vert.x-utils

A collection of utilities for Vert.x which allow for simplified deployment, standardized logging, rescheduling of handlers, and a file based health check handler.

Usage

RescheduleHandler

Provides the ability to execute a handler on a timer and reschedule on completion.

RescheduleHandler rescheduleHandler = new RescheduleHandler(vertx, event -> { }, 1000);
vertx.setTimer(1000, rescheduleHandler);

MainVerticle

Used to deploy a configurable number of instances of different verticles and enforce dependencies between the verticles. The number of instances may be specified as a multiple per core by suffixing the value with "C" (e.g. "instances":"2C" is two instances per core).

The configuration also allows you to optionally register one or more MessageCodec implementations by specifying an array of fully qualified class names. Each MessageCodec class is required to have a no-args public constructor.

Example mainConf.json:

{
  "verticles": {
    "MetricsVerticle": {
      "class": "com.groupon.vertx.utils.MetricsVerticle",
      "instances": 1,
      "worker": true,
      "config": { }
    },
    "ExampleVerticle": {
      "class": "com.groupon.example.verticle.ExampleVerticle",
      "instances": 1,
      "worker": true,
      "config": { },
      "dependencies": [ "MetricsVerticle" ]
    }
  },
  "messageCodecs": [
    "com.groupon.example.vertx.MyMessageCodec"
  ]
}

Example mod.json:

{
  "main": "com.groupon.vertx.utils.MainVerticle",
  "preserve-cwd": true,
  "worker": false
}

Starting Vert.x with MainVerticle

java -cp conf:lib/* org.vertx.java.platform.impl.cli.Starter runmod com.groupon.example~release -instances 1 -conf conf/mainConf.json

Logger

A wrapper to provide standardized logging calls using slf4j and the com.arpnetworking.logback.StenoMarker

Logger log = Logger.getLogger(Example.class);
log.info("sampleMethod", "Hello logging world!");

Configuration

In the MainVerticle's configuration each child verticle's config key is either an inline JSON object or a String representing a file path. If you specify a file path you may also specify a custom parser with the system property vertx-utils.config-parser-class-name (e.g. -Dvertx-utils.config-parser-class-name=com.example.MyParser). This parser receives the file contents and is required to return a Vert.x JsonObject. Use it to translate your preferred configuration (e.g. hocon, properties, yaml, xml, etc.) into JSON.