reactmann

reactmann is the reactive way to monitor your apps. Built on top of rxjava and the Riemann protocol to make monitoring suck less.

Caveats

This is based on a pre-release version of vert.x and should not be considered production quality (yet).

A non-exhaustive list of TODOs':

• TCP only, for now
• No SSL support
• There's no built in way to do notifications yet. For e-mail I'll probably go with something like vertx-mail-service and there'll most likely be a Pagerduty plugin as well.
• Needs performance testing, profiling etc
• Add support for other languages, at the very least for Javascript

Usage

The simplest way to get started, assuming you're using Maven, is to use the java archetype.

mvn archetype:generate                                  \
  -DarchetypeGroupId=com.github.blakepettersson         \
  -DarchetypeArtifactId=reactmann-java-archetype        \
  -DarchetypeVersion=0.3-preview                        \
  -DgroupId={your group id}                             \
  -Dversion={your version}                              \
  -DartifactId={your artifact id}

This will generate a Maven project with a basic verticle, and a main class to run it from an IDE if desired.

In BasicVerticle.java, the generated file looks like this:

public class BasicVerticle extends RiemannVerticle {
    private final Logger log = LoggerFactory.getLogger(BasicVerticle.class);

    @Override
    public void observeStream(Observable<Event> events) {
        events.subscribe(e -> {
            log.info(e);
        });
    }
}

To try this out, cd into the project directory and compile it.

mvn package
java -jar target/{your artifact id}-{your version}-fat.jar

This will start up the Reactmann service. A simple way to see if this actually works would be to start up riemann-health. This tool requires Ruby and Rubygems to be installed first. Open up another terminal and try it out.

gem install riemann-tools

After this step, riemann-health will be available on your PATH. Running it is as simple as

riemann-health

This tool will post to localhost:5555 by default, and you should see incoming events being posted on stdout where the jar is running.