Mongoose: reference between models with same schema keys

Question

As a front-end developer, I would like to have some isomorphic object for two mongoose models.

Let's say I have a user profile:

const profileSchema = new Schema({
  firstName: { type: String },
  lastName: { type: String },

  // example of difference between model schemas
  __user: { type: ObjectId, ref: 'Users' },
}

And I would like to create a list of Contact, where each contact will have some of the same keys:

const contactSchema = new Schema({
  firstName: { type: String },
  lastName: { type: String },

  __profile: {
    type: ObjectId,
    ref: 'Profiles',
    unique: true,
  },

  comment: { type: String }, 
}

NOTE: Contact could be the both:

• as a reference to the Profile
• and as independent record in DB / document.

==============================

My question: which is the best way to, organize models on such a way, so

• contact could be a reference to the profile
• when similar Profile key, like firstName will be updated, contact firstName will be updated too

AVOID of next ref

await Contact.findById(SOME_ID).populate('__profile');

// result
{
  firstName: '',
  lastName: '',

  __profile: {
    firstName: 'Chuck',
    lastName: 'Norris',
  }
}

Desired result - keep contact "isomorphic" like:

{
  firstName: 'Chuck', // the key value from profile
  lastName: 'Norris', // the key value from profile

  __profile: SOME_PROFILE_ID,
}

Is this possible?

P.S: in my app, I'm using refs and started to use discriminators approaches.

Answer 1

In my case, complete usage of Mongoose discriminators did not give me an advantage, because discriminators give you an opportunity to:

They enable you to have multiple models with overlapping schemas on top of the same underlying MongoDB collection.

As a result, by using discriminators approach, I will reive one collection of:

• profiles

And there will be a mix of users and contact profiles.

==============================

So I decided to use two approaches:

• create BesaSchema for the profile
• take advantage of Mongoose Subdocuments

RESULT:

// keys which are same for both user Profile and Contact
const Schema = require('mongoose').Schema;
const util = require('util');

function BaseProfileSchema(...args) {
  Schema.apply(this, args);

  this.add({
    firstName: { type: String },
    lastName: { type: String },
  });
}
util.inherits(BaseProfileSchema, Schema);

// user Profile Model
const profileSchema = new BaseProfileSchema({
  __user: {
    type: String,
    ref: 'users',
    required: true,
    unique: true,
  },
});

const Profile = mongoose.model('profiles', profileSchema);

// Contact with profile as subdocument
const contactProfileSchema = new BaseProfileSchema();

const contactSchema = new Schema({
  // Associations
  __refProfile: {
    type: Schema.Types.ObjectId,
    ref: 'profiles',
    index: {
      unique: true,
      sparse: true,
    },
  },
  profile: contactProfileSchema,
});

const Contact = mongoose.model('contacts', contactSchema);

As a result, I'm having DB with next collections:

• users
• profiles
• contacts

Both profiles and contacts.profile are IDENTICAL because I'm extending the base shared schema.

Moreover:

• inside Contact I'm having different keys for real referenced profile (__refProfile which can NOT be edit by others) and contact.profile
• profile inside connection can be edited ONLY when the contact was edited by itself

P.S: happy codding 👨‍💻🍻