Now we're ready to run our app and let users log in through Facebook login or Google login mechanisms.
Both Facebook and Google return the ProviderKey property to identify an individual user. We can hold that info in the database and relate it to another table (such as ShoppingCart, PurchaseHistory, and so on.) This way, we can let Facebook and Google manage users, but we can still reference that user in our database system.
The beauty of ASP.NET Core Identity is that we can easily plug another system into it (such as Linkedin, Microsoft Live, GitHub, Auth0, and so on). It's only adding a library and creating an app in the authorization server system. In ASP.NET Core, we can create an empty project and turn it into a fully fledged application with identity capabilities.
Microsoft published the Microsoft.AspNetCore.Identity NuGet package (https://www...
