tRPC กับตัวจัดเส้นทางแอปของ Next.js

Welcome to a new era of web development with the Next.js App Router! This lesson will guide you through integrating tRPC into this powerful architecture.

The App Router introduces new paradigms like Server Components and Client Components. tRPC helps you maintain end-to-end type safety across these different rendering environments.

Before diving into tRPC, let's quickly recap the App Router's core concepts:

• Server Components: Rendered on the server, ideal for data fetching and static content. They don't have state or interactivity.
• Client Components: Rendered on the client, enabling interactivity, state, and browser APIs. They are marked with 'use client';.

tRPC plays a key role in making data fetching type-safe, regardless of whether you're in a Server or Client Component.

To integrate tRPC with the Next.js App Router, you'll use the @trpc/next/app-router adapter. This package provides utilities specifically designed for this environment.

It handles the nuances of calling tRPC procedures from both Server Components (direct calls) and Client Components (via React Query hooks).

First, you need to expose your tRPC API routes within the app directory. This typically involves creating a route.ts file (e.g., app/api/trpc/[trpc]/route.ts).

The adapter helps configure your tRPC server to work seamlessly with Next.js API routes, handling incoming requests and routing them to your tRPC procedures.

One of the biggest advantages of the App Router is fetching data directly in Server Components. With tRPC, this means you can call your backend procedures without any client-side JavaScript.

You'll create a special server-side tRPC client that allows you to call procedures directly, similar to calling a function, all while maintaining type safety.

Here's how you can fetch data using tRPC directly inside a Next.js Server Component (e.g., app/page.tsx). Notice there are no hooks used here.

For Client Components, you'll still need to set up a client-side tRPC provider. This is typically done in your root layout (e.g., app/layout.tsx) by wrapping your app with a 'use client'; component that provides the tRPC client.

This provider makes tRPC's React Query hooks available to all Client Components.

Inside a Client Component, you'll use tRPC's React Query hooks (like useQuery for fetching or useMutation for modifying data) just as you would in a traditional React app.

Remember to mark your component with 'use client'; at the top of the file to ensure it runs on the client.

This example shows a Client Component (e.g., app/client-page/page.tsx) fetching data using tRPC's useQuery hook. This component would be rendered client-side.

When should you fetch data in a Server Component versus a Client Component?

• Server Components: Ideal for initial data loads, static content, and data that doesn't need client-side re-fetching or interactivity. Reduces client bundle size.
• Client Components: Necessary for interactive features, real-time updates, and data that changes based on user input. Utilizes React Query's caching and re-fetching benefits.

Often, a hybrid approach yields the best performance and user experience.

Great job! You've learned how to integrate tRPC with the Next.js App Router.

• tRPC provides end-to-end type safety for both Server Components and Client Components.
• Use a server-side tRPC client for direct data fetching in Server Components.
• Use React Query hooks (via a client-side provider) for interactive data fetching in Client Components.
• Choosing between server and client fetching depends on your performance and interactivity needs.

This hybrid approach allows you to build robust, type-safe Next.js applications!