Server-Side Rendering (SSR) is a powerful feature of Next.js that enables the rendering of web pages on the server rather than on the client side. SSR can significantly improve the performance and search engine optimization (SEO) of your application by delivering fully-rendered pages to the client. In this blog, we'll explore what SSR is, its benefits, and how to implement it in Next.js.

What is Server-Side Rendering (SSR)?

Server-Side Rendering refers to the process of rendering web pages on the server and sending the fully rendered HTML to the client. Unlike Client-Side Rendering (CSR), where the browser renders the page using JavaScript, SSR generates the HTML on the server. This approach can improve the initial load time of the application and make it more SEO-friendly.

Benefits of SSR

1. Improved SEO:

   • Search engines can easily crawl and index the fully-rendered HTML pages, leading to better SEO performance.

2. Faster Initial Load:

   • Since the HTML is pre-rendered on the server, the initial load time is reduced, providing a better user experience.

3. Better Performance on Low-Powered Devices:

   • SSR offloads the rendering process to the server, which can be beneficial for users on low-powered devices or slow networks.

Implementing SSR in Next.js

Next.js makes it straightforward to implement SSR in your application using the getServerSideProps function. This function allows you to fetch data and render the page on the server at request time.

Example: Implementing SSR

Let's create a simple example to demonstrate SSR in Next.js. We'll build a page that fetches and displays user data from an API.

1. Set Up Your Project

Ensure you have a Next.js project set up. If not, create a new one:

npx create-next-app ssr-example
cd ssr-example

2. Create a Page with SSR

Create a new file called pages/users.js:

touch pages/users.js

Add the following content to pages/users.js:

// pages/users.js
import React from 'react';

const Users = ({ users }) => {
  return (
    <div>
      <h1>Users List</h1>
      <ul>
        {users.map(user => (
          <li key={user.id}>
            {user.name} - {user.email}
          </li>
        ))}
      </ul>
    </div>
  );
};

export const getServerSideProps = async () => {
  const res = await fetch('https://jsonplaceholder.typicode.com/users');
  const users = await res.json();

  return {
    props: {
      users,
    },
  };
};

export default Users;

In this example:

• The getServerSideProps function fetches the user data from the API at request time.

• The users data is passed as props to the Users component.

• The Users component renders the list of users.

3. Run the Development Server

Start the development server:

npm run dev

Navigate to http://localhost:3000/users to see the list of users rendered on the server.

SSR vs. Static Site Generation (SSG)

Next.js supports both SSR and Static Site Generation (SSG). It's important to choose the appropriate rendering method based on your application's requirements:

• SSR is suitable for pages that require dynamic data fetching at request time, such as personalized content, real-time data, or user-specific information.

• SSG is suitable for pages with static content that doesn't change frequently, such as blog posts, marketing pages, and documentation.

Advanced SSR Features in Next.js

Next.js offers several advanced features for SSR, including:

1. Data Caching:

• Implement caching strategies to improve the performance of your SSR pages.

2. API Routes:

• Use Next.js API routes to handle server-side logic and data fetching.

3. Middleware:

   • Use middleware to manage authentication, logging, and other server-side logic.

4. Error Handling:

   • Implement error handling to manage API failures and other issues gracefully.

Explore the official Next.js documentation on SSR to learn more about advanced SSR techniques and best practices. Happy coding!