An example for reversing population in Mongoose

controller.js

// Gets a list of Types
export function index(req, res) {

  Type.find({})
    .populate('products')
    .exec((err, types) => {
      if (err) handleErr(err, res);
      async.forEach(types, function (type, done) {
        Product.find({type: type._id}, '-type -market')
          .exec(function (err, products) {
            type.products = products;
            done(err);
          });
      }, function (err) {
        handleResult(types, res);
      });
    });
}

function handleErr(err, res, statusCode) {
  statusCode = statusCode || 500;
  return res.status(statusCode).send(err);
}

function handleResult(entity, res, statusCode) {
  statusCode = statusCode || 200;
  return res.status(statusCode).json(entity);
}

model.js

// Suppose that we have Type and Product model with one-to-many relationship.

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

var TypeSchema = new mongoose.Schema({
  id: Schema.Types.ObjectId,
  name: String,
  products: [{
    type: Schema.Types.ObjectId,
    ref: 'Product'
  }]
}, {versionKey: false});

var ProductSchema = new mongoose.Schema({
  id: String,
  name: String,
  unit: String,
  price: Number,
  imageUrl: String,
  type: {
    type: Schema.Types.ObjectId,
    ref: 'Type'
  },
  order: {
    type: Schema.Types.ObjectId,
    ref: 'Order'
  },
  market: {
    type: Schema.Types.ObjectId,
    ref: 'Market'
  }
}, { versionKey: false });