Hello world

Your first Fluxzero handler

Let’s make sure everything’s working.

In this mini-tutorial we’re going to create the simplest possible Fluxzero app — just a single HTTP endpoint.

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1. Create a project

If you haven’t created a project yet, follow the installation guide first.

Open the generated Basic Starter project in your editor. Its Spring setup discovers handler classes in the application’s root package.

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2. Add an endpoint

Create a file named HelloEndpoint.java (or .kt) in the root package:

Java

@Component
public class HelloEndpoint {

    @HandleGet("/hello")
    public String hello() {
        return "Hello from Fluxzero!";
    }
}

Kotlin

@Component
class HelloEndpoint {

    @HandleGet("/hello")
    fun hello(): String {
        return "Hello from Fluxzero!"
    }
}

@HandleGet("/hello") connects the path to the method. The returned string becomes the HTTP response body. @Component lets the starter’s Spring setup register this handler. Outside Spring, register a handler instance explicitly.

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3. Run your app

From the project directory, start the local development environment:

fz dev

Open the application URL shown by the CLI and append /hello. The local development guide explains the Devboard and preview.

You should see:

Hello from Fluxzero!

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4. What’s next?

You’ve just added your first Fluxzero handler!

Continue with Core concepts to add stored state and commands, or build the to-do app step by step.