Our last candidate is the user authentication microservice that would validate the user credentials of customers who log into our book store. The sole purpose of this microservice is to confirm whether or not the provided credentials are correct in order to restrict unauthorized access. This seems pretty simple for a microservice; however, we have to remember the fact that making this functionality a part of any other microservice would impact more than one business functionality when you decide to change your authentication mechanism. The change may come in form of using JWT tokens being generated and validated based on the OAuth 2.0 authorization framework and OpenID Connect 1.0 authentication.
The following is the final ...
