GraphQL and Schema Federation

In a microservices architecture, different services are responsible for different parts of the application. For example, an e-commerce platform might have separate services for products, customers, orders, payments, and reviews. Each service exposes its own APIs, allowing other services or applications to access its functionality.

However, this creates an interesting challenge. Suppose a mobile application needs to display a product page containing the product name, price, inventory availability, and customer reviews. With traditional REST APIs, the application might need to call several endpoints to collect all this information.

What if the client could request exactly the data it needs through a single API? This is where GraphQL becomes useful.

And when multiple microservices need to contribute data to the same GraphQL API, Schema Federation provides a way to combine their schemas into one unified interface. Let's understand how these technologies work and where they fit into microservices architecture.