edge-graphql

One Graph Service with graphql federation v2 example. We're using Apollo Federation which is an open source architecture for building a distributed graph. With Apollo Federation, we're able to implement GraphQL in a microservice architecture. It’s designed to replace schema stitching and solve pain points such as coordination, separation of concerns, and brittle gateway code.

Sub Graphs

Edge GraphQL super graph is composed by the following sub graphs:

Products Domain Graph Service

Orders Domain Graph Service

Reviews Domain Graph Service

Running

Make sure that all subgraphs are running. To run the edge graphql, type:

yarn dev

or

make dev

Example

This query should fetch data from all subgraphs:

query OrdersQuery {
  orders {
    id
    customerId
    total
    items {
      product {
        id
        title
        price
        description
        reviews {
          id
          content
        }
      }
      price
      total
    }
  } 
}

FAQ

• How it works when subgraph schema changes in production? Supergraph needs to redeploy? ...

• What happens when a subgraph is down? If any subgraph is down, the supergraph application will raise an error when it starts: Error: Couldn't load service definitions for "orders" at http://localhost:4001/graphql: request to http://localhost:4001/graphql failed. When supergraph is already running and subgraph crashes for some reason, any request that it's handled by the crashed subgraph will fail.

• Is it any performance issues? A note on performance: Query Planning and Execution adds a ~10ms overhead in the worst case. This includes the compute for building the query plan, as well as the deserialization of DGS responses and the serialization of merged gateway response.

• How does it work with Relay subgraph?

• Is there any alternative for federation?
  Maybe schema stitching.

Docs

GraphQL Principle.

Apollo Federation.

Netflix API with GraphQL Federation.