Imagine a scenario of two different microservices. One to handle Authentication within the service, the other one takes care of User Management. They both have a concept of a User, and will talk about Users through calls to each other.
Where would the Domain model of a "User" belong though? Would they both have a different representation of what a User is on the level of the database? What about when we have a UserDTO to be used in API calls, would they both have one for their respective API's?
What is the general accepted solution for this kind of architectural issue?
Best Answer
In a Microservices architecture, each one is absolutely independent of the others and it must hide the details of the internal implementation.
If you share the model you are coupling microservices and lose one of the greatest advantages in which each team can develop its microservice without restrictions and the need of knowing how evolve others microservices. Remember that you can even use different languages in each one, this would be difficult if you start to couple microservices.
If they are too related maybe they are really one like @soru says.
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