I am working to create a serverless REST API via Firebase Cloud Functions, which seems to work well but the examples and documentation all seem to use a monolithic solution, since they use the Express framework and essentially map the root http request to the Express app, then let it handle the routing. I understand that this is because the Firebase Hosting platform does not have the ability to handle http verbs.
My expectation was that a serverless / FaaS approach would have a function for each endpoint, making for easy updates in future since there's no need to update the whole app, just that single service - i.e. a more functional approach.
What am I missing here? Why is the approach to use a single function to contain an express app? Doesn't this defeat the purpose of a serverless / Cloud Functions approach? And is there any other way of doing this?