File upload using NodeJs in Rails app

I have a rails application for uploading file things that is working fine but to improve the performance i decided to go with Node Js

If i clicked on submit it is going throw normal way ,,it should go bu node js

View File

<%= form_tag({:controller => "question_bank", :action => "upload_question_bank"}, {:class => "schedule_form", :id => "schedule_form", :enctype => "multipart/form-data"}) do  %>
<div class="group_fixed">
    <%= label_tag :Syllabus %>
    <span>:</span>
    <%= file_field_tag "qbank_import", {:class => 'textBoxWidth'} %>
</div>

<div class="actions">
    <%= submit_tag "Upload Syllabus", {:class=>'submit_button', :id => "submit_qbank"}%>
 </div>
</div>

<%end%>

Routes.rb

resources :question_bank do
    post "upload_question_bank", :on => :collection    
end

Controller.rb

def upload_question_bank
file_format = `file -ib "#{params[:qbank_import].path}"`.gsub(/\n/,"").split("\;")[0]
if file_format == "application/pdf"
  asset = DigitalAsset.save_asset(@site, params[:qbank_import].dup,request.remote_ip)
  asset.update_attributes(params[:digital_asset])
  asset.asset_type="question-bank"
  asset.uploaded_for = params[:uploaded_for]
  asset.academic_session_id = @academic_session.id
  asset.remote_ip = request.remote_ip
  asset.save
end
redirect_to "/syllabus"
end

Running Node Js ## node Server.js That is working fine

Link that i`m following file-uploads-using-node-js

Server.js

var express = require("express");
var multer  = require('multer');
var app = express();
var done = false;

/*Configure the multer.*/

app.use(multer({ dest: './uploads',
 rename: function (fieldname, filename) {
    return filename+Date.now();
  },
onFileUploadStart: function (file) {
  console.log(file.originalname + ' is starting ...')
},
onFileUploadComplete: function (file) {
  console.log(file.fieldname + ' uploaded to  ' + file.path)
  done=true;
}
}));

/*Handling routes.*/

//app.get('/',function(req,res){
//      res.sendfile("index.html");
//});

app.post('/question_bank/upload_question_bank',function(req,res){
  if(done==true){
    console.log(req.files);
    res.end("File uploaded.");
  }
});

/*Run the server.*/
app.listen(3000,function(){
    console.log("Working on port 3000");
});

package.json

 {
  "name": "file_upload",
  "version": "0.0.1",
  "dependencies": {
    "express": "^4.10.8",
    "multer": "~0.1.6"
  }
}

Any help would be greatly appreciate. Do comment if any one need any extra information.