I'm working on a company project where the UI interacts with multiple different microservices instead of a single fronting api microservice. Is it the right architecture? We also have an Authorization Server (Keycloak) along with all the microservices.
When I asked this question why UI is hitting APIs all over different microservices instead of a single fronting microservice, the API Team responded that the Authorization Server (Keycloak) is already another microservice, so UI has to cater to two different microservices in any case, hence it doesn't matter to cater to other microservice too.
They responded that they follow Hexagonal Architecture, I skimmed through it and didn't find anything related to not having a single fronting microservice/or the UI can hit many microservices.
Am I missing something? Can you guys help me with some good documentation to understand this ?