Rails - Mar 2005 - Beginner question: serverside singletons?

Hello all, just started tinkering with Rails after reading all the hype about 
it. I''m a raw novice with Ruby and (obviously) Rails, but have
extensive
experience with serverside Java (J2EE stack, Tapestry, etc). Rails looks 
cool, though embedding Ruby code in HTML reminds me unpleasantly of JSP + 
Struts and I''m deeply suspicious of all the behind-the-scenes magic
going on
in Rails. But I''ll bury my misgivings and give this thing a whirl :).

Anyway, a question: with Java servlets (and servlet-based frameworks)
I''m used
to being able to initialize some "expensive" stuff at app startup as 
singletons and then store them away (servlet context, JNDI, whatever) for 
later use by the app request-handling code. Now, this is obviously impossible 
with straight cgi-script style Rails with separate script invocations per 
request, but can I do something like this with Webrick, mod_ruby etc?

As a concrete example, I''d like to initialize a Copland registry as a 
singleton when a Rails app starts up, and then use that in the Rails code to 
fetch my own code modules when I need them. Can I do this, and if yes
what''s
the appropriate place in Rails to plug in the initialization code?

All help appreciated.

//Petri

Petri Wessman wrote:
> As a concrete example, I''d like to initialize a Copland registry
as a
> singleton when a Rails app starts up, and then use that in the Rails code
to
> fetch my own code modules when I need them. Can I do this, and if yes
what''s
> the appropriate place in Rails to plug in the initialization code?
config/environment.rb is run when a new app instance is started.

Set up your registry in config/registry.rb and add
  require ''config/registry''
to the end of config/environment.rb

Have you seen Needle?  It''s Copland''s successor.

Best,
jeremy

On Wednesday 30 March 2005 20:36, Jeremy Kemper wrote:
> Petri Wessman wrote:
> > As a concrete example, I''d like to initialize a Copland
registry as a
> > singleton when a Rails app starts up, and then use that in the Rails
code
> > to fetch my own code modules when I need them. Can I do this, and if
yes
> > what''s the appropriate place in Rails to plug in the
initialization code?
>
> config/environment.rb is run when a new app instance is started.
>
> Set up your registry in config/registry.rb and add
>   require ''config/registry''
> to the end of config/environment.rb
Ok, thanks, that sounds pretty nice and elegant. I had already figured out 
that environment.rb is probably the right place, but it''s nice to have
that
confirmed :).
> Have you seen Needle?  It''s Copland''s successor.
> Best,
> jeremy
Heard of it but haven''t taken a look until a few minutes ago, I
hadn''t
realized that it''s Copland''s successor, I had thought it ws
"just" another
IoC container. But thanks, if it''s the one getting active development
then
it''s obviously the way to go. I like HiveMind on the Java side, and
googling
originally turned Copland up first. IoC is one of those things that you
don''t
want to give up once you get used to it, it''s a damn good way of 
compartmentaizing and building modular code (IMHO, of course).

Ok, off to tinker some more... ;)

//Petri