Mastering Next.js 14: A Deep Dive into the App Router

Introduction to the App Router

Next.js 14 continues to refine the App Router, which introduced a new paradigm for building applications with React Server Components. This post will explore the core concepts and advanced patterns you can use.

Server Components vs. Client Components

One of the most significant changes is the default to Server Components.

• Server Components: Run on the server, have no state, and can directly access server-side resources like databases.
• Client Components: Hydrated on the client, can use hooks like useState and useEffect. Mark them with 'use client'.

// app/page.tsx (Server Component)
async function getData() {
  const res = await fetch('...');
  return res.json();
}

export default async function Page() {
  const data = await getData();
  return <h1>{data.title}</h1>;
}

Data Fetching Strategies

With the App Router, data fetching is more integrated than ever. The native fetch API is extended to automatically handle caching and revalidation.

Caching with fetch

// Revalidate every hour
fetch('...', { next: { revalidate: 3600 } });

This is a pull quote. It should stand out from the rest of the content to draw the reader's attention to a key point.

Conclusion

The App Router in Next.js 14 offers powerful tools for building performant and scalable web applications. By understanding its core principles, you can unlock a new level of developer experience.