How to reference another schema in my Mongoose schema? - node.js

Question

I'm building a Mongoose schema for a dating app.
I want each person document to contain a reference to all the events they've been to, where events is another schema with its own models in the system. How can I describe this in the schema?
var personSchema = mongoose.Schema({
firstname: String,
lastname: String,
email: String,
gender: {type: String, enum: ["Male", "Female"]}
dob: Date,
city: String,
interests: [interestsSchema],
eventsAttended: ???
});

Answer 1

You can do so by using Population
Population is the process of automatically replacing the specified
paths in the document with document(s) from other collection(s). We
may populate a single document, multiple documents, plain object,
multiple plain objects, or all objects returned from a query.
Suppose your Event Schema is defined as follows:
var mongoose = require('mongoose')
, Schema = mongoose.Schema
var eventSchema = Schema({
title : String,
location : String,
startDate : Date,
endDate : Date
});
var personSchema = Schema({
firstname: String,
lastname: String,
email: String,
gender: {type: String, enum: ["Male", "Female"]}
dob: Date,
city: String,
interests: [interestsSchema],
eventsAttended: [{ type: Schema.Types.ObjectId, ref: 'Event' }]
});
var Event = mongoose.model('Event', eventSchema);
var Person = mongoose.model('Person', personSchema);
To show how populate is used, first create a person object,
aaron = new Person({firstname: 'Aaron'})
and an event object,
event1 = new Event({title: 'Hackathon', location: 'foo'}):
aaron.eventsAttended.push(event1);
aaron.save(callback);
Then, when you make your query, you can populate references like this:
Person
.findOne({ firstname: 'Aaron' })
.populate('eventsAttended') // only works if we pushed refs to person.eventsAttended
.exec(function(err, person) {
if (err) return handleError(err);
console.log(person);
});

Answer 2

To reference the ObjectId of one table in another table refer below code
const mongoose = require('mongoose'),
Schema=mongoose.Schema;
const otpSchema = new mongoose.Schema({
otpNumber:{
type: String,
required: true,
minlength: 6,
maxlength: 6
},
user:{
type: Schema.Types.ObjectId,
ref: 'User'
}
});
const Otp = mongoose.model('Otp',otpSchema);
// Joi Schema For Otp
function validateOtp(otp) {
const schema = Joi.object({
otpNumber: Joi.string().max(6).required(),
userId: Joi.objectId(), // to validate objectId we used 'joi-objectid' npm package
motive: Joi.string().required(),
isUsed: Joi.boolean().required(),
expiresAt: Joi.Date().required()
});
// async validate function for otp
return schema.validateAsync(otp);
}
exports.Otp = Otp;
exports.validateOtp = validateOtp;

Answer 3

List item
var personSchema = mongoose.Schema({
firstname: String,
lastname: String,
email: String,
gender: {
type: String,
enum: ["Male", "Female"]
}
dob: Date,
city: String,
interests: [interestsSchema],
eventsAttended[{
type: mongoose.Schema.Types.ObjectId,
required: true,
ref: "Place"
}],
**//ref:"Places"...you have put the other model name**
*OR*
eventsAttended[{
type: mongoose.Types.ObjectId,
required: true,
ref: "Place"
}],
});