Using GraphQL Fragment on multiple types

问题:

If I have a set of field that is common to multiple types in my GraphQL schema, is there a way to do something like this?

type Address {
  line1: String
  city: String
  state: String 
  zip: String
}

fragment NameAndAddress on Person, Business {
  name: String
  address: Address
}

type Business {
   ...NameAndAddress
   hours: String
}

type Customer {
   ...NameAndAddress
   customerSince: Date
}

回答1:

Fragments are only used on the client-side when making requests -- they can't be used inside your schema. GraphQL does not support type inheritance or any other mechanism that would reduce the redundancy of having to write out the same fields for different types.

If you're using apollo-server, the type definitions that make up your schema are just a string, so you can implement the functionality you're looking for through template literals:

const nameAndAddress = `
  name: String
  address: Address
`

const typeDefs = `
  type Business {
     ${nameAndAddress}
     hours: String
  }

  type Customer {
     ${nameAndAddress}
     customerSince: Date
  }
`

Alternatively, there are libraries out there, like graphql-s2s, that allow you to use type inheritance.