How to fix the “Name of the mongoose Model” is not a constructor in graphql when mutating

问题

Mutating data in the graphql playground says the message of Message: Student is not a constructor Error: "TypeError: Student is not a constructor" Student is my Mongoose Model.

I've tried reinstalling my node_modules, searching some fix on the github.

This is my Mutation Function

 addStudent: async (
      root,
      { studentId, firstName, lastName, email, password },
      { Student }
    ) => {
      const newStudent = await new Student({
        studentId,
        firstName,
        lastName,
        email,
        password
      }).save();
      return newStudent;
    }

and this is my Mongoose Model

const mongoose = require("mongoose");
const Schema = mongoose.Schema;

const StudentSchema = new Schema({
  studentId: {
    type: String,
    required: true
  },
  firstName: {
    type: String,
    required: true
  },
  lastName: {
    type: String,
    required: true
  },
  // sectionId: {
  //   type: [Schema.Types.ObjectId],
  //   ref: "Section",
  //   nullable: true
  // },
  email: {
    type: String,
    required: true
  },
  password: {
    type: String,
    required: true
  },
  createdDate: {
    type: Date,
    default: Date.now
  }
});

module.exports = mongoose.model("Student", StudentSchema);

The student should be created, but that error pops up with that message.

回答1:

Await working on promise but here you are passing student object so it returns Student is not a constructor

const newStudent = await new Student({
        studentId,
        ....
      }).save();

Instead, you can do this

1) create student object using append

const newStudent = new Student({})
newStudent.studentId = studentId
newStudent.firstName = firstName
newStudent.lastName = lastName
newStudent.email = email
newStudent.password = password

2) Create student object using constructor

const newStudent = new Student({ 
    studentId,
    firstName,
    lastName,
    email,
    password
})

and save using promise async and await

  await newStudent.save()

const newStudent = await Student.create({
    studentId,
    firstName,
    lastName,
    email,
    password
})

回答2:

Fixed! I should have provided query variables rather than manual typing on the graphql mutation

来源：https://stackoverflow.com/questions/55474130/how-to-fix-the-name-of-the-mongoose-model-is-not-a-constructor-in-graphql-when

标签

mongoose

graphql

apollo-server