Static Generation (SSG) in Next.js: Building Fast and Scalable Websites

Static Generation (SSG) is one of the most powerful features of Next.js, allowing you to pre-render pages at build time and serve them as static HTML files. This results in faster load times, better performance, and improved SEO. In this article, we’ll explore how Static Generation works in Next.js, how to implement it, and why it’s a game-changer for modern web development.

What is Static Generation?

Static Generation is a technique where pages are pre-rendered at build time and served as static HTML files. This means that the server doesn’t need to render pages on every request, resulting in faster load times and better performance. Static Generation is ideal for content that doesn’t change often, such as blogs, documentation, or marketing pages.

How Static Generation Works in Next.js

In Next.js, Static Generation is implemented using the getStaticProps and getStaticPaths functions. These functions allow you to fetch data at build time and generate static HTML files for each page.

Using getStaticProps

The getStaticProps function is used to fetch data for a page at build time. It returns an object with the props key, which contains the data to be passed to the page component.

// pages/blog/[slug].js
export async function getStaticProps({ params }) {
  const res = await fetch(`https://api.example.com/posts/${params.slug}`);
  const post = await res.json();

  return {
    props: {
      post,
    },
  };
}

export default function BlogPost({ post }) {
  return (
    <div>
      <h1>{post.title}</h1>
      <p>{post.content}</p>
    </div>
  );
}

In this example, the getStaticProps function fetches data for a blog post based on the slug parameter and passes it to the BlogPost component.

Using getStaticPaths

The getStaticPaths function is used to generate static paths for dynamic routes. It returns an object with the paths key, which contains an array of paths to be pre-rendered, and the fallback key, which determines how to handle paths that are not pre-rendered.

// pages/blog/[slug].js
export async function getStaticPaths() {
  const res = await fetch('https://api.example.com/posts');
  const posts = await res.json();

  const paths = posts.map((post) => ({
    params: { slug: post.slug },
  }));

  return {
    paths,
    fallback: false,
  };
}

export async function getStaticProps({ params }) {
  const res = await fetch(`https://api.example.com/posts/${params.slug}`);
  const post = await res.json();

  return {
    props: {
      post,
    },
  };
}

export default function BlogPost({ post }) {
  return (
    <div>
      <h1>{post.title}</h1>
      <p>{post.content}</p>
    </div>
  );
}

In this example, the getStaticPaths function generates static paths for all blog posts, and the getStaticProps function fetches data for each post.

Benefits of Static Generation

Static Generation offers several benefits:

• Faster Load Times: Static pages are pre-rendered and served as HTML files, resulting in faster load times.
• Better Performance: Since the server doesn’t need to render pages on every request, performance is improved.
• Improved SEO: Static pages are easier for search engines to crawl and index, improving SEO.
• Scalability: Static pages can be served by a CDN, making it easier to scale your application.

Secrets and Hidden Facts

• Incremental Static Regeneration (ISR): Next.js supports ISR, which allows you to update static pages after they’ve been built, without rebuilding the entire site.
• Fallback Pages: Use the fallback option in getStaticPaths to generate pages on-demand.
• Custom 404 Pages: Create a 404.js file in the pages directory to customize the 404 error page for static routes.

Conclusion

Static Generation is a powerful feature in Next.js that allows you to pre-render pages at build time, resulting in faster load times, better performance, and improved SEO. Whether you’re building a blog, a documentation site, or a marketing page, Static Generation provides the tools and flexibility you need to create fast and scalable websites.