementation

Implementation of the MicroProfile Reactive Messaging specification

This project is an implementation of the (next to be) Eclipse MicroProfile Reactive Messaging specification - a CDI extension to build data streaming application. It provides support for:

• Apache Kafka
• MQTT
• AMQP 1.0
• Apache Camel

It also provides a way to inject streams into CDI beans, and so link your Reactive Messaging streams into CDI beans, or JAX-RS resources.

Getting started

Prerequisites

The build process requires Apache Maven and Java 8+ and can be performed using:

mvn clean install

How to start

The best way to start is to look at the examples/quickstart project. It's a Maven project listing the minimal set of dependencies and containing a single class:

package io.smallrye.reactive.messaging.quickstart;

import org.eclipse.microprofile.reactive.messaging.Incoming;
import org.eclipse.microprofile.reactive.messaging.Outgoing;
import org.eclipse.microprofile.reactive.streams.operators.PublisherBuilder;
import org.eclipse.microprofile.reactive.streams.operators.ReactiveStreams;

import javax.enterprise.context.ApplicationScoped;
import javax.enterprise.inject.se.SeContainerInitializer;

@ApplicationScoped
public class QuickStart {

  public static void main(String[] args) {
    SeContainerInitializer.newInstance().initialize();
  }


  @Outgoing("source")
  public PublisherBuilder<String> source() {
    return ReactiveStreams.of("hello", "with", "SmallRye", "reactive", "message");
  }

  @Incoming("source")
  @Outgoing("processed-a")
  public String toUpperCase(String payload) {
    return payload.toUpperCase();
  }

  @Incoming("processed-a")
  @Outgoing("processed-b")
  public PublisherBuilder<String> filter(PublisherBuilder<String> input) {
    return input.filter(item -> item.length() > 4);
  }

  @Incoming("processed-b")
  public void sink(String word) {
    System.out.println(">> " + word);
  }

}

Run the project with: mvn compile exec:java -Dexec.mainClass=io.smallrye.reactive.messaging.quickstart.QuickStart:

>> HELLO
>> SMALLRYE
>> REACTIVE
>> MESSAGE

Built With

• Apache Vert.x
• RX Java 2
• SmallRye Reactive Stream Operators (any implementation would work)
• Weld (any implementation would work)

Contributing

Please read CONTRIBUTING.md for details, and the process for submitting pull requests.

Sponsors

The project is sponsored by Red Hat.

License

This project is licensed under the Apache License 2.0 - see the LICENSE file for details.