API Gateway
An API Gateway is a server that acts as an entry point for client requests to a set of backend microservices or APIs, handling tasks like request routing, composition, and protocol translation. It centralizes cross-cutting concerns such as authentication, rate limiting, monitoring, and caching, simplifying client interactions and improving security and performance. This pattern is essential in microservices architectures to manage API complexity and provide a unified interface.
Developers should learn API Gateway patterns when building or maintaining microservices-based systems to decouple clients from service implementations and enforce consistent policies across APIs. It's particularly useful for handling authentication/authorization, load balancing, request aggregation, and API versioning in distributed environments. Use cases include e-commerce platforms, mobile backends, and enterprise integrations where multiple services need a single access point.