Custom Rate Limiting for Microservices

API providers use rate limit design patterns to enforce API usage limits on their clients. It allows API providers to offer reliable service to the clients. This also allows a client to control its API consumption. Rate limiting, being a cross-cutting concern, is often implemented at the API Gateway fronting the microservices. 

There are a number of API Gateway solutions that offer rate-limiting features. In many cases, the custom requirements expected of the API Gateway necessitate developers to build their own API Gateway. The Spring Cloud Gateway project provides a library for developers to build an API Gateway to meet any specific needs. In this article, we will demonstrate how to build an API Gateway using the Spring Cloud Gateway library and develop custom rate limiting solutions.

Source : https://dzone.com/articles/rate-limiting-for-microservices