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Last updated on Nov 1, 2023
Last updated on Aug 7, 2023
Server side rendering (SSR) is a popular technique in web development that can significantly improve the performance of your web applications. It involves generating the initial HTML of a page on the server, rather than in the client's browser. This results in faster initial load times and better search engine optimization (SEO), as search engines can crawl and index server-rendered content more easily.
In contrast to server side rendering, client side rendering involves generating the HTML of a page in the client's browser using JavaScript. While this approach can provide a more interactive user experience, it can also lead to slower initial load times and less SEO-friendly content.
React, a popular JavaScript library for building user interfaces, provides robust support for server side rendering. With React, you can build complex, dynamic web applications that are both SEO-friendly and performant. In this blog post, we'll dive deep into the world of server side rendering in React, exploring how it works, how to implement it, and the benefits and drawbacks it offers.
In a typical server side rendering setup, when a user makes a request to your web page, the server runs the React code to generate the initial HTML. This fully rendered HTML page is then sent back to the client's browser, providing a faster initial load experience.
This is in contrast to traditional client side rendering, where the server sends an almost empty HTML file with links to the JavaScript files. The browser downloads these files and runs the JavaScript code to generate the HTML content.
Implementing server side rendering in a React app involves several steps. First, you need to set up a Node server to handle incoming requests and return the server side rendered content.
Next, you'll need to modify your React components to ensure they can be rendered on the server. This typically involves replacing any browser-specific code with universal code that can run both on the server and the client.
Finally, you'll need to use the ReactDOMServer.renderToString() method to render your React components to a HTML string on the server. This HTML string can then be inserted into a HTML page and sent to the client.
The server code in a server side rendered React app is responsible for handling incoming requests and returning the rendered HTML. It typically uses a Node.js server, such as Express, and includes a route that handles all incoming requests.
The JS file, on the other hand, is where your React code lives. This file is executed on the server to generate the initial HTML, and then again on the client to "hydrate" the HTML and make it interactive.
In the next section, we'll explore the benefits and drawbacks of server side rendering in React.
One of the main benefits of server side rendering in React is improved search engine optimization. Since the initial HTML is fully rendered on the server, search engine crawlers can easily index your web pages, leading to better SEO.
Another major advantage is faster initial page load speed. With server side rendering, the user's browser receives a fully rendered HTML page from the server, which can be displayed immediately. This results in a faster initial load time, especially for users with slow internet connections or low-powered devices.
Despite its benefits, implementing server side rendering in a React app can be challenging. It requires a good understanding of both server side and client side JavaScript, and can add complexity to your codebase.
For example, you'll need to ensure your React components can be rendered on the server, which may involve replacing browser-specific code with universal code. You'll also need to manage the state of your app on both the server and the client, which can be tricky.
In addition, server side rendering can increase the load on your server, as it needs to generate the HTML for each request. This can lead to increased server costs and may require additional optimizations to ensure your server can handle the load.
Before we can start implementing server side rendering in a React app, we need to set up our development environment. This typically involves installing Node.js and npm, which are used to run our server and manage our project's dependencies.
Next, we'll need to install Express, a popular Node.js server framework. We'll use Express to handle incoming requests and return our server side rendered content.
Finally, we'll need to install React and ReactDOM, which we'll use to build our React app and render it on the server.
Once our environment is set up, we can start building our server side rendered React app. One of the easiest ways to do this is by using Create React App, a command line tool that sets up a new React project with a modern build setup.
To create a new server side rendered app with Create React App, we'll first need to create a new React app. We can do this by running the following command in our terminal:
1 npx create-react-app my-app 2
Next, we'll need to modify our new React app to support server side rendering. This involves setting up a Node server with Express, modifying our React components to be renderable on the server, and using ReactDOMServer to render our components to a HTML string.
With our server side rendered React app set up, we can now start rendering our web pages on the server.
When a user makes a request to our app, our server will run our React code to generate the initial HTML. This HTML is then inserted into a HTML document and sent back to the user's browser.
To render a React component on the server, we can use the ReactDOMServer.renderToString() method. This method takes a React element and returns a HTML string, which we can then insert into our HTML document.
Here's an example of how we might use ReactDOMServer.renderToString() in our server code:
1 const express = require('express'); 2 const ReactDOMServer = require('react-dom/server'); 3 const App = require('./App'); 4 5 const app = express(); 6 7 app.get('*', (req, res) => { 8 const htmlString = ReactDOMServer.renderToString(<App />); 9 res.send(`<!DOCTYPE html> 10 <html> 11 <head> 12 <title>My App</title> 13 </head> 14 <body> 15 <div id="root">${htmlString}</div> 16 </body> 17 </html>`); 18 }); 19 20 app.listen(3000, () => console.log('Server is running on port 3000')); 21
In this code, we're using Express to create a new server, and setting up a route that handles all incoming requests. When a request is made, we render our App component to a HTML string using ReactDOMServer.renderToString(), and send this string back to the client inside a HTML document.
Server side rendering in React is not just about rendering static HTML pages. It also involves handling dynamic components that change based on the state of your app, and serving static files such as images and CSS files.
Dynamic components in a server side rendered React app are handled in much the same way as in a client side rendered app. The main difference is that the initial state of your dynamic components is determined on the server, and then "hydrated" on the client to make them interactive.
Static files, on the other hand, are typically served by your Node server. You can use the express.static() middleware to serve static files from a directory on your server.
While server side rendering can improve the initial load time of your React app, it can also increase the load on your server, as it needs to generate the HTML for each request. This can lead to increased server costs and may require additional optimizations to ensure your server can handle the load.
One way to optimize the performance of a server side rendered React app is by implementing caching. By caching the HTML generated by your server, you can reduce the amount of work your server needs to do for each request, leading to faster page loads and reduced server costs.
Another optimization you can make is to use code splitting to reduce the size of your JavaScript bundles. This can make your app load faster, especially for users with slow internet connections.
When building a server side rendered React app, you'll often need to work with React Router and CSS files.
React Router is a popular library for adding routing to your React app. It allows you to define multiple routes for your app, and render different components based on the current URL. When using React Router in a server side rendered app, you'll need to use the StaticRouter component, which is designed to work in a server environment.
CSS files in a server side rendered React app are typically handled using CSS-in-JS libraries like styled-components or emotion. These libraries allow you to write your CSS in your JavaScript files, and can generate the CSS for your components on the server.
Server side rendering in React is not just about rendering static HTML pages. It also involves handling dynamic components that change based on the state of your app, and serving static files such as images and CSS files.
Dynamic components in a server side rendered React app are handled in much the same way as in a client side rendered app. The main difference is that the initial state of your dynamic components is determined on the server, and then "hydrated" on the client to make them interactive.
Static files, on the other hand, are typically served by your Node server. You can use the express.static() middleware to serve static files from a directory on your server.
While server side rendering can improve the initial load time of your React app, it can also increase the load on your server, as it needs to generate the HTML for each request. This can lead to increased server costs and may require additional optimizations to ensure your server can handle the load.
One way to optimize the performance of a server side rendered React app is by implementing caching. By caching the HTML generated by your server, you can reduce the amount of work your server needs to do for each request, leading to faster page loads and reduced server costs.
Another optimization you can make is to use code splitting to reduce the size of your JavaScript bundles. This can make your app load faster, especially for users with slow internet connections.
When building a server side rendered React app, you'll often need to work with React Router and CSS files.
React Router is a popular library for adding routing to your React app. It allows you to define multiple routes for your app, and render different components based on the current URL. When using React Router in a server side rendered app, you'll need to use the StaticRouter component, which is designed to work in a server environment.
CSS files in a server side rendered React app are typically handled using CSS-in-JS libraries like styled-components or emotion. These libraries allow you to write your CSS in your JavaScript files, and can generate the CSS for your components on the server.
Node.js and Express are two key tools for server side rendering in React. Node.js is a JavaScript runtime that allows you to run JavaScript on the server, while Express is a popular Node.js server framework.
In a server side rendered React app, Node.js is used to run your server code and your React code on the server. Express, on the other hand, is used to handle incoming requests and return your server side rendered content.
To get started with Node.js and Express, you can check out their official documentation. They provide a wealth of information on how to set up a Node server, how to handle requests with Express, and how to integrate with other tools and libraries.
Static site generators are another useful tool for server side rendering in React. They allow you to generate static HTML pages from your React components at build time, which can then be served by any static file server.
One popular static site generator for React is Gatsby. Gatsby allows you to build static websites using React and GraphQL, and provides a wealth of plugins and integrations to help you build high-performance, SEO-friendly websites.
Another static site generator to consider is Next.js. Next.js provides a full-featured framework for building server side rendered and statically generated React apps, and includes features like automatic code splitting, route prefetching, and hot code reloading.
In addition to Node.js, Express, and static site generators, there are several other libraries and tools that can help you with server side rendering in React.
For example, ReactDOMServer is a library provided by React that allows you to render your React components to a HTML string on the server. This is a key part of any server side rendered React app.
Another useful tool is webpack, a module bundler for JavaScript. webpack allows you to bundle your JavaScript files into a single file, which can be served by your server and loaded by the client's browser.
Server side rendering in React is a rapidly evolving field, with new tools, techniques, and best practices emerging all the time. As a React developer, it's important to stay up-to-date with these developments to ensure you're building the best possible web applications.
One trend to watch is the increasing use of static site generators for server side rendering. Tools like Gatsby and Next.js are making it easier than ever to build high-performance, SEO-friendly websites with React.
In this post, we've explored the world of server side rendering in React. We've covered the basics of server side rendering, how it works, and how to implement it in a React app. We've also looked at the benefits and drawbacks of server side rendering, and shared some tips and tricks for efficient server side rendering.
We've also explored some advanced topics in server side rendering, including handling dynamic components and static files, optimizing the performance of a server side rendered app, and working with React Router and CSS files.
Finally, we've looked at some real-world examples of server side rendering in React, and explored some tools and resources for server side rendering, including Node server, Express server, and static site generators.
As a React developer, you're probably always on the lookout for tools and resources that can help you write better code, faster. One such tool that I'd recommend is WiseGPT, a promptless Generative AI for React developers.
WiseGPT is a powerful tool that can write code in your style without a context limit. It also provides API integration by accepting Postman collection and supports extending UI in the VSCode itself.
What I love about WiseGPT is that it's not just a code generator. It's a tool that understands my coding style and helps me write better, more efficient code. It's like having a pair of extra hands that know exactly what I want to do and how I want to do it.
If you're a React developer looking to level up your coding game, I highly recommend giving WiseGPT a try. It's a game-changer!
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