var Client = require('ftp');
var c = new Client();

c.on('ready', callback);
c.on('error', function(err){
    console.log(err);
});
c.on('close', function(err){
    console.log(err);
});
c.on('end', function(){
    console.log("END");
});

c.connect({
    host: host,
    port: port,
    user: username,
    password: password
});
...
c.put(uploadfile, uploadpath, onupload);