Facebook get a long life access token

gistfile1.txt

1. Get an access_token

https://www.facebook.com/dialog/oauth?
  client_id=XXX&
  client_secret=XXX&
  redirect_uri=XXX&
  scope=publish_stream,offline_access,read_stream,manage_pages&
  response_type=token

2. Get a long lasting access_token

https://graph.facebook.com/oauth/access_token?
  grant_type=fb_exchange_token&
  client_id=XXX&
  client_secret=XXX&
  fb_exchange_token=XXX