Multer req.file 未定义 - 使用 Node/Express 将图像上传到 s3

问题描述

我知道这个问题已经被问了很多，我已经尝试了几乎所有的答案来尝试让它运行，但我一直没有为 req.file 定义。

代码如下：

services.imageUpload.js

const aws = require("aws-sdk");
const multer = require("multer");
const multerS3 = require("multer-s3");

aws.config.update({
  secretAccessKey: "XXXXXXXXXXXXX",accessKeyId: "XXXXXXXXXXXX",region: "XXXXXXX",});
const s3 = new aws.S3();

const upload = multer({
  storage: multerS3({
    s3: s3,bucket: "XXXXXXXXX",Metadata: function (req,file,cb) {
      cb(null,{ fieldName: "TESTING_Meta_DATA" });
    },key: function (req,req.s3key);
    },}),});

module.exports = upload;

routes.imageUpload.js

const express = require("express");
const router = express.Router();
const upload = require("../services/imageUpload");

const singleUpload = upload.single("image");

router.post("/",function (req,res) {
  singleUpload(req,res,function (err) {
    return res.json({ request: req.file.location });
  });
});

module.exports = router;

index.js

const express = require("express");
const app = express();
const cors = require("cors");
const imageUpload = require("./routes/imageUpload");

//Middleware
app.use(cors());
app.use(express.json());

//Image upload
app.use("/upload-image",imageUpload);

app.listen(5000,() => {
    console.log("server is running on port 5000");
});

非常感谢您的帮助！很令人沮丧。目前正在使用邮递员测试 API 并发送 POST 请求作为表单数据，键为“图像”和上传图像文件的值。

解决方法

在您的 index.js 中，您可以携带

const upload = require("../services/imageUpload");

在顶部然后在这里初始化multer中间件

//Middleware
app.use(cors());
app.use(express.json());
app.use(upload.single("image"))

然后在 routes.imageUpload.js 中，您可以像这样读取上传的文件

router.post("/",function (req,res) {
    let fileDetails = req.files
    console.log(fileDetails )
    .
    .
    .
});

或者，如果您只需要 routes.imageUpload.js 中的上传器，您可以像这样使用中间件，

const express = require("express");
const router = express.Router();
const upload = require("../services/imageUpload");

const singleUpload = upload.single("image");

router.post("/",[singleUpload],res) {
    let fileDetails = req.files
    console.log(fileDetails )
    .
    .
    .
});