GraphQL-在联合体内以不同类型使用相同的字段名称

Question

如果我有这样的联合类型：

union AllOnboardingQuestionTypes = StepFinal | TimeRangesQuestion | PercentQuestion | SingleSelectQuestion | MultiSelectQuestion | InformationOnly

如果某些类型的字段名称相同但类型不同（例如，答案PercentAnswer是is，float而SingleSelect的答案是a string），这是执行查询的正确方法吗？

query OnboardingQuestionsQuery {
     onboardingQuestions {
       ... on InformationOnly {
         title
         description
         questionID
         inputType
       }
       ... on StepFinal {
          title
          description
       }
       ... on TimeRangesQuestion {
          title
          description
          timePeriods {
            timePeriod
            estimatedEnd
            estimatedStart
          }
       }
       ... on SingleSelectQuestion {
         title
         description
         questionID
         inputType
         singleSelectAnswer: answer
         singleSelectOptions: options {
           value
           label
         }
       }
       ... on MultiSelectQuestion {
         title
         description
         questionID
         inputType
         multiSelectAnswer: answer
         multiSelectOptions: options
       }
       ... on PercentQuestion {
         title
         description
         questionID
         inputType
         percentAnswer: answer
         min
         max
       }
    }
}

别名对我来说似乎很麻烦，会使事情变得棘手，因为在修改数据时我必须处理脱发，我希望我可以用answer代替singleSelectAnswer。

但是当我尝试该操作时，出现以下错误：

{"errors":[{"message":"Fields \"answer\" conflict because they return conflicting types String! and [Boolean!]!. Use different aliases on the fields to fetch both if this was intentional.","locations":[{"line":64,"column":7},{"line":69,"column":7}]},{"message":"Fields \"answer\" conflict because they return conflicting types String! and Float!. Use different aliases on the fields to fetch both if this was intentional.","locations":[{"line":64,"column":7},{"line":74,"column":7}]},{"message":"Fields \"answer\" conflict because they return conflicting types [Boolean!]! and Float!. Use different aliases on the fields to fetch both if this was intentional.","locations":[{"line":69,"column":7},{"line":74,"column":7}]}]}

我是GraphQL的新手，不知道这是处理它的正确方法。在我的脑海里，我希望遵循多态性方法，但也许那不是这样做的方法。

Answer 1

这是进行查询的正确方法吗？

是的。根据当前（2018 年 6 月）的GraphQL 规范，联合受到这种方式的限制。另请参阅graphql.js上的相应问题

别名看起来很麻烦

避免这种情况的最佳方法是当返回类型不同时，模式指定不同的字段名称。