payloads-are-unions.md

Payloads are unions of a success type and one or more error types (payloads-are-unions)

A mutation payload must contain a unique success object type with the suffix Success, the base error type BaseUserError, and zero or more specific error types.

Rule Details

Autofixer not available.

Examples of incorrect code for this rule:

type Mutation {
  sampleMutation: SampleMutationPayload
}

type SampleMutationPayload {
  result: String
}

type Mutation {
  sampleMutation: SampleMutationPayload
}

union SampleMutationPayload = String | BaseUserError

type Mutation {
  sampleMutation: SampleMutationPayload
}

union SampleMutationPayload = MutationSuccess | Int

Examples of correct code for this rule:

type Mutation {
  register(input: RegisterInput!): RegisterPayload
}

union RegisterPayload =
    RegisterSuccess
  | BaseUserError
  | InvalidEmailError
  | PasswordTooWeakError