nodejs发送文件到public内，调用oss接口上传文件。

  
<input type="file" name="" id="photo">
$("#photo").on("change", function () {
        let file = $(this)[0].files[0];
        let formdata = new FormData();
        formdata.append("photo", file);
        $.ajax({
            type: 'post',
            url: '/api/pro/picture',
            data: formdata,
            contentType: false,
            processData: false,
            success: function (data) {

            }
        })
    })

const express = require("express");
const router = express.Router();
const fs = require("fs");
const multer = require('multer');
const upload = multer()
const stringRandom = require('string-random');
let OSS = require('ali-oss');
let client = new OSS({
  // 仓库地域节点
  region: 'oss-cn-shanghai',
  //云账号AccessKey有所有API访问权限，建议遵循阿里云安全最佳实践，部署在服务端使用RAM子账号或STS，部署在客户端使用STS。
  // oss 中 密钥id
  accessKeyId: '***',
  // oss 访问权限代码
  accessKeySecret: '***',
  //  存储仓库名字
  bucket: '***',
  secure:true  // https
  cname: true,  
  endpoint: "xxx.com"  支持自定义域名 必须和cname一起使用
});

router.post(`/picture`, upload.single('photo'), (req, res) => {
  // 获取名字
  let file_name = req.file.originalname
  // 获取后缀名
  file_name = file_name.replace(/.+\./, "");
  // 生成随机名字
  let randomName = stringRandom(16);
  // 拼接文件名字
  let fileName = randomName + "." + file_name;
  // 创建写入流
  let ws = fs.createWriteStream('./public/upload/' + fileName);
  // 写入buffer数据
  ws.write(req.file.buffer);
  // 文件写入结束
  ws.end(async function () {
                                 //     oss仓库地址          要上传文件的地址
    let result = await client.put('/images/' + fileName, './public/upload/' + fileName);
    if (result.res.status != 200) {
      res.json({
        code: "400",
        msg: "上传失败"
      })
    } else {
      res.json({
        data: { pic: result.url },
        code: 200,
        msg: "上传成功"
      })
    }
  })
})

<el-upload
    class="upload-demo"
    action=""
    multiple
    :http-request="upLoadFile"
  >
    <el-button size="small" type="primary">点击上传</el-button>
  </el-upload>


 upLoadFile(param){
            let fileObject = param.file;
            let formData = new FormData();
            formData.append("photo", fileObject);
            upload(formData)
            .then(res=>{
             console.log(res);
            })
            .catch(err=>{
             console.log(err);
            })
        }