获取我的收藏，req.query (express,node.js)

Question

I want to recover my collection which is in the database. The problem is that my query is still not defined.

Here is my request:

const products = {
  getProducts: async (req, res) => {
    const productId = req.query.id;
    console.log(productId);
    const product = await ProductsModel.find({}).exec();

    if (product instanceof Error) {
      res.status(500).json({ message: "Error" });
      return;
    }

    res.json(product);
  },
};
module.exports = products;

My schema with mongoose :

const ProductSchema = new mongoose.Schema({
  image: {
    type: String,
  },
  title: {
    type: String,
  },
  description: {
    type: String,
  },
  price: {
    type: Number,
  },
  category: {
    type: String,
  },
});

const Products = mongoose.model("Products", ProductSchema);

module.exports = Products;

My Fetch :

const [products, setProducts] = useState([]);
useEffect(getProducts, []);

async function getProducts() {
    const options = {
      method: "GET",
    }

    const response = await fetch("http://localhost:8000/products", options);
    const productsData = await response.json();

    setProducts(productsData);
    console.log(productsData);
  }

My error message :

[nodemon] restarting due to changes...

[nodemon] starting node ./bin/www

(node:4279) DeprecationWarning: collection.ensureIndex is deprecated. Use createIndexes instead.

(Use node --trace-deprecation ... to show where the warning was created)

undefined

GET /products 304 14.493 ms - -

Thank you in advance for your help.

Answer 1

At first, while exporting from your Schema file you have done:

module.exports = Products;

But on your Request file while fetching product you have done:

const product = await ProductsModel.find({}).exec();

You should replaced it with:

const product = await Products.find({}).exec();

You are getting undefined on req.query because while request on server you have not passed query. To pass query use ?id= In your Fetch File you should do following change:

const response = await fetch("http://localhost:8000/products?id="+productId, options);

Or, You can also use Tempelate Literals `` , this is a good practice.

const response = await fetch(`http://localhost:8000/products?id=${productId}`, options);

For deprecation warning, you have to do following changes where you have connect databse.

  mongoose.connect('mongodb://localhost:27017/name',{
  useNewUrlParser: true,
  useUnifiedTopology: true,
  useCreateIndex:true},()=>{console.log('database connected')}