module Typhoeus::EasyFu::Callbacks

def failure

or curl returns an error code
gets called when finished and response code is 300-599 
def failure
  @failure.call(self) if @failure
end

def on_failure(&block) 

def on_failure(&block)
  @failure = block
end

def on_failure=(block) 

def on_failure=(block)
  @failure = block
end

def on_success(&block) 

def on_success(&block)
  @success = block
end

def on_success=(block) 

def on_success=(block)
  @success = block
end

def success

or curl returns an error code.
gets called when finished and response code is not 2xx, 
def success
  @success.call(self) if @success
end