Express graphql mutation giving empty result after creating user

Question

server:

const { ApolloServer, gql } = require("apollo-server-express");
const express = require("express");
const mongoose = require("mongoose");
const { userResolvers } = require("./resolvers");
const { typeDefs } = require("./typeDefs");

const startServer = async () => {
await mongoose.connect("mongodb://localhost:27017/school", {
    useNewUrlParser: true,
});

const server = new ApolloServer({
    typeDefs,
    userResolvers,
});
await server.start();

const app = express();

server.applyMiddleware({ app });

app.listen({ port: 4000 }, () =>
    console.log(`🚀 Server ready at http://localhost:4000${server.graphqlPath}`)
);
};

startServer();

resolver

const User = require("./models/userModel").Users;
const userResolvers = {
    Mutation: {
        addUser: (parent, args) => {
        let User = new User({
            name: args.name,
            email: args.email,
            password: args.password,
            otp: args.otp,
        });
            return User.save();
        },
    },
};

module.exports = { userResolvers };

typedefs

const { gql } = require("apollo-server-express");
const typeDefs = gql`
type User {
    id: ID!
    name: String!
    email: String!
    password: String!
    otp: Float!
}
type Mutation {
    addUser(name: String!, email: String!, password: String!, otp: Int!): User
    updateUser(
    name: String!
    email: String!
    password: String!
    otp: Int!
    ): User
    deleteUser(id: ID!): User
}
`;

module.exports = { typeDefs };

here is my graphql code. Here i am trying to create user. But when i am creating a user in graphql it is sending null as response It is not thowing any error so it is unclear for me .

Please take a look what can be the error I have attached the screenshot also

Answer 1

Your local definition of User

let User = new User(...);

overwrites the global definition

const User = require("./models/userModel").Users;

This should lead to an exception

Cannot access 'User' before initialization

in the addUser function, which probably causes the null response.

Use a different name for the local definition, e.g., in lower case:

let user = new User({
  name: args.name,
  email: args.email,
  password: args.password,
  otp: args.otp,
});
return user.save();