Server-Side Rendering (SSR) in Next.js

Server-Side Rendering (SSR) is a method of rendering web pages on the server side and sending fully-rendered HTML to the client. In Next.js, SSR can be implemented using specific methods provided in the framework, allowing for enhanced SEO and faster initial page loads.

1. What is SSR?

In traditional client-side rendering, JavaScript code is executed in the browser to render pages dynamically. However, with SSR, the server itself renders the HTML and sends it directly to the client, resulting in faster page loads for the user, especially beneficial for SEO (Search Engine Optimization) and performance.

SSR is especially beneficial for:

• SEO: Pages are easier to index as search engines receive fully rendered HTML.
• Performance: Users on slower networks can experience faster initial loads since content is pre-rendered.

2. Implementing SSR in Next.js

Next.js simplifies SSR by providing a built-in function called getServerSideProps. This function runs on the server and fetches data before rendering the page, sending the HTML to the client with the data already populated.

3. Example Code for SSR in Next.js

Let’s walk through an example of creating a Next.js page that uses SSR to render user information. Here, we use the getServerSideProps function to fetch data about a specific user from an API endpoint.

Step-by-Step Example:

// pages/user.js

import React from 'react';

// Server-side function to fetch user data
export async function getServerSideProps() {
    const res = await fetch('https://jsonplaceholder.typicode.com/users/1');
    const user = await res.json();

    return { props: { user } };
}

// Component to render user data
export default function UserPage({ user }) {
    return (
        
{user.name}
Email: {user.email}
Phone: {user.phone}

    );
}
    

In this example:

1. The getServerSideProps function runs each time the page is requested, fetching data from an API (https://jsonplaceholder.typicode.com/users/1) before the page is rendered.
2. Returning Props: The fetched user data is returned as props, which are then passed to the UserPage component.
3. The UserPage component receives the user data as props and displays the user details in HTML.

4. Benefits of SSR

SSR can provide multiple advantages, especially for content-heavy websites:

• Improved SEO: Since search engines can index fully-rendered HTML, SSR can lead to better search engine rankings.
• Faster Initial Load: Users receive a fully-rendered page initially, which reduces the time taken to see content.
• Enhanced User Experience: Pages load faster for users on slower networks, leading to a smoother experience.

5. When Not to Use SSR

While SSR is beneficial in many scenarios, it may not always be the best choice:

• For pages that update frequently or have real-time data requirements, SSR can create additional server load.
• Pages where SEO is not critical, such as authenticated user dashboards, may not need SSR.
• SSR can increase server resource usage due to rendering each request on the server, which may lead to higher costs.

6. Key Considerations for Using SSR

Here are some best practices to consider when implementing SSR:

• Use Caching: For content that doesn’t need to be updated frequently, caching the server-rendered HTML can save resources and reduce server load.
• Combine with Static Generation: For some pages, consider Incremental Static Regeneration (ISR) to generate pages at build time or at specified intervals.
• Handle Sensitive Data Carefully: Avoid sending sensitive data through SSR as it could potentially be exposed to unauthorized users.

7. Conclusion

Server-Side Rendering in Next.js is a powerful tool for improving performance and SEO by rendering pages on the server. Implementing SSR with getServerSideProps is straightforward, and it can significantly enhance the user experience by providing faster, pre-rendered content. However, it is essential to evaluate its fit for each page, especially for dynamic, frequently updated content.

With this setup, you can take full advantage of Next.js's SSR capabilities, balancing between dynamic data and enhanced SEO.