video-info.js

var path = require('path');
var express     = require('express');
var nunjucks    = require('nunjucks');
var app         = express();
var ytdl = require("youtube-dl");
var request = require("request");
var utils = require('utility');
// view engine setup
nunjucks.configure('views', {
    autoescape: true,
    express: app
});
// uncomment after placing your favicon in /public
app.use(express.static(path.join(__dirname, 'public')));

// catch 404 and forward to error handler
function mapInfo(item) {
  'use strict';
  return {itag: item.format_id,
   filetype: item.ext, 
   resolution: item.resolution||(item.width +'x'+item.height),
   url:item.url,
   c_url:utils.base64encode(item.url),
   filesize:item.size,
 };
}
app.get('/',function(req,res){
  res.render('index.html');
})

app.get('/download', function (req, res) {
  var url = req.query.url;
ytdl.getInfo(url, function(err, info) {
  'use strict';
  if (err) { res.send(err); }
  else {
      var formats = info.formats
      var streams = []
      var audio_streams =[]
      if (typeof formats === 'undefined') {
        streams_info = [{url:info.url,filetype:info.ext,resolution:'unknown'}]
        audio_info = [{url:info.url,filetype:info.ext,resolution:'unknown'}]
      } 
      else {
        for(var i=0;i<formats.length;i++){
          //streams with video and audio
          if (formats[i].vcodec !="none" && formats[i].acodec !="none") {
              streams.push(formats[i]);
                //console.log(formats[i]);
          }
          else if(formats[i].vcodec ="none" && formats[i].acodec !="none"){
            audio_streams.push(formats[i]);
          }

        }
        var streams_info = streams.map(mapInfo);
        var audio_info = audio_streams.map(mapInfo);
      }
      var v ={ url:url,
              extractor:info.extractor,
              title:info.title,
              thumbnail:info.thumbnail,
              duration:info.duration,
              description:info.description,
              published:info.upload_date,
              uploader:info.uploader,
              view_count:info.view_count,
              video:streams_info,
            audio:audio_info};
      //console.log(formats);
      res.render('download.html',v);
  }
});

});

// development error handler
// will print stacktrace


// production error handler
// no stacktraces leaked to user
app.use(function(err, req, res, next) {
  res.status(err.status || 500);
  res.render('error', {
    message: err.message,
    error: {}
  });
});


module.exports = app;