librato/librato-rails — pull request #25 by bensie (2012-11-04 20:07:02+00:00)
Title: Fix checking for Passenger as current app server

::PhusionPassenger is the proper constant to check for as of Passenger 3.x. With the Passenger 4 beta, AbstractServer was removed.

Phusion guys recommend only checking for ::PhusionPassenger, no need for AbstractServer (even in 3.x).