Node.js TypeError: Unable to read properties file 'w90>

Question

I am just learning node.js and can hardly make simple file uploads using express and multer .

Here is the form:

Upload image

In my configure.js , I have:

 app.use(express.static(path.join(__dirname, 'public'))); app.use(multer({dest:'../public/upload/temp'}).single('file')); 

And the image.js controller:

 create: function(req, res) { var saveImage = function() { console.log(req.body); var possible = 'abcdefghijklmnopqrstuvwxyz0123456789', imgUrl = ''; for(var i=0; i < 6; i+=1) { imgUrl += possible.charAt(Math.floor(Math.random() * possible.length)); } var tempPath = req.files.file.path, //<line 55 error ext = path.extname(req.files.file.name).toLowerCase(), targetPath = path.resolve('./public/upload/' + imgUrl + ext); if (ext === '.png' || ext === '.jpg' || ext === '.jpeg' || ext === '.gif') { fs.rename(tempPath, targetPath, function(err) { if (err) throw err; res.redirect('/images/' + imgUrl); }); } else { fs.unlink(tempPath, function () { if (err) throw err; res.json(500, {error: 'Only image files are allowed.'}); }); } }; saveImage(); }, 

However, I get this error when trying to upload an image:

 TypeError: Cannot read property 'file' of undefined at saveImage (/home/pc/node-dev/test-proj/controllers/image.js:55:37) at module.exports.create (/home/pc/node-dev/test-proj/controllers/image.js:76:9) at Layer.handle [as handle_request] (/home/pc/node-dev/test-proj/node_modules/express/lib/router/layer.js:95:5) at next (/home/pc/node-dev/test-proj/node_modules/express/lib/router/route.js:131:13) at Route.dispatch (/home/pc/node-dev/test-proj/node_modules/express/lib/router/route.js:112:3) at Layer.handle [as handle_request] (/home/pc/node-dev/test-proj/node_modules/express/lib/router/layer.js:95:5) at /home/pc/node-dev/test-proj/node_modules/express/lib/router/index.js:277:22 at Function.process_params (/home/pc/node-dev/test-proj/node_modules/express/lib/router/index.js:330:12) at next (/home/pc/node-dev/test-proj/node_modules/express/lib/router/index.js:271:10) at urlencodedParser (/home/pc/node-dev/test-proj/node_modules/body-parser/lib/types/urlencoded.js:95:37) 

And when I register the req object, file does not exist:

 { title: 'myimage', description: 'something' } 

In fact, the snippet is just a slightly modified version that I read in this book that uses the deprecated express-3. So I just updated it using the multer part.

I wonder what is wrong here and how to fix it.

Answer 1

You are using upload.single , which you should use req.file not req.files . To upload multiple files, use upload.array .

Please note that after req.file you do not need another .file . req.file is the downloaded file if you use upload.single .