Route for getting a review for a book in a MERN-stack book review app?

JavaScript
1

I am trying to write a MERN stack app used for reviewing books.

I have 2 MongoDB (Mongoose) schemas: models/Book.js and models/Review.js, where one Book can have multiple Reviews.

These are my schemas:

models/Review.js:

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

let reviewSchema = new Schema(
    {
        text: {
            type: String
        },
        book: {
            type: mongoose.Schema.Types.ObjectId,
            ref: 'Book'
        }
    }
);

module.exports = mongoose.model('Review', reviewSchema)

models/Book.js:

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

let bookSchema = new Schema(
    {
        title: {
            type: String
        },
        detail: {
            type: String
        }
    }, {
        collection: 'books'
    }
);

module.exports = mongoose.model('Book', bookSchema)

How should a route look like if I want to get all data about a single book via this URL: /book/<book_id_from_mongodb>?

I can only get Book’s data but I don’t know how to get all Reviews that belong to that particular book:

/routes/book.route.js:

let mongoose = require('mongoose'),
    express = require('express'),
    router = express.Router();

let bookSchema = require('../models/Book');
let reviewSchema = require('../models/Review');

// Get a single book - HOW SHOULD I MODIFY THIS ROUTE TO GET ALSO ALL REVIEWS FOR THAT BOOK ?
router.route('/book/:id').get((req, res) => {
    bookSchema.findById(req.params.id, (error, data) => {
        if (error) {
            res.status(500).send(err);
        } else {
            res.status(200).json(data)
        }
    })
})