Creating an API Endpoint using Bun

🎯What is Bun ?

Bun is a JavaScript runtime.It is an attempt to overcome the limitations of Node. js back-end development setup with a separate front-end using React, Vue, or Angular.

Unlike Node. js, Bun does not depend on npm and doesn't need any other dependencies to function. Instead, it features a built-in standard library containing support for various protocols and modules, such as environment variables, HTTP, websocket, file system, etc.

🛠️ Preparing Your Environment

⚙️Step 1: Install Bun

If you have not installed Bun yet then you can do it by running the following command in your terminal:

powershell -c "irm bun.sh/install.ps1 | iex"

⚙️Step 2: Create a New Project

Create a new folder for your project.

mkdir BarterX
cd BarterX

⚙️step 3: Intialize your project

Run the following command to initialize your Bun project:

bun init

This command will set up the neccessary files for your project.

✍️ Creating API Endpoints :

Now the enviroment has been set up let’s create simple API endpoint.

now open vs code and create index.

Bun.serve({
  fetch(req) {
    const url = new URL(req.url);

    // Create a simple GET endpoint
    if (url.pathname === "/api/hello" && req.method === "GET") {
      return new Response(JSON.stringify({ message: "Hello, Bun!" }), {
        status: 200,
        headers: { "Content-Type": "application/json" },
      });
    }

    // Return 404 for other routes
    return new Response("Not Found", { status: 404 });
  },
});

// Log server information
console.log("Server is running at http://localhost:3000");

🧐 Explanation of the Code

1. Port Customization:

   • Use process.argv to get the port number from the command line.

   • Defaults to 3000 if no port is specified.

2. The serve Function:

   • Tells Bun to create an HTTP server.

   • Handles incoming requests using the fetch function.

3. Request Handling:

   • Checks if the URL matches /api/hello with a GET request.

   • Sends back a greeting if matched.

   • Returns a 404 error for other routes.

🖥️ Running Your API

To run your API, execute the following command in your terminal:

bun run index

Test it by visiting http://localhost:3000/api/hello in your browser.

{
  "message": "Hello, Bun!"
}

If no port is specified, the server defaults to port 3000.

🔗Why Use Bun for APIs?

1. Blazing Performance:

   • Built for speed with Zig and an optimized runtime design.

2. Simplicity:

   • Native HTTP server removes the need for additional libraries like Express.

3. All-in-One Tool:

   • Combines a runtime, bundler, and package manager to streamline development.

🎯Conclusion

Bun makes creating lightweight, high-performance APIs a breeze. From native routing to JSON parsing, Bun simplifies modern web development. Whether you’re building a simple app or a production-ready system, Bun’s features make it a top choice.