Problem with FreeCodeCamp's "MongoDB and Mongoose - Create a Model" Challenge - mongodb

Question

I am doing FreeCodeCamp's "MongoDB and Mongoose - Create a Model" challenge. I have submitted by code. However, I am getting this error:
Creating an instance from a mongoose schema should succeed
Here are my codes:
let mongoose = require('mongoose')
mongoose.connect(uri, { useNewUrlParser: true, useUnifiedTopology: true });
let personSchema = new mongoose.Schema({
name: {type: String, required: true},
age: Number,
favoriteFoods: [String]
});
let Person = mongoose.model('Person', personSchema);
Have I made any mistake?

Answer 1

Since you are submitting this code to FCC server, you don't need to connect to db by your own. They must be having connections already made to db. You just have to provide the right implementation of Person model. IMO Since you had that line in your submission, code was breaking at that line and subsequent lines were not getting executed. Hence you were getting this error. Creating an instance from a mongoose schema should succeed
Try this -
let mongoose = require('mongoose');
let Schema = mongoose.Schema;
let personSchema = new Schema({
name: {type: String, required: true},
age: Number,
favoriteFoods: [String]
});
let Person = mongoose.model('Person', personSchema);

Answer 2

The following code worked for me after trying many different things suggested on different posts/blogs on the Internet.
require('dotenv').config();
//To-Do # 1: Install & Set up mongoose */
const mongoose = require('mongoose');
mongoose.connect(process.env.MONGO_URI);
//To-Do # 2: Create a Model
const personSchema = new mongoose.Schema({
name: { type: String, required: true },
age: Number,
favoriteFoods: [String]
});
const Person = mongoose.model('Person', personSchema);
I still could not find what was the problem as I tried to copy and paste exactly the code given in the solution to the problem suggested by free code camp and even that did not work. I was using replit and perhaps there must be some problem when the free code camp tests interact with the liver server of replit but some expert should answer the problem in detail to save time for other people.

Answer 3

It appears that the problem occurs because a code below is trying to redeclare the "Person" variable (After making it a const). If you look at the boilerplate code on Replit, there were some codes present there already and part of this code has the following:
let Person;
Simply commenting this line out worked for me.