Mastering API Architecture

Chapter 3. API Gateways: Ingress Traffic Management

Now that you have a good understanding of defining and testing an API, we can turn our attention to platforms and tooling that are responsible for delivering APIs to consumers in production. An API gateway is a critical part of any modern technology stack, sitting at the network “edge” of systems and acting as a management tool that mediates between a consumer and a collection of backend services.

In this chapter you will learn about the “why,” “what,” and “where” of API gateways and explore the history of the API gateway and other edge technologies. You will also explore the taxonomy of API gateways and learn how these fit into the bigger picture of system architecture and deployment models, all while avoiding common pitfalls.

Building on all of these topics, you will conclude the chapter by learning how to select an appropriate API gateway based on your requirements, constraints, and use cases.

Is an API Gateway the Only Solution?

We have frequently been asked, “Is an API gateway the only solution to getting user traffic to backend systems?” The short answer is no. But there is a bit more nuance here.

Many software systems need to route consumer API requests or ingress traffic from an external origin to an internal backend application. With web-based software systems, often the consumer’s API requests originate from an end user interacting with a backend system via a web browser or mobile app. A consumer’s requests may also ...