For documentation, see the Bitly Repo.
A Bitly
object is exposed to the global scope so that you can directly use it like this:
var bitly = new Bitly('<YOUR USERNAME>', '<YOUR API KEY>');
bitly.shorten('https://github.com/tanepiper/node-bitly', function(err, response) {
if (err) throw err;
// See http://code.google.com/p/bitly-api/wiki/ApiDocumentation for format of returned object
var short_url = response.data.url
// Do something with data
});