Clean way of transfering Objects between childinit and request handlers ?

[Greg Cope <gj...@rubberplant.freeserve.co.uk>]

Dear All

I want to create an Object in a ChildInit handler and then pass it to
request handlers.

Its a DB Object / module and it does some initialiastion, it prepares a
few statment handles and then stores them in an array for later
execution.

One solution is to create a the object in a child init handler and to
store it in a package global - and then to use a type glob to referance
it from other handlers by using that package global (detailed below).

However this appears as a bit of a kludge and does not have any repect
for encapsulation ;-).

I feel there must be a cleaner way of doing this ? A read of the guide
etc ... has not given me any clues.

Any ideas appreciated.

Greg Cope

### type glob example (off the top of my head - could be wrong)

package child_init;

use vars qw($foo);

$foo = My::db_handler->new();

#######

package request_handler;

*db = \$child_init::foo;

$db->foo();

Re: Clean way of transfering Objects between childinit and requesthandlers ?

[Greg Cope <gj...@rubberplant.freeserve.co.uk>]

Matt Sergeant wrote:
> 
> On Sun, 17 Sep 2000, Chris Winters wrote:
> 
> > Hi Greg,
> >
> > Check out Class::Singleton for this purpose. Works great for me.
> >

.....
<snippage>
 
> One thing C::Singleton misses is a clear_instance method though, which is
> pretty much necessary for mod_perl work (I'm surprised Andy hasn't fixed
> this, since he does a lot of mod_perl stuff)...
> 
> However copying the code is pretty trivial and adding that method is about
> another 3 lines.

Thanks gents - I'd not seen this one before.

Oh, Chris I think your ratio is a bit low - the actual module code is
extremely short.

Greg


> 
> --
> <Matt/>
> 
> Fastnet Software Ltd. High Performance Web Specialists
> Providing mod_perl, XML, Sybase and Oracle solutions
> Email for training and consultancy availability.
> http://sergeant.org | AxKit: http://axkit.org

Re: Clean way of transfering Objects between childinit and request handlers ?

[Matt Sergeant <ma...@sergeant.org>]

On Sun, 17 Sep 2000, Chris Winters wrote:

> Hi Greg,
> 
> Check out Class::Singleton for this purpose. Works great for me.
> 
> Basically, the first time you create the object, do:
> 
>  my $obj = $object_class->instance( ... );
> 
> Every successive time you want the object, just call:
> 
>  my $obj = $object_class->instance;
> 
> And you'll get the same object back. Initialization stuff (such as
> database connects, whatever) is put in the _new_instance() method,
> which is called when the object is created but not when the object is
> returned. 
> 
> The object is stored in the class itself, and Class::Singleton is
> actually a really simple module (probably a 10-to-1 ratio of
> documentation-to-code), but it's nice to have a consistent, standard
> way of doing things.

One thing C::Singleton misses is a clear_instance method though, which is
pretty much necessary for mod_perl work (I'm surprised Andy hasn't fixed
this, since he does a lot of mod_perl stuff)...

However copying the code is pretty trivial and adding that method is about
another 3 lines.

-- 
<Matt/>

Fastnet Software Ltd. High Performance Web Specialists
Providing mod_perl, XML, Sybase and Oracle solutions
Email for training and consultancy availability.
http://sergeant.org | AxKit: http://axkit.org

Re: Clean way of transfering Objects between childinit and request handlers ?

[Chris Winters <cw...@intes.net>]

* Greg Cope (gjjc@rubberplant.freeserve.co.uk) [000917 14:31]:
> Dear All
> 
> I want to create an Object in a ChildInit handler and then pass it to
> request handlers.
> 
> Its a DB Object / module and it does some initialiastion, it prepares a
> few statment handles and then stores them in an array for later
> execution.
> 
> One solution is to create a the object in a child init handler and to
> store it in a package global - and then to use a type glob to referance
> it from other handlers by using that package global (detailed below).
> 
> However this appears as a bit of a kludge and does not have any repect
> for encapsulation ;-).
> 
> I feel there must be a cleaner way of doing this ? A read of the guide
> etc ... has not given me any clues.
> 
> Any ideas appreciated.
> 
> Greg Cope

Hi Greg,

Check out Class::Singleton for this purpose. Works great for me.

Basically, the first time you create the object, do:

 my $obj = $object_class->instance( ... );

Every successive time you want the object, just call:

 my $obj = $object_class->instance;

And you'll get the same object back. Initialization stuff (such as
database connects, whatever) is put in the _new_instance() method,
which is called when the object is created but not when the object is
returned. 

The object is stored in the class itself, and Class::Singleton is
actually a really simple module (probably a 10-to-1 ratio of
documentation-to-code), but it's nice to have a consistent, standard
way of doing things.

Chris

-- 
Chris Winters
Senior Internet Developer    intes.net
cwinters@intes.net           http://www.intes.net/
Integrated hardware/software solutions to make the Internet work for you.