What is GraphQL Federation?

GraphQL Federation is an architecture model that allows multiple GraphQL services, known as subgraphs or federated services, to be combined into a single schema or API.

This unified data graph enables clients to query and receive responses from multiple services using a single request.

Apollo, a prominent company in the GraphQL ecosystem, pioneered this concept to facilitate the seamless integration of various microservices and data sources.

Core Principles of GraphQL Federation

1. Composition: GraphQL Federation enables the composition of multiple, independently deployed GraphQL services into a single schema. This process is facilitated by the Federation Gateway, a server that communicates with each federated service, combines their respective schemas, and resolves incoming queries.
2. Separation of Concerns: Each federated service can be developed, deployed, and maintained independently, which allows teams to work autonomously and focus on their specific domains.
3. Schema Extensions: Federation enables the extension of types and fields across services, allowing for seamless data stitching and the resolution of related data from different services.
4. Query Planning: When a query is received, the gateway generates a query plan, determining the optimal…