avoid duplicates on MongoDB using Mongoose - node.js

Question

Hi I'm new to MongoDB and Moongoose I'm trying to avoid my api's users to store on the Mongo database duplicated contact's name but seems like it's not working at all.
This is how I'm trying to do it right now the name and the phone number are mandatory and also the name must be unique otherwise it should throw an error.
const contactSchema = new mongoose.Schema({
name: {
type: String,
required: true,
unique: true
},
number: {
type: Number,
required: true
}
});
app.post('/api/persons', (request, response) => {
const body = request.body;
const person = new Contact({
name: body.name,
number: +body.number
});
person.save()
.then(saved => {
response.json(saved);
})
.catch(error => {
return response.status(400).json({
error: 'content missing'
});
});
})
If I send a post request with missing name or number it already throws an error but seems like it's not gettin the unique value validation.

Answer 1

Finally found a package that allows me to avoid duplicted entries on Mongo. I used this package following the documentation instructions:
https://github.com/blakehaswell/mongoose-unique-validator#readme
This is the code I had to write:
const uniqueValidator = require('mongoose-unique-validator');
const contactSchema = new mongoose.Schema({
name: {
type: String,
required: true,
unique: true
},
number: {
type: Number,
required: true
}
});
contactSchema.plugin(uniqueValidator);

Answer 2

the error of unique validation is weird so you can use unique-validator plugin, after that when you send a post request with missing name or number, the error is about required: true
Refer to validation
Validators are not run on undefined values. The only exception is the required validator.

Answer 3

Since both the fields(name and number) in your DB are required.
Instead of directly passing the request body to the query, you can do something like this.
const name = body.name;
const number = body.number;
if(!name || !number) {
// Return response saying either of the fields is empty.
// It's not a good practice to hit the DB with undefined values.
}
let personDetails = {
"name": name,
"contact": contact
};
const person = new Contact(personDetails);
Regarding the unique validation either you can use the unique-validator plugin as suggested by Mohammad Yaser Ahmadi or you can make a DB call to check if the name and number are unique and then hit the save method if that's is feasible for your database.
If you want both the fields name and number to be combined unique you can create Compound Index as follows:
contactSchema.index({ name: 1, number: 1 }, { unique: true });
You can read more on Compound Indexes here: https://docs.mongodb.com/manual/core/index-compound/