title: Do I need Rack middleware for having a file upload with progress via HTML5 (File API + XMLHttpRequest Level 2)
body: <p>I'd like to build a (multi) file upload with progress indicator for a Rails app. Moreover I do not want to use a Flash based solution. </p>
  
  <p>I've found a number of jQuery libraries (e.g. <a href="https://github.com/blueimp/jQuery-File-Upload" rel="nofollow">https://github.com/blueimp/jQuery-File-Upload</a>) that implement the File API and XMLHttpRequest Level 2 API to have Ajax file uploads. </p>
  
  <p>What I am wondering about is whether I need some extra Rack middleware, as appears to be claimed at the end of this article: <a href="http://blog.new-bamboo.co.uk/2010/7/30/html5-powered-ajax-file-uploads" rel="nofollow">http://blog.new-bamboo.co.uk/2010/7/30/html5-powered-ajax-file-uploads</a></p>
  
  <p>I've already tried the single file ajax file up load using the blueimp library and all appears to go well, without any Rack middleware. So my question is, why is that? And in which scenario do I need the middleware?</p>
  
  <p>Thnx!</p>