Bytes transfered

client.js

Client.prototype.download = function(src, dest, callback) {
  var self = this;
  var intervalId;

  self.sftp(function(err,sftp){
    if (err) {
      return callback(err);
    }

    var sftp_readStream = sftp.createReadStream(src);
    sftp_readStream.on('error', function(err){
      callback(err);
    });
    fsDest = fs.createWriteStream(dest);
    intervalId = setInterval(function() {
      self.emit('transfer', fsDest.bytesWritten);
    }, 5000);
    sftp_readStream.pipe(fsDest)
    .on('close',function(){
      clearInterval(intervalId);
      self.emit('read', src);
      callback(null);
    })
    .on('error', function(err){
      clearInterval(intervalId);
      callback(err);
    });
  });
};