node.js - 正则表达式搜索错误

Question

我对 mongo Node 和 Express 有点陌生，我遇到了一些问题。我正在尝试根据某些关键字查询数据库中的所有产品。理想情况下，我想找到一个包含用户搜索中的单词的产品，如果没有发现任何单词包含在集合中，则默认为固定产品

这是我的架构设置:

var  express  = require("express"),
    mongoose = require("mongoose");

var productSchema  = new mongoose.Schema({
    name:  String,
    image: String,
    description:  String,
    keywords:  String,
});

module.exports = mongoose.model('产品', ProductSchema);

我的想法是根据用户的查询将用户与产品相匹配。即使他们输入完整的句子(目前仅适用于单个单词)。如果没有产品，我想默认为数据库中的一种产品。这是我的路线设置:

var express  = require("express"),
    Product  =require('../models/product'),
    router   = express.Router();

router.get('/myroute', function(req,res){
// if there's a query
    if(req.query.search){
    const regex = new RegExp(escapeRegex(req.query.search), 'gi'); 
    var regexSearch = {
        "keywords": {
                "$regex": regex
          }
    };
    Product.findOne(regexSearch, function(err, foundProduct){
        if(err){
            console.log('product not found');
        } else{
            res.render('show', {product: foundProduct});
              }
    });

    } else{
          Product.findOne({name: 'defaultP'}, function(err, foundProduct){        
              if(err){
                  console.log(err);
              } else{
                  res.render('show', {product: foundProduct});
              }
          });

      }  

  });

function escapeRegex(text) {
    return text.replace(/[-[\]{}()*+?.,\\^$|#\s]/g, "\\$&");
};

module.exports = router;

目前，当我搜索存在的关键字(但不是句子)时，一切正常。但是，如果我搜索数据库中不存在的句子或关键字，则会在渲染时收到错误:

Cannot read property 'name' of null at eval (eval at (/home/ubuntu/workspace/node_modules/ejs/lib/ejs.js:524:12), :22:33) at returnedFn (/home/ubuntu/workspace/node_modules/ejs/lib/ejs.js:555:17) at tryHandleCache (/home/ubuntu/workspace/node_modules/ejs/lib/ejs.js:203:34) at View.exports.renderFile [as engine] (/home/ubuntu/workspace/node_modules/ejs/lib/ejs.js:412:10) at View.render (/home/ubuntu/workspace/node_modules/express/lib/view.js:128:8) at tryRender (/home/ubuntu/workspace/node_modules/express/lib/application.js:640:10) at EventEmitter.render (/home/ubuntu/workspace/node_modules/express/lib/application.js:592:3) at ServerResponse.render (/home/ubuntu/workspace/node_modules/express/lib/response.js:971:7) at /home/ubuntu/workspace/routes/match.js:20:23 at Query. (/home/ubuntu/workspace/node_modules/mongoose/lib/model.js:3755:16) at /home/ubuntu/workspace/node_modules/mongoose/node_modules/kareem/index.js:277:21 at /home/ubuntu/workspace/node_modules/mongoose/node_modules/kareem/index.js:131:16 at nextTickCallbackWith0Args (node.js:436:9) at process._tickCallback (node.js:365:13)

Answer 1

尝试一下，然后将函数 escapeRegex 放入 RegExp 中。

var regExpr = new RegExp(".*" + req.query.search + ".*", "i");
var regexSearch = {
    "keywords": regExpr
};