12In this chapter, we are going to continue to develop our Q&A app. Wouldn't it be great if, when a user was on the question page, any new answers were automatically added to the page without the user having to manually refresh the page? Well, this is exactly what we are going to do in this chapter.

We are going to use a technology called SignalR to implement this feature by creating a real-time API. We'll start this chapter by understanding what SignalR is, how it differs from a REST API, and the benefit it brings. Then, we'll add a real-time API to our ASP.NET backend, thereby creating a SignalR hub. Toward the end of this chapter, we'll interact with the SignalR real-time API from our frontend React app.

In this chapter, we'll cover the following topics:

• Understanding the benefits of SignalR
• Creating a SignalR hub
• Pushing data to SignalR clients from an API controller 
• Creating the SignalR real-time API endpoint 
• Interacting with the SignalR real-time API from React