Long story short. No, there's not a general way to design microservices. Microservices is an architectural style which operates a very high level of abstraction. This answer is extensible to any other sort fo architecture. For example, there could be monoliths that don't require 3-layers designs.
What you are looking for is named adequacy. If you consider any of the mentioned layers to be "overkill" just don't implement it. Whether is overkill or not is something to look at the requirements and the needs of each specific component of the architecture. Thankfully, Microservices are meant to provide us freedom in the design and development of these components since they don't share SDLC.
Yeah my main reason for asking this question was to make a kind of
template for microservices that I could just pop out for the business
services, but I guess that's too much of the greater good
That could be a good idea. Ultimately, Microservices architectures are populated with many services. It doesn't mean they are going to be radically different from each other. Templates can state the minimums required to be a good citizen of the system. Just take into account that there could be different technological stacks and probably you should provide templates for each of them.
The Required Standard
When you’re working through your practices and
thinking about the trade-offs you need to make, one of the core
balances to find is how much variability to allow in your system. One
of the key ways to identify what should be constant from service to
service is to define what a well-behaved, good service looks like.
What is a “good citizen” service in your system? What capabilities
does it need to have to ensure that your system is manageable and that
one bad service doesn’t bring down the whole system? And, as with
people, what a good citizen is in one context does not reflect what it
looks like somewhere else. Nonetheless, there are some common
characteristics of well-behaved services that I think are fairly
important to observe. These are the few key areas where allowing too
much divergence can result in a pretty torrid time. As Ben Christensen
from Netflix puts it, when we think about the bigger picture, “it
needs to be a cohesive system made of many small parts with autonomous
lifecycles but all coming together.” So we need to find the balance
between optimizing for autonomy of the individual microservice without
losing sight of the bigger picture. Defining clear attributes that
each service should have is one way of being clear as to where that
balance sits.
Chapter 2. The evolutionary Architect
Building Microservices - ISBN-13: 978-1491950357
by Sam Newman
