为什么我不能解构 'input'，我怎样才能得到我在请求中传递的 "title"？

Question

声明类型定义


const typeDefs = gql`
    type Todo {
        _id: ID,
        title : String, 
        done : Boolean
    }
    type QueryTodo {
        todos : [Todo]
    }
    
    input TodoInput {
        title : String
    }
    
    type Query {
        todos : [Todo]
    }
    
    type Mutation{
        createTodo(input: TodoInput): Todo
    }

`;
export {typeDefs}

然后在解析器中我声明了密钥突变。下面是我的解析器代码

import {Todo} from "../../DB/Models/Todo";


const resolvers = {
    Query:{
        todos:async()=>{
            return await Todo.find()
        }
    },
    Mutation: {
        createTodo : ({input}) => {
            console.log(input)
            return {_id:"12312321",title:input,done:false}
        }
    }
}
export {resolvers}

当我尝试发出请求时出现错误

mutation {
  createTodo(input: {
   title:"string"
  }) {
    _id
  }
}

我得到的回复是

“错误”：[ { "message": "无法解构 'undefined' 的属性 'input'，因为它未定义。", “地点”：[ { “线”：2， “列”：3 } ], “小路”： [ “创建待办事项” ], “扩展”：{ “代码”：“INTERNAL_SERVER_ERROR”， “例外”： { “堆栈跟踪”：[

如何获取我在请求中传递的参数“title”

Answer 1

参见https://graphql.org/learn/execution/#root-fields-resolvers：

A resolver function receives four arguments:

obj The previous object, which for a field on the root Query type is often not used.

args The arguments provided to the field in the GraphQL query.

context A value which is provided to every resolver and holds important contextual information like the currently logged in user, or access to a database.

info A value which holds field-specific information relevant to the current query as well as the schema details

第一个参数将是 Mutation 解析器架构的 root 值 - 如果您没有通过任何解析器，显然 undefined。要访问（和解构）查询传递的参数，请使用第二个参数。

为什么我不能解构 'input'，我怎样才能得到我在请求中传递的 "title"？

Why i cannot destructure 'input' and how can i get "title" which i pass in request?

javascript

graphql

graphql-js