Which is the better approach to upload images via nginx? - node.js

Question

I want to implement file uploading via nginx and FileAPI on client side. So I have the following questions:
Which is module better suite for this task nginx-upload-module or native clientbodyinfileonly or something else?
How to check that user is authenticated before uploading starts (maybe touch backend and return some data back to nginx like user_id)
How to rename file to hash to be looks like the following www.mysite.com/files/011/b0f/639/011b0f639f69491e9e4cbaf41656297f.jpg ?
How to make and save three copy of uploaded image several sizes (128x128, 96x96, 30x30)?

Answer 1

Which is module better suite for this task nginx-upload-module or
native clientbodyinfileonly or something else?
I just had a look at nginx-upload-module and this is a 7 years old nginx module to handle multipart requests. Nginx has been supporting multipart uploads for years now, so you do not need to change anything to your nginx setup as long as you're not running a 7 years old version!
For the remaining questions I'll give you an example, using :
Thumbnail to generate the thumbnails (You will need graphitemagick installed, but you can replace it with any other lib)
Q to easily generate the different thumbnails concurrently and have a clean code with no callback pyramid
Multer to handle the file upload server-side.
You could use other libraries to do the same thing, but this will show you one way to do it easily. For the sake of this example it is all in one single file.
var express = require('express');
var multer = require('multer');
var md5 = require('MD5');
var Q = require('q');
var Thumbnail = require('thumbnail');
var app = express();
var targetFolder = '/var/www/mysite/files/full/';
var thumbnailFolder = '/var/www/mysite/files/thumbs/';
var thumbnail = new Thumbnail(targetFolder, thumbnailFolder);
var makeThumbnail = Q.nbind(thumbnail.ensureThumbnail,thumbnail);
var thumbnailSizes = [30,96,128];
app.post('/upload', function(req,res,next) {
//Check the authentication here, this is the first middleware.
if(authenticated) {
next();
} else {
res.send(401);
}
}, multer({
dest: targetFolder,
rename: function (fieldname, filename) {
//Rename the file with it's name + date hash
return md5(filename + Date.now());
},
onFileUploadComplete: function(file, req, res) {
var resizePromises = [];
for(var i in thumbnailSizes) {
var p = makeThumbnail(file.name,thumbnailSizes[i],thumbnailSizes[i]);
resizePromises.push(p);
}
Q.all(resizePromises).done(function(){
// The file has been resized to the specified format.
res.send(200);
},function(err) {
console.log(err);
res.send(500);
// Error !
});
}
});