The New Helidon CLI

One of the new features in Helidon 2.0 is the addition of a Command Line Interface or CLI. The Helidon CLI enables developers to get started with Helidon with minimal effort: you can create a new application, build it, run it, and more, by writing some simple commands.

In particular, you can use the so-called development loop, or devloop for short. It builds and runs the application, monitors its source files, and restarts the application on every update, thus enabling developers to learn about Helidon in a fully interactive manner.

The CLI is distributed as a standalone executable (compiled using GraalVM) for ease of installation. It is currently available as download for Linux and Mac. Simply download the binary, install it at a location accessible from your PATH and you’re ready to go!

Let’s Take a Closer Look

Instead of going through a long description on how the CLI works, let’s show the CLI’s capabilities using screencasts!

In this first video will shall see how to generate, build and test a project created from one of the Helidon archetypes:

With the project generated, we can start the devloop and test changes to our application. Let’s see how that works in the following screencast.

During the execution of the devloop, any change to an application’s source file such as a Java file, a resource file or a pom file, will automatically cause the application to restart and the changes to be immediately visible to the developer. It is as easy as it sounds!

What’s Next?

The main goal of the CLI is for anyone starting with Helidon to be able to create an application by choosing one of the archetypes and get it running within seconds and without the need for any large downloads — the CLI binary is only a few megabytes long.

The current version only supports Maven, but support for Gradle is in our roadmap. Stay tuned!