Interfaces

The schema file supports GraphQL Interfaces for modelling complex types sharing common traits. Interfaces are annotated with @query at the type level and do not affect the backing database schema, only enriching the GraphQL API queries with inline fragments.

Examples

interface MyEntity @query {
  id: ID!
  name: String
  ref: Ref
}

type Ref @entity {
  id: ID!
  name: String
  foo: Foo! @unique
  bar: Bar! @unique
} 

type Foo implements MyEntity @entity {
  id: ID!
  name: String
  ref: Ref @derivedFrom(field: "foo")
  foo: Int
}

type Bar implements MyEntity @entity {
  id: ID!
  name: String
  ref: Ref @derivedFrom(field: "bar")
  bar: Int
}

type Baz implements MyEntity @entity {
  id: ID!
  name: String
  ref: Ref
  baz: Int
}

The MyEntity interface above enables myEntities and myEntitiesConnection GraphQL API queries with inline fragments and the _type, __typename meta fields:

query {
  myEntities(orderBy: [_type_DESC, id_ASC]) {
    id
    name
    ref {
        id
        name
    }
    __typename
    ... on Foo { foo }
    ... on Bar { bar }
    ... on Baz { baz }
  }
}