class Excon::Middleware::Base

def error_call(datum)
  # do stuff
  @stack.error_call(datum)
end

def initialize(stack)
  @stack = stack
end

def request_call(datum)
  # do stuff
  @stack.request_call(datum)
end

def response_call(datum)
  @stack.response_call(datum)
  # do stuff
end