FRI-DAY / elasticmq-gradle-plugin

Sample Gradle plugin wrapping ElasticMQ - Custom DSL for configuring each instance

ElasticMQ Gradle Plugin

This plugin allows you to easily integrate ElasticMQ in your Gradle builds! With it you can easily start and stop queue instances with different configurations at any point of your build.

Usage

To apply the plugin you just need to add it to the plugin list!

plugins {
    id 'de.friday.elasticmq' version '1.0.0-SNAPSHOT'
}

NOTE: Currently the plugin is not yet published to the Gradle Plugin Portal, however you can still apply it as above (to make it as compatible as possible with when it does get published) by building the Shadow Jar and managing your plugins in the settings, as can be seen in the Integration Tests.

After applying the plugin you have access to a custom DSL that allows you to easily configure several ElasticMQ instances. An example with the Groovy DSL:

elasticmq {
    instances {
        local {
            protocol = 'http'
            host = 'localhost'
            port = 9324
            contextPath = 'path'

            limits = 'relaxed'

            queues {
                sample {
                    attribute 'DelaySeconds', '0'
                }
            }
        }
    }
}

In the above example you can see that a single ElasticMQ instance was configured, named local, and that it is using the http protocol on the localhost, exposing itself in port 9324. Furthermore, this instance is configured to use the relaxed option for the SQS Limits instead of the default strict mode. It also overrides the default blank Context Path to be path. The meaning of these configuration options can be consulted on the official ElasticMQ repository since they are exposed one to one. The instance is also pre-configured with a queue named sample that just specifies one attribute, DelaySeconds, to be 0. Note that instead of adding attributes one on one with the attribute method you can also just override the attributes variable directly.

The above configuration will automatically generate two tasks: startLocalElasticMq and stopLocalElasticMq, which start and stop the configured ElasticMQ instance respectively. Note that these tasks are not automatically wired to any other task, giving you the complete control on how to manage the instances.

Motivation

This plugin is mainly an exercise of learning how to develop Gradle plugins, from architecture design to complete testing, while trying to use best practices as much as possible. By focusing the center piece of the plugin in management of server instances we have a use case to learn how to develop a configurationn DSL as well as tests that integrate and validate that said instances were actually started, configured and stopped as told.

Since the main focus of the project is to learn we welcome experimenting with new ways of achieving results. We also aim at achieving a base architecture that can be applied to new plugins, so improvements over the existing architecture, implementation of best practices or tests are also highly welcome.