From: Robert Klemme <shortcutter@...>
Date: 2009-05-05T16:58:11+09:00
Subject: Re: modules and classes question

2009/5/4 Marcelo Barbudas <nostef@gmail.com>:
> Hi,
>>
>>  class SpecializedResource < BaseResource
>>    def SpecializedResource.meth
>>      sr = SpecializedResource.new
>>      sr.do_stuff
>>    end
>>  end
>
> This seems a little complicated, not very DRY to write this code for every
> method.
>
> How does AWS do it?
>
> AWS::S3::Base.establish_connection!()
> and then just:
> Bucket.create('jukebox')

I do not have insights into AWS beyond what can be gatherere from
http://amazon.rubyforge.org/.  I don't find this pattern very
appealing.  For something like this to work you need to resort to some
form of global state (global variable, constant, class instance
variable, thread local variable) which means there is potential for
problems when working with multiple threads.  Another issue is that it
is not obvious, i.e. you do not see that there is something
transported behind the scenes.

I would at least refrain from placing this pattern in a library unless
it is thread safe and it is sure that there will and can never be the
need for more than a single connection which seems doubtful in case of
AWS.

My 0.02EUR.

Kind regards

robert

-- 
remember.guy do |as, often| as.you_can - without end
http://blog.rubybestpractices.com/