var express = require('express'),
    app     = express(),
    redis   = require('redis'),
    client  = redis.createClient(),
    QRCode  = require('qrcode');
 
app.use(express.bodyParser());
 
app.post('/new', function(req, res){
  if(req.body.url){
    var url_id = new Buffer(req.body.url).toString('base64');
    client.keys(url_id,function(err,keys) {
      if (err) res.send({'message':'Internal Server Error'},500);
      if (keys.length != 0){
        res.send({'message':'Conflict','keys':keys},409);
      }
      else {
        client.set(url_id, req.body.url,function(err,status){
          if (err) res.send({'message':'Internal Server Error'},500);
          else {
           
            QRCode.toDataURL('http://localhost:3000/go/'+url_id,function(err,dataURL){
              var response = {
                    qrcode : dataURL
                  };
                  response[url_id] = req.body.url;
              res.send(response,200)
            });
           
          };
        });
       
      }
    });
   
  }
  else {
    res.send(400)
  }
});
 
app.get('/go/:hash',function(req,res){
  if(req.params.hash){
    client.exists(req.params.hash, function (err, doesExist) {
      if (doesExist == false) {
        res.send({'message':'Not Found'},404);
      };
      if (doesExist == true) {
        client.get(req.params.hash,function(err,url) {
          if (err) res.send({'message':'Internal Server Error'},500);
          else {
            res.redirect(url.toString(), 301);
          }
        })
      }
    });
  }
  else{
    res.send(404)
  }
});
 
app.listen(3000);
console.log('Listening on port 3000');

It currently uses redis as a store for the data. The url's are pretty long since it's all base64 encoded data and the images are returned as base64 encoded PNG's but that can be solved pretty easily. This could be used a service for something kind of authentication front end, drupal

node.js_url_shortener_w_qr_code_generation_api/service by Matt Grill

javascript, api, service

JavaScript