API Gateway is one of the essential pattern used in microservices architecture that acts as a reverse proxy to route requests from clients to multiple internal services. It also provides a single entry point for all clients to interact with the system, allowing for better scalability, security, and control over the APIs.

API Gateway handles common tasks such as authentication, rate limiting, and caching, while also abstracting away the complexity of the underlying services. Thing will be more clear when we go through a real world scenario where API Gateway can be used, so let’s do that.

Let’s assume you have a microservices-based e-commerce application that allows users to browse and purchase products. The application is composed of several microservices, including a product catalog service, a shopping cart service, an order service, and a user service.

To simplify the interaction between clients and these microservices, you can use an API gateway. The API gateway acts as a single entry point for all client requests and routes them to the appropriate microservice.

For example, when a user wants to view the product catalog, they make a request to the API gateway, which forwards the request to the product catalog service. Similarly, when a user wants to place an order, they make a request to the API gateway, which forwards the request to the order service.