Re: Advice needed on custom webapp framework

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Jonathan Vanasco wrote:

> package Website1;
> my  $DB = new Website1::DB();
>     # make a new ref for the website
> sub handler
> {
>     my     $r         = shift;
>     my     $user     = new Website::User( \$r, \$DB );
>      my     $page     = new Website::Page( \$user , \$DB );
>     my     $html     = $page->processRequest();
> }
>
> what i would like is:
> sub handler
> {
>     my     $r         = shift;
>     my     $user     = new Website::User( \$r );
>      my     $page     = new Website::Page( \$user );
>     my     $html     = $page->processRequest();
> }
>
> now, i guess what i'm trying to do within
>     Website1::User
>     Website1::Page
> is access the
>     $DB in the base of Website1 that i define just before the handler
> BUT
>     I'm trying to do so in a way that both:
>         Website1::PackageName
>         Website2::PackageName
>         WebAppFramework::PackageName
>     Will all retreive the correct DB from the script that defines the 
> handler
>

Ok. This means you want to make your Website::User and Website::Page 
more intelligent. If I got you right the only thing have to implement
for each user is Website1::DBI and Website2::DBI.

What you really need here when talking about Pattern-Programming is a 
"Factory-Class" which creates the
appropiate WebAppFramework::DBI-Sub-Class for you and design all your 
Website*::DBI-classes as "Singletons".

===================8<===================
package WebAppFramework::DBIFactory;

sub getDb {
    my $dbiModule = shift;
    require($dbiModule); ## load the apprioate module
    return $dbiModule->instance(); ## get an instance of the module
}

1;
===================8<===================

===================8<===================
package WebAppFramework::User;

sub new {
    my $class = shift;
    my $r = shift;

    my $this =
    {
       db => 
WebAppFramework::DBIFactory::getDb($r->dir_config("DBIModule"));
    };

    bless $this, $class;
}

1;
===================8<===================

===================8<===================
<Location /webapp1>
    PerlSetVar DBIModule Website1::DBI
</Location>

<Location /webapp2>
    PerlSetVar DBIModule Website2::DBI
</Location>
===================8<===================

Hope I got you right? If you don't want to use config values you could 
also use the name of the package
in the handler e.g. Website1, Website2 and add "::DBI" in your factory 
method.

Tom

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