GraphQL Guru

Schema

GraphQL Federation

Using GraphQL Federation

GraphQL federation distributes schemas across microservices.

What is GraphQL Federation?

GraphQL Federation is an approach to managing GraphQL APIs that allows you to distribute your GraphQL schema across multiple microservices. This method helps in scaling the API by enabling each team to own and maintain its part of the schema. Federation improves the ability to manage complex systems by breaking them down into smaller, more manageable pieces.

Core Concepts of GraphQL Federation

There are several key concepts in GraphQL Federation:

  • Gateway: This acts as a unified entry point to the federated service, aggregating various subgraphs into a single schema.
  • Subgraph: These are individual GraphQL schemas owned by microservices. Each subgraph defines its own part of the federated schema.
  • Resolvers: Functions that handle the fetching of data for a particular field in the schema.

Setting Up a Federated GraphQL Gateway

To set up a federated GraphQL Gateway, you'll need to configure the gateway to merge schemas from multiple services. Here's a basic example of how to set up a gateway using Apollo Federation:

Defining a Subgraph Service

Each microservice in a federated architecture is responsible for a part of the schema. Here's how you can define a subgraph for the 'products' service:

Benefits of Using GraphQL Federation

GraphQL Federation offers several advantages:

  • Scalability: Allows teams to scale their GraphQL services independently.
  • Ownership: Teams can own their part of the schema, making it easier to manage and update.
  • Flexibility: New services can be added without disrupting existing ones.

GraphQL Schema

Next
Schema Validation