29-Route-Handlers.md

Route Handlers in Next.js

Route handlers in Next.js allow you to create custom request handlers for your routes, enabling you to build RESTful endpoints directly within your Next.js application. This feature provides full control over the response without the need for a separate server.

Key Features of Route Handlers

• RESTful Endpoints: Unlike page routes, which respond with HTML content, route handlers enable you to create endpoints that can return JSON or other data formats, making them ideal for building APIs.

• No Separate Server Required: Route handlers eliminate the need to configure a separate server, simplifying the development process.

• External API Requests: They are great for making external API requests, allowing you to fetch data server-side and return it to the client.

• Server-Side Execution: Route handlers run server-side, ensuring sensitive information like private keys remains secure and never gets exposed to the browser.

• API Routes Equivalent: In the Page Router, route handlers serve the same purpose as API routes, providing a seamless way to handle server-side logic.

File Structure and Precedence

• route.js / route.ts: If you have a route.js or route.ts file in the same app directory as a page.js or page.tsx, the route handler file will take precedence. This means that requests to that route will be handled by the route handler instead of rendering a page.

Example Usage

Suppose you want to create a route handler for a /api/data endpoint:

1. Create a Route Handler: In the app/api/data directory, create a route.js or route.ts file.

// app/api/data/route.js

export async function GET(request) {
    const data = { message: 'Hello, World!' };
    return new Response(JSON.stringify(data), {
        headers: { 'Content-Type': 'application/json' },
    });
}

2. Access the Endpoint: You can now access the /api/data endpoint, and it will respond with the JSON data defined in the route handler.

Benefits

• Security: By running server-side, route handlers keep sensitive operations secure.
• Flexibility: They provide flexibility in handling different types of requests and responses.
• Integration: Easily integrate with external APIs and services.

Route handlers in Next.js offer a powerful way to manage server-side logic, enabling you to build robust and secure applications without the complexity of a separate server setup.