associating orders to products - node.js

Question

I have an issue trying to associate a particular order with a particular product. I am new to node.js, I want to add a product(be associated and be populated with an order) and be redirected to a page which shows all orders of products i created
created the product and order schema(not too sure about the other schema)...
This is my product model
var mongoose= require("mongoose");
var productSchema = new mongoose.Schema({
name:String,
brand:String,
price: Number,
image: String,
description:String,
featured: Boolean,
});
module.exports= mongoose.model("Product", productSchema);
This Is order model:
var mongoose = require("mongoose");
var orderSchema= new mongoose.Schema({
_id: mongoose.Schema.Types.ObjectId,
products:[
{
type: mongoose.Schema.Types.ObjectId,
ref:"Product", required:true
}
]
,
quantity :{type:Number, default:1}
});
module.exports=mongoose.model("Order",orderSchema);
I want this models to be associated together using the mongoose method, be populated and then appear on a route ("/order) for example. I am new to programming and as such the simplest answer would be appreciated.

Answer 1

Here is a small working example using Express.Js, in this example I created 3 models :
// Models
const productSchema = new mongoose.Schema({
name:String
});
var orderSchema= new mongoose.Schema({
products:[productSchema]
});
const clientSchema = new mongoose.Schema({
name: String,
order: {
type: mongoose.Schema.Types.ObjectId,
ref: 'Order'
}
})
const Product = mongoose.model('Product', productSchema);
const Client = mongoose.model('Client', clientSchema);
const Order = mongoose.model('Order', orderSchema);
My orderSchema will embed the products ordered by my clients, I chose to store products as subdocuments because I will have only few, you could also choose to store references instead.
Note: I'a referencing only one order per Client, you could choose otherwise, and make the order field in the clientSchema in an array (order: [{ /* type...*/}])
In my controller I have 2 methods: one to create an order and the other to add a product to the order.
// Controller
const createOrder = (userId, productId) => {
Product.findOne({_id: productId}) // find a product
.exec()
.then(product => new Order({products: [product]}).save()) // save the products into the order
.then(order => Client.findOneAndUpdate({_id: userId}, {$set: {order: order}}).exec())// update the client document with the new order
.then(client => res.json(client)); // respond with json
// .catch(err => console.log(err))
}
const addToOrder = (userId, productId) => {
return Product.findOne({_id: productId}) // find the product
.exec()
.then(product => {
return Client.findOne({_id: userId})//find the client
.populate({ path: 'order', populate: { path: 'order.products' } })
.exec() //populate in order to access client.order.products
.then(client => {
client.order.products.push(product);
return client.order.save();
})
})
// .catch(err => console.log(err));
}
I know need two routes: one to render a table with all the available products and one to render a cart with the ordered items.
// Get all products
app.get('/products', function(req, res) {
Product.find({})
.exec()
.then(products => res.render('products.ejs', {allProducts: products}))
.catch(err => res.json({errors: err}));
});
// Order a product
app.get('/products/:productId/order', function(req, res) {
req.user = {id: ""} /* id of the client, or the logged in user if you're using passeport or some other auth manager */
Client.findOne({_id: req.user.id})
.exec()
.then(client => {
if(client.order) {
return addToOrder(client.id, req.params.productId)
.then(order => res.render('cart.ejs', {order: order}))// render cart with the order
} else {
return createOrder(client.id, req.params.productId)
.then(order => res.json('cart.ejs', {order: order}))
}
})
.catch(err => res.json({errors: err}));
})
I need two (rendered by my route handlers):
// /views/products.ejs
<div>
<table>
<% allProducts.forEach(function(product) { %>
<tr>
<th>name</th>
</tr>
<tr>
<td><%= product.name %></td>
<td><a href=<%=`/products/${product.id}/order`%>> Order </a> </td>
<tr>
<% }) %>
</table>
</div>
// views/cart.ejs
<div>
<table>
<% order.products.forEach(function(product) { %>
<tr>
<th>name</th>
</tr>
<tr>
<td><%= product.name %></td>
<tr>
<% }) %>
</table>
</div>
I hope this helps.