Building a microservice

We spent quite a bit of time talking about monoliths. First, we discussed which is the best approach for you, then we spent some time showing how to deploy a monolith into Istio to get many of the benefits from it that microservices do. Now, let's dive into building and deploying a microservice. Our microservice will be pretty simple. The goal is to show how a microservice is built and integrated into an application, rather than how to build a full-fledged application based on microservices. Our book is focused on enterprise so we're going to focus on a service that:

1. Requires authentication from a specific user
2. Requires authorization for a specific user based on a group membership or attribute
3. Does something very important
4. Generates some log data about what happened

This is common in enterprise applications and the services they're built on. Most enterprises need to be able to associate actions, or decisions...