This is an exercise and understand the clean architecture concept
Reference repository: https://github.com/bxcodec/go-clean-arch
Reference architecture design concept: https://herbertograca.com/2017/11/16/explicit-architecture-01-ddd-hexagonal-onion-clean-cqrs-how-i-put-it-all-together/ https://herbertograca.com/2017/07/03/the-software-architecture-chronicles/
GRPC reference: https://medium.com/@amsokol.com/tutorial-how-to-develop-go-grpc-microservice-with-http-rest-endpoint-middleware-kubernetes-daebb36a97e9