产品过滤节点js+sequelize

Question

我正在使用节点 js + sequelize。我想按供应商、价格、交货选项等选择的选项过滤产品的结果，但我不明白如何使查询准确。

现在我正在这样做，但此方法仅在选择所有过滤器时才有效（AND 运算符）。如果用户只选择了 1 个过滤器，或者其中几个过滤器，我该怎么办？

    let vendor = req.query.vendor;
    let priceFrom = req.query.priceFrom;
    let priceTo = req.query.priceTo;
    let delivery = req.query.delivery

            Product.findAll({
                where: {
                    vendor_id: {
                        in: vendor
                    },
                    price: {
                        $between: [priceFrom, priceTo]
                    },
                    {
                    delivery: delivery 
                    }
                }
            }).then(products => {
                res.render('product', {products: products});
                console.log(products)
            });

我现在看到唯一的一种方法可以为每个场合编写大量 if-else 语句。

Answer 1

首先，检查查询参数并根据这些查询参数创建一个对象，例如：

let vendor = req.query.vendor;
let priceFrom = req.query.priceFrom;
let priceTo = req.query.priceTo;
let delivery = req.query.delivery
let options = { where: {} };
if (vendor)
    options.where.vendor_id = {$in: vendor}
if (priceFrom && priceTo)
    options.where.price = {$between: [priceFrom, priceTo]}
if (delivery)
    options.where.delivery = delivery
Product.findAll(options)
  .then(products => {
      console.log(products)
      res.render('product', { products: products });
  });

Answer 2

您也可以使用odata-sequelize 之类的包。它简化了过滤过程。

var parseOData = require("odata-sequelize");
var sequelize = require("sequelize");
var query = parseOData(
  "$top=5&$skip=1&$select=Foo,Bar&$filter=Foo eq 'Test' or Bar eq 'Test'&$orderby=Foo desc",
  sequelize
);

这会产生

{
    attributes: ['Foo', 'Bar'],
    limit: 5,
    offset: 1,
    order: [
        ['Foo', 'DESC']
    ],
    where: {
        [Op.or]: [
            {
                Foo: {
                    [Op.eq]: "Test"
                }
            },
            {
                Bar: {
                    [Op.eq]: "Test"
                }
            }
        ]
    }
}