了解GraphQL/Sangria-Graphql中服务器端的指定字段

Question

当客户机发送请求时，我想知道客户机请求的数据字段是什么。例如

{
  user {
    name
    address
  }
}

在上面的请求中，客户端请求了用户的name字段和地址字段。在执行查询时，我如何知道/获得桑格利亚酒-graql服务器中的这些指定字段，即名称和地址？

Answer 1

您必须在resolve（）中使用4th参数

resolve: (obj, args, auth, fieldASTs) => {
    /* all your fields are present in selections
       please check the fieldASTs JSON path it may vary if you are using relay
                                                                connections */
  const requiredFields = fieldASTs.fieldNodes[0].selectionSet.selections.map(
      (set) => set.name.value
   );
  // requiredFields will contain the name and address
}
/* fieldASTs contains fieldNames, fieldNodes and every details about your Schema 
 you can get your specified fields inside fieldNodes like */