猫鼬试图填充

Question

我有一些问题

1. 无法填充 CartProduct，只显示 ObjectId。
2. 有没有办法让 CartProduct 每次创建时自动添加到？购物车。
3. 这是正确的模式结构方式吗？

购物车

 const CartSchema = new Schema({
  active: { type: Boolean, required: true, default: true },
  createAt: { type: Date, default: Date.now },
  client: { type: Schema.Types.ObjectId, ref: "User", required: true },
 products: [{ type: Schema.Types.ObjectId, ref: "CartProduct" }],
 });

 const Cart = model("Cart", CartSchema);

购物车产品

const CartProductSchema = new Schema({
item: { type: Schema.Types.ObjectId, ref: "Product", required: true },
cart: { type: Schema.Types.ObjectId, ref: "Cart", required: true },
quantity: { type: Number, required: true },
totalPrice: { type: Number, required: true },
});

const CartProduct = model("CartProduct", CartProductSchema);

产品

 const ProductSchema = new Schema({
 name: { type: String, required: true },
 price: { type: Number, required: true },
 image: { type: String, required: true },
 category: { type: Schema.Types.ObjectId, ref: "Category", require: true },
  });

 const Product = model("Product", ProductSchema);

购物车控制器

router.post("/", async (req, res) => {
 try {
  const { userId } = req.body;
   const cart = await Cart.findOne({ client: userId 
  }).populate("CartProduct");

   if (cart === null) {
     const newCart = new Cart({
       client: userId,
     });

    await newCart.save();

   return res.status(201).send({ cart: newCart });
  }

   res.status(200).send({ cart });
 } catch (error) {
   res.status(500).send(error);
   }
  });

将产品添加到购物车

router.post("/addProductToCart", async (req, res) => {
try {
const { item, cart, quantity, price } = req.body;

const newProduct = new CartProduct({
  item,
  cart,
  quantity,
  totalPrice: price * quantity,
});

await newProduct.save();

await Cart.findOneAndUpdate(
  { _id: cart },
  { $push: { products: newProduct } },
  {
    new: true,
  }
);

res.status(201).send({ message: "New Product Added To Cart" });
} catch (error) {
  res.status(500).send(error);
}
});

将产品添加到购物车确实有效， 但填充不起作用

添加输出

{
"cart": {
    "active": true,
    "products": [
        "602bc081daf867167c2eb5da"
    ],
    "_id": "602aab802f625d1654805ef0",
    "client": "601c50211c94cf5d642c67fb",
    "createAt": "2021-02-15T17:12:32.997Z",
    "__v": 0
 }
}

Answer 1

您在 cartSchema 中缺少的 {

 const CartSchema = new Schema({
  active: { type: Boolean, required: true, default: true },
  createAt: { type: Date, default: Date.now },
  client: { type: Schema.Types.ObjectId, ref: "User", required: true },
 products: [{ type: Schema.Types.ObjectId, ref: "CartProduct" }],
 });

像这样导出模型

module.exports = Cart 

有没有办法让 CartProduct 每次创建时自动添加到？购物车

没有自动将CartProduct 中的_id 添加到collection，因此您应该使用findOneAndUpdate() 或find() 和push in to products array 和save()

这是正确的模式结构方式

是的。

所以对于填充你可以尝试：

let resultCarts = await Cart.find(filter).populate("products")
let resultProducts = await Product.find(filter).populate("category")

因此将CartProduct 更改为products，因为您应该将字段名称作为参数而不是架构名称传递

await Cart.findOne({ client: userId 
  }).populate("products");