server.coffee

require.paths.unshift './vendor'

Twitter = require './twitter'

# ...

app.get '/sign_in', (req, res)->
  Twitter.consumer.getOAuthRequestToken (error, token, secret, url, params)->
    # save it to the session

# Hard-coded URL for callback (OAuth 1.0)
app.get '/oauth/callback', (req, res)->
  Twitter.consumer.getOAuthAccessToken req.session['req.token'], req.session['req.secret'], (error, access_token, access_secret, params)->
    # voila, access token acquired

twitter.coffee

require.paths.unshift './vendor'
sys = require 'sys'
OAuth = require('oauth').OAuth
Consumer = new OAuth(
  'http://api.twitter.com/oauth/request_token', 
  'http://api.twitter.com/oauth/access_token', 
  process.env.TWITTER_KEY, 
  process.env.TWITTER_SECRET, 
  '1.0', null, 'HMAC-SHA1'
)

Client = (token, secret)->
  this.token = token
  this.secret = secret
  
Client.prototype.request = (method, path, callback)->
  url = "http://api.twitter.com/1#{path}"
  sys.puts "[Twitter] Fetching #{path}"
  Consumer.getProtectedResource url, method, this.token, this.secret, (error, data, response)->
    if error
      sys.puts sys.inspect(error)
    else
      callback JSON.parse(data)
    
Client.prototype.get = (path, callback)->
  this.request 'GET', path, callback

exports.consumer = Consumer
exports.client = Client