无法读取未定义的节点js multer的属性'path'

Question

我正在构建一个允许用户创建营地并对其进行编辑的应用程序。最近我添加了上传图片功能，该功能可与创建路线配合使用，但在编辑路线上，它不允许用户将其留空碰巧会出现不确定的错误。您对我的解决方法有任何想法。我经验不足，因此欢迎您提供任何帮助。

这是js代码

var express = require("express");
var router = express.Router({mergeParams:true});
var Campground = require("../models/campground");
var middleware=require("../middleware");
const multer = require('multer');


const storage = multer.diskStorage({
    destination: function(req, file, cb) {
        cb(null, './uploads/');
    },
    filename: function(req, file, cb) {
        const now = new Date().toISOString(); const date = now.replace(/:/g, '-'); cb(null, date + file.originalname);
    }
});

  const fileFilter = (req, file, cb) => {
    // reject a file
    if (file.mimetype === 'image/jpeg' || file.mimetype === 'image/png') {
      cb(null, true);
    } else {
      cb(null, false);
    }
  };

  const upload = multer({
    storage: storage,
    limits: {
      fileSize: 1024 * 1024 * 5
    },
    fileFilter: fileFilter
  });
//edit
router.get("/:id/edit",middleware.checkCampgroundOwnership, function(req,res){


            Campground.findById(req.params.id,function(err,foundCampground){



                      res.render("campgrounds/edit",{campground :foundCampground});


              });



});

router.put("/:id",upload.single('image'),middleware.checkCampgroundOwnership, function(req,res){
    var name = req.body.name;
    var image = req.file.path;
    var description = req.body.description;
    var price = req.body.price

    var upCampground = {price:price,name:name, image: image ,description:description};
    Campground.findByIdAndUpdate(req.params.id,upCampground,function(err,updatedCamp){
        if(err){
            res.redirect("/campgrounds");
        }
        else{
            res.redirect("/campgrounds/"+req.params.id);
        }
    })
}); 

这是ejs之一

<%-include ('../partials/header') %>
<div class="container">

    <h1 style="text-align: center;"> Edit a <%= campground.name%></h1>
    <div style="width: 30%; margin: 25px auto;">
        <form action="/campgrounds/<%=campground._id%>?_method=PUT" enctype="multipart/form-data" method="POST">
            <div class="form-group">
            <input class="form-control" type="text" name="name" value="<%= campground.name%>">
            </div>
            <div class="form-group">
                <input class="form-control" type="number" name="price" value="<%= campground.price%> min="0.01" step="0.01"">
                </div>
            <div class="form-group">
            <input class="form-control" type="file" name="image" value="\<%= campground.image%>">
            </div>
            <div class="form-group">
                <input class="form-control" type="text" name="description" value="<%= campground.description %>">
            </div>
            <div class="form-group">
            <button class="btn btn-primary btn-large btn-block">Submit</button>
        </div>
        </form>
        <a href="/campgrounds">Go back</a>
        </div>



</div>
<%-include ('../partials/footer') %>