nodejs image upload function

const express = require('express');
const router = express.Router();
const multer = require('multer');

var storage = multer.diskStorage({
    
    
    // 设置上传后文件路径，uploads文件夹会自动创建
    destination: function(req, file, cb) {
    
    
        cb(null, './uploads')
    },
    //给上传文件重命名，获取添加后缀名
    filename: function(req, file, cb) {
    
    
        console.log(req)
        var exts = (file.originalname).split('.');
        var ext = exts[exts.length - 1];
        let tempname = (new Date).getTime() + parseInt(Math.random() * 9999);

        // 给图片加上时间戳格式防止重命名
        //比如把 abc.jpg图片切割为数组[ABC.JPG],然后用数组长度-1获取后缀名
        cb(null, `${
      
      tempname}.${
      
      ext}`);

    }
});

var upload = multer({
    
    
    storage: storage
})

router.post('/upload', upload.single('img'), (req, res) => {
    
    
    console.log(res.file)
    let {
    
     size, mimetype, path } = req.file;
    console.log(path, "路径")
    let types = ['jpg', 'jpeg', 'png', 'gif'];
    let tmpType = mimetype.split('/')[1];

    if (size > 500000) {
    
    
        return res.send({
    
    
            err: -1,
            msg: "尺寸过大"
        })
    } else if (types.indexOf(tmpType) == -1) {
    
    
        return res.send({
    
    
            err: -1,
            msg: "媒体类型错误"
        })

    }
    res.send({
    
    
        msg: 0,
        data: "上传OK",
        img: path
    })
})
module.exports = router;