Phusion Passenger problems

When you are running under Apache / Phusion Passenger and get the following error:

RuntimeError: PhusionPassenger::Utils::RewindableInput is not a valid input stream. It must walk like either a String, an IO, or a Source.

you need to create a file in config/initializers containing the following:

module ImprovedRewindableInput
  def readline(*args)
    make_rewindable unless @rewindable_io
    @rewindable_io.readline(*args)
  end
  
  def size
    make_rewindable unless @rewindable_io
    @rewindable_io.size
  end

  def getc
    make_rewindable unless @rewindable_io
    @rewindable_io.getc
  end

  def ungetc(*args)
    make_rewindable unless @rewindable_io
    @rewindable_io.ungetc(*args)
  end

  def eof?
    make_rewindable unless @rewindable_io
    @rewindable_io.eof?
  end

  def nil?
    make_rewindable unless @rewindable_io
    @rewindable_io.nil?
  end
end

if defined?(PhusionPassenger::Utils::RewindableInput)
  PhusionPassenger::Utils::RewindableInput.send(:include, ImprovedRewindableInput)
elsif defined?(Rack::RewindableInput)
  Rack::RewindableInput.send(:include, ImprovedRewindableInput)
end

Source: Gavin Terrill’s Blog

This is confirmed to work under Rails 3.1 and Ruby 1.9.3.