How should i connect Schema models in Mongoose?

Question

i want to make a User, Post and comment. connect them together and when i create a Post, it should be connected to one of my users. I don't know why i get an unusual error. Error:

ID cannot represent value: <Buffer 5e 9b f1 3e e9 49 61 38 fc 1a 6f 59>

these are all of my code so if you know whats my problem please help me fix it. Thanks

typeDefs:

import { gql } from 'apollo-server-express';

export const typeDefs = gql`

    type User {
        id: ID!
        name: String!
        email: String!
        age: Int
        posts: [Post!]!
        comments: [Comment!]!
    }

    type Post {
        id: ID!
        title: String!
        body: String!
        published: Boolean!
        author: User!
        comments: [Comment!]!
    }

    type Comment {
        id: ID!
        text: String!
        author: User!
        post: Post!
    }
`

UserSchema:

import mongoose, { mongo } from 'mongoose';

const userSchema = new mongoose.Schema({
    name: {
        type: String,
        required: true
    },
    email: {
        type: String,
        required: true
    },
    age: {
        type: Number,
        required: false
    },
    posts: [
        {
            type: mongoose.Schema.Types.ObjectId,
            ref: 'Post'
        }
    ],
    comments: [
        {
            type: mongoose.Schema.Types.ObjectId,
            ref: 'Comment'
        }
    ]
});

module.exports = mongoose.model('User',userSchema);

PostSchema:

import mongoose from 'mongoose';

const postSchema = new mongoose.Schema({
    title: {
        type: String,
        required: true
    },
    body: {
        type: String,
        required: true
    },
    published: {
        type: Boolean,
        required: true
    },
    author: {
        type: mongoose.Schema.Types.ObjectId,
        ref: 'User'
    },
    comments: [
        {
            type: mongoose.Schema.Types.ObjectId,
            ref: 'Comment'
        }
    ]
});

module.exports = mongoose.model('Post',postSchema);

CommentSchema:

import mongoose from 'mongoose';

const commentSchema = new mongoose.Schema({
    text: {
        type: String,
        required: true
    },
    author: {
        type: mongoose.Schema.Types.ObjectId,
        ref: 'User'
    },
    post: {
        type: mongoose.Schema.Types.ObjectId,
        ref: 'Post'
    }
});

module.exports = mongoose.model('Comment',commentSchema);

Resolver:

import Users from './models/User';
import Posts from './models/Post';
import Comments from './models/Comment';


export const resolvers = {
    Mutation: {
        createUser: async (parent, args, context, info) => {
            const user = new Users(args);
            await user.save();

            return user;
        },
        createPost: async (parent, { title, body, published, author }, context, info) => {
            const user = await Users.findById(author);

            if (!user) {
                console.log("User not found")
            }
            console.log(user)

            const post = new Posts({ title, body, published, author: user.id });
            await post.save();

            user.posts.push(post);
            await user.save();

            return post;
        }
    }
}

Answer 1

I have found the solution and you should use type: mongoose.Schema.Types.ObjectId and ref: 'Comment' and after that inside resolvers you should use population .