Chat hub module

Now that we have the authentication module in place, a user can log in to our Let's Chat web application using Facebook. We still need to develop the Chat module so that the user can see their friends online and chat with them. In this section, we will develop the Chat hub module using SignalR. We have already developed a Tic-Tac-Toe game using SignalR. Hence, we are already familiar with how to develop a SignalR hub and get the communication going back and forth between clients and server, so this should be relatively easier for us. On the client side, we will make use of Razor pages. ASP.NET Core 2.0 introduced a new feature called Razor pages, which makes the coding of page-focused scenarios much easier. If you have worked on earlier versions of ASP.NET, you will have seen or heard about ASP.NET Web forms (.aspx) applications, which had web forms at the heart of development. This is more or less on the same lines in the MVC world and makes it really productive to develop...