Why Nextjs and Websockets hate each other

NextJS is a popular framework for building server-side rendered React applications. While it provides a great developer experience for building web applications, implementing socket communication in NextJS can be challenging and can result in unmaintainable code.

Why Socket Communication in NextJS is Difficult?

The primary reason for the difficulty in implementing socket communication in NextJS is that it's a server-side rendering framework. The server-side rendering process requires that the entire page is rendered on the server before it's sent to the client. This means that if you want to use sockets to update the page in real-time, you need to establish a connection between the server and the client. However, establishing a connection between the server and the client in NextJS is challenging because the server and the client run in separate processes.

Furthermore, NextJS uses a different approach to handling client-side code than traditional React applications. In NextJS, the client-side code is bundled and executed separately from the server-side code. This means that you can't simply include your socket code in your NextJS components, as you would in a traditional React application. Instead, you need to find a way to share the socket code between the server and the client.

5 Solutions for Socket Communication in NextJS

Use a third-party library: Advantages of using a third-party library to implement socket communication in Next.js include having access to a simple interface for establishing WebSocket connections and handling incoming messages, as well as being able to benefit from the community support and updates provided by the library. A disadvantage of this approach is that you may have to learn and integrate a new library into your application, which can add complexity and potentially slow down development time.
Use a custom server: Advantages of creating a custom server using Node.js's built-in http module include having more control over the server and being able to share socket code between the server and the client as in a traditional Node.js application. However, a disadvantage of this approach is that it may add complexity to your application, and you will need to ensure that your server is properly configured to work with Next.js.
Use a middleware: Advantages of using a middleware like express-socket.io-session include being able to easily integrate Socket.io with Express, as well as having access to a simple API for establishing socket communication. However, a disadvantage of this approach is that it may not be as flexible as using a custom server, and you will need to ensure that your middleware is properly configured to work with Next.js.
Use a hybrid approach: Advantages of using a hybrid approach include being able to take advantage of the benefits of both client-side and server-side socket communication, while minimizing their drawbacks. However, a disadvantage of this approach is that it can add complexity to your application, and you will need to ensure that both the client-side and server-side code are properly configured and integrated with Next.js.
Use a third-party service: Advantages of using a third-party service like Pusher or Firebase include not having to worry about implementing and maintaining socket communication yourself, as well as having access to a simple API for implementing real-time communication in your Next.js application. However, a disadvantage of this approach is that it may add a cost to your application, and you will need to ensure that your application is properly integrated with the third-party service.

This code creates a socket connection using the Socket.io library and listens for 'message' events. It also sends messages to the server when the user types something in the input field. This code can be used in a NextJS component to enable real-time communication with the server.

Conclusion

Socket communication in NextJS can be challenging due to the nature of server-side rendering and the separation of the client and server code. However, there are many solutions available that can help you implement socket communication in a maintainable and scalable way. By using a library, custom server, middleware, hybrid approach, or third-party service, you can enable real-time communication in your NextJS application and provide a great user experience for your users.