Let's Build a Storyteller with Spring AI

Photo Courtesy DevDocsMaster

Remember those childhood summer holidays? After a long day of cricket in the neighbourhood lane, we’d all gather around, and there was always someone—a grandparent, an uncle, or an older cousin—who was the master storyteller.

I still remember my Mom, she could spin up the most fascinating tales out of thin air. Stories of a clever fox who outsmarted a lion, a tiny sparrow on a big adventure, or a king who learned a lesson from a poor farmer. We’d listen, completely captivated, our imaginations painting vivid pictures. Those simple stories were a magical part of growing up.

Now, as developers, what if we could bring a slice of that magic into our digital world? How about we build our very own storyteller? An application where you give it a tiny spark of an idea—say, "a curious robot who discovers desi chai"—and it instantly writes a wonderful short story for you.

Sounds like a fun project, right? But my mind immediately jumps to the challenges. Figuring out complex AI libraries, handling API calls, all that backend hassle… it seems like it would take all the fun out of it. How can we build something so creative using our solid, reliable Java and Spring Boot?

Well, this is where the story gets really interesting for us. It turns out, the brilliant minds at Spring have already thought about this. And their answer is Spring AI.

So, What’s All This Hungama About Spring AI?

Think of Spring AI as a friendly bridge. On one side, you have your solid, dependable Spring Boot application. On the other, you have the incredible power of AI models like OpenAI's GPT, Google's Gemini, and others. Spring AI connects these two worlds so seamlessly that you'll wonder why you ever thought AI was difficult.

In simple terms, it takes away all the boilerplate code and complex configurations. You don't have to manually handle HTTP requests to AI services or parse messy JSON responses. Spring AI gives you a clean, straightforward way to talk to AI, just like you would talk to any other service in your Spring application.

Let's Build Something! Your First AI-Powered Spring Boot App

Enough talk, let’s get our hands dirty. Let's build our little "Story Generator." You need to give a simple idea, and it cooks up a short story for you.

We'll be building this faster than it takes to get your food delivery on a Friday night.

Step 1: The Foundation - Setting Up Your Project

First things first, we need a basic Spring Boot project. The easiest way is to use the Spring Initializr. It’s our go-to starting point for any new Spring project.

1. Head over to start.spring.io.
2. Choose Maven as the project type and Java as the language.
3. Select a recent stable version of Spring Boot (3.2.x or higher is good).
4. Give your project a name, something like ai-story-generator.
5. Now, for the important part – the dependencies. Add the following:
   • Spring Web: Because we want to create a REST endpoint.
   • Spring Boot Actuator: Good practice to monitor our app.
   • OpenAI: This is the Spring AI magic wand we need. Just type "OpenAI" and add the dependency.

Once you’re done, click "Generate". A zip file will be downloaded. Unzip it and open the project in your favourite IDE (IntelliJ or VS Code, your choice!).

Step 2: The Secret Ingredient - Your API Key

To talk to an AI model like OpenAI's, you need an API key. It's like a secret password.

1. Go to the OpenAI Platform and create an account.
2. Navigate to the API Keys section and create a new secret key.
3. Important: Copy this key immediately and save it somewhere safe. You won’t be able to see it again!

Now, open the src/main/resources/application.properties file in your project and add this line:

spring.ai.openai.api-key=YOUR_OPENAI_API_KEY_HERE

Step 3: Writing the Code - Where the Magic Happens

This is the best part. You'll be surprised at how little code we need to write.

Let's create a simple REST controller. Create a new Java class called StoryController.java.

package com.bhargav.ai.storygenerator;

import org.springframework.ai.chat.client.ChatClient;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RequestParam;
import org.springframework.web.bind.annotation.RestController;

@RestController

public class StoryController {

    private final ChatClient chatClient;

    public StoryController(ChatClient.Builder chatClientBuilder) {

        this.chatClient = chatClientBuilder.build();

    }

    @GetMapping("/story")

    public String generateStory(@RequestParam(value = "topic",
            defaultValue = "a curious robot who discovered desi chai") String topic) {

        return this.chatClient.prompt()

                .user("Tell me a short story about " + topic)

                .call()

                .content();

    }

}

Let's break down this simple code, shall we?

• @RestController: This tells Spring that this class will handle web requests.

• private final ChatClient chatClient;: This is the hero of our story! The ChatClient is a part of Spring AI that makes talking to the AI model incredibly easy. We inject it using the constructor. Spring Boot automatically configures it for us because we added the OpenAI dependency and the API key. No manual setup needed. Kitna aasan hai! (How easy is that!)

• @GetMapping("/story"): This creates a web endpoint. You can access it at http://localhost:8080/story.

• The generateStory method is where the action is.

• chatClient.prompt(): We start building our request to the AI.

• .user("Tell me a short story about " + topic): We are telling the AI what to do. This is our "prompt." We take a topic from the user's request.

• .call(): This sends our request to the AI model.

• .content(): This gets the text response back from the AI.

And that’s it! We’re done. Seriously.

Step 4: Run the Application!

Now, just run your Spring Boot application from your IDE. Once it starts up, open your web browser and go to:

http://localhost:8080/story

You should see a short story about a curious robot discovering chai.

Want to try another topic? Just add a topic parameter to the URL:

http://localhost:8080/story?topic=a cat who wanted to be a software engineer in Bengaluru

And watch as the AI instantly generates a new story for you.

What Did We Just Do?

Think about it. In just a few minutes, with a handful of dependencies and less than 20 lines of Java code, we built an AI-powered application. We didn't have to wrestle with HTTP clients, authentication headers, or complex JSON.

We just told Spring AI what we wanted, and it did the needful.

This is just the tip of the iceberg. Spring AI allows you to get structured output (like JSON objects), connect to your own data, and much more. It makes AI a first-class citizen in the Spring ecosystem.

So, the next time you feel that spark of a creative idea, don't think it's out of reach for a Java developer. With Spring AI in your toolkit, you're more than ready to build your own magic. Happy coding!