I'm used to write two runmodes for every panel in my application. In your case, they would be login and login_update. Given a method redirect to set the appropriate headers, the code could be the following (not-so-pseudo-code): 
# Does nothing except printing the form.
# Using sessions you can pass to it an error_message,
# for example.
#
sub login                                                             
+          
{   
    my $self = shift;                                                 
+          
    
    my $tmpl = $self->load_tmpl( 'login' );                           
+          
    
    return $tmpl->output();                                           
+          
}   

sub login_update                                                      
+          
{   
    my $self = shift;                                                 
+          
    my $q    = $self->query;
  
    # Fetch username and password from the form
    #  
    
    if ( PASSWORD CORRECT ) {        
        
        $self->redirect( { rm => 'first_panel' } );           
    }
    else {

        # It could store some useful info in a session,
        # for example the error message.
        #
        $self->redirect( { rm => 'login' } );
    }

    return;
}

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I use this technique a lot, and it has proven its flexibility and efficiency.

In reply to Re: CGI::Application design strategy by larsen
in thread CGI::Application design strategy by BUU

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