multer文件上传不工作

Question

routes.js

module.exports=function(app, upload){

        var postingsController=require('../controllers/postings.server.controller');

        app.post('/postings', postingsController.savePosting);

    }

controller.js

var multer=require('multer');

    exports.savePosting=function(req, res, next){

      // this diskstorage function is not at all executed
        var storage = multer.diskStorage({
            destination: function (req, file, cb) {
                cb(null, './uploads')
            },
            filename: function (req, file, cb) {
                console.log(file);
                cb(null, file.filename + '.' + 'jpg');
            }
        });

        var upload = multer({ storage: storage });
        upload.single('attachment');

        res.json({ message: "success" });

    }

谁能告诉我到底哪一行上传文件。我是在主快件配置文件中写入multer磁盘存储配置，还是可以在任何地方写入。顺便说一下，我可以看到json的响应，这是从行

Answer 1

通常，中间件是在任何实际路由处理程序之外创建和插入的。例如：

routes.js

var multer = require('multer');

var storage = multer.diskStorage({
  destination: function (req, file, cb) {
    cb(null, './uploads')
  },
  filename: function (req, file, cb) {
    console.log(file);
    cb(null, file.filename + '.' + 'jpg');
  }
});
var upload = multer({ storage: storage });

module.exports = function(app, upload) {
  var postingsController = require('../controllers/postings.server.controller');

  app.post('/postings',
           upload.single('attachment'),
           postingsController.savePosting);
};

controller.js

exports.savePosting = function(req, res, next) {

  // Use `req.file` to access attachment

  if (req.file)
    res.json({ message: "success" });
  else // no file uploaded
    res.json({ message: "failure" });
};

Answer 2

Multer是一种中间件，这意味着在大多数情况下，它是作为参数添加到您的路由中的。因此，实际语法是这样的：

app.post ("/postings", multer ({ ... }), postingsController.savePosting);

在对"/postings“的请求和为您完成所有文件工作的最后一个函数之间调用Multer。然后它将向您提供所有的信息

req.files["fileInputName"]

在下面的中间件中(您的函数也是一个“中间件”)。