Mongoose getting the error: MissingSchemaError: Schema hasn't been registered for model

Question

I am getting this error and can't figure it out. I HAVE NAMED THE REF EXACLTY AS THE MODEL: MissingSchemaError: Schema hasn't been registered for model "ParticipantStatus". Here are my models:

ParticipantStatus model:

const mongoose = require('mongoose');
const Schema = mongoose.Schema;

const participantStatusSchema = new Schema({
  _id: {
    type: Number,
    required: true,
  },
  name: {
    type: String,
    required: true,
  },
});

module.exports = mongoose.model('ParticipantStatus', participantStatusSchema);

EventParticipant model:

const mongoose = require('mongoose');
const Schema = mongoose.Schema;

const eventParticipantSchema = new Schema(
  {
    userId: {
      type: Schema.Types.ObjectId,
      ref: 'User',
      required: true,
    },
    eventId: {
      type: Schema.Types.ObjectId,
      ref: 'Event',
      required: true,
    },
    teamId: {
      type: Schema.Types.ObjectId,
      ref: 'Team',
    },
    statusId: {
      type: Number,
      ref: 'ParticipantStatus',
      required: true,
    },
    isActive: {
      type: Boolean,
      required: true,
      default: true,
    },
  },
  { timestamps: true }
);

module.exports = mongoose.model('EventParticipant', eventParticipantSchema);

This is the code where the error is thrown, when i try to get event participants and populate statusId(ParticipantStatus):

 let participants = await EventParticipant.find(
  {
    eventId: req.params.eventId,
    isActive: true,
  },
  { _id: false }
)
  .populate('userId', 'email')
  .populate('statusId')
  .select('userId');

I have been stuck for hours on this. Only the .populate('statusId') part throws the error, the rest works well. Thanks in advance

Answer 1

type of field that you want to populate based on should be ObjectId so change the type of statusId from Number to Schema.Types.ObjectId like this:

statusId: {
    type: Schema.Types.ObjectId,
    ref: 'ParticipantStatus',
    required: true,
  }

Answer 2

Well the problem was that u need to import:

const ParticipantStatus = require('../models/participantStatus.model');

even if you do not REFERENCE IT DIRECTLY in your code, which is really strange in my opinion. Hope this helps anyone.