aws api gateway & lambda: multiple endpoint/functions vs single endpoint

Question

I have an AWS api that proxies lamba functions. I currently use different endpoints with separate lambda functions:

api.com/getData --> getData
api.com/ad         


        

Answer 1

The way I see, choosing single vs multiple API is a function of following considerations:

1. Security: I think this is the biggest challenge of having a single API structure. It may be possible to have different security profile for different parts of the requirement

2. Think microservice model from business perspective: The whole purpose of any API should be serving some requests, hence it must be well understood and easy to use. So related APIs should be combined. For example, if you have a mobile client and it requires 10 things to be pulled in and out from DB, it makes sense to have 10 endpoints into a single API. But this should be within reason and should be seen in context of overall solution design. For example, if you design a payroll product, you may think to have separate modules for leave management and user details management. Even if they are often used by a single client, they should still be different API, because their business meaning is different.

3. Reusability: Applies to both code and functionality reusability. Code reusability is a easier problem to solve, ie build common modules for shared requirements and build them as libraries. Functionality reusability is harder to solve. In my mind, most of the cases can be solved by redesigning the way endpoints/functions are laid out, because if you need duplication of functionality that means your initial design is not detailed enough.

Just found a link in another SO post which summarizes better