I've been doing a ton of research on Microservices however I cannot find a single piece of code that is written for an API gateway. I understand that between the clients and services you would have an the API Gateway which allows a client to make 1 requests over IoT to the gateway and then the gateway can make many requests internally to services which then build up a response. Now from an article on NGINX
The API Gateway is responsible for request routing, composition, and protocol translation.
use case
Suppose we support 2 clients. Android and an Angular App (browser) and let's make a tangible user story that the client is an online shopping store.
the shopping store would then have different services broken out into servers and each service could be built on a different platform/language with a different database. They are completely self contained so that they can scale in the cloud really quickly without having to scale the entire application. If there is some intense Algorithm that needs to run for payment. Then the payment services can quickly spin up a few more servers to balance the load and decrease user wait time.
but that could be written in Java which could have a HTTP/REST exposed api to be consumed. However what if it's written in say c++/Golang/Node it doesn't really matter what language, but instead of exposing their api via HTTP it's by a different protocol what would that mean on the api gateway - how would it handle the response?
the client goes and makes a request to the home page where we have 3 things loaded
- shopping cart
- list view of shoppings items
- current specials
the client would only make 1 request to the api gateway let's say to apigateway/apiv1/home to the api gateway which then would have 3 requests to the services so
- serviceShopping/apiv1/shoppingList
- serviceCart/apiv1/cart
- serviceSpecial/apiv1/specials
at this point the 3 services could be written in a different language and use a different protocol. How would those 3 services be requested and on the response back to the client (a single response) how would it be concatenated? json object with a specific schema? this is where I get confused...
sorry for the long post it's a simple question I think, but I needed to setup something I can conceptualize with and explain.
