Server-side rendering with Redux for better initial load times

14 Sep 2023

In today’s web development world, performance and user experience play a crucial role in determining the success of a website or application. One of the key factors that can affect the initial load time of a page is the amount of client-side rendering that needs to take place. By adopting server-side rendering (SSR) with Redux, we can significantly improve the initial load times and provide a better user experience.

What is server-side rendering?

Server-side rendering is the process of generating the initial HTML of a webpage on the server and sending it to the client. This means that when the user requests a page, they receive a fully rendered HTML response directly from the server.

Why use server-side rendering?

The major advantage of SSR is that it allows the user to see the content of the page faster. Instead of waiting for all the JavaScript to download, parse, and execute to generate the page, SSR delivers the pre-rendered HTML immediately. This results in faster perceived load times and can greatly improve the user experience, especially on slower network connections or devices.

How does Redux fit into server-side rendering?

Redux is a predictable state container for JavaScript applications. It is commonly used with React to manage the state of an application. When using server-side rendering, we need to ensure that the initial state of the application is the same on both the server and the client.

To achieve this, we can use the [redux][1] and [react-redux][2] libraries in combination with a server-side rendering framework of our choice (e.g., Express.js).

Here is an example of how we can configure Redux for server-side rendering:

// server.js
import express from 'express';
import { renderToString } from 'react-dom/server';
import { Provider } from 'react-redux';
import { createStore } from 'redux';
import rootReducer from './reducers';
import App from './App';

const app = express();

app.get('/', (req, res) => {
  // Create a new Redux store instance with the initial state
  const store = createStore(rootReducer, {});

  // Render the App component to a string using the store context
  const html = renderToString(
    <Provider store={store}>
      <App />
    </Provider>
  );
  
  // Send the pre-rendered HTML response to the client
  res.send(`
    <html>
      <head>
        <title>Server-side Rendering with Redux</title>
      </head>
      <body>
        <div id="root">${html}</div>
        <script>
          // Inject the initial state into the client-side Redux store
          window.__PRELOADED_STATE__ = ${JSON.stringify(store.getState()).replace(/</g, '\\u003c')}
        </script>
        <script src="/client.js"></script>
      </body>
    </html>
  `);
});

app.listen(3000, () => {
  console.log('Server is running on port 3000');
});

In this example, we create a new Redux store instance on each server request, render the App component to a string using the Provider component from react-redux, and send the pre-rendered HTML response to the client. We also inject the initial state into a global variable __PRELOADED_STATE__ which we can then use on the client side to hydrate the Redux store.

Conclusion

Server-side rendering with Redux is a powerful technique that can significantly improve the initial load times of webpages. By performing the rendering on the server and sending pre-rendered HTML to the client, we can reduce the time it takes for the user to see content and provide a better user experience. With the integration of libraries like redux and react-redux, implementing server-side rendering with Redux becomes straightforward and effective.

#ServerSideRendering #Redux #WebPerformance [1]: https://redux.js.org [2]: https://react-redux.js.org