[cgiapp] CGI::Application status update from the maintainer

[Ron Savage]

Hi Brett

On 07/09/12 00:48, B. Estrade wrote:
> What I mean is that there are 2 methods that basically do the same
> thing.  If you have MyApp (ISA CGI::Application), you would initialize
> runmodes and whatnot via cgiapp_init.  Say you subclass MyApp to get
> MyApp::Foo, but want to keep what is going on in MyApp::cgiapp_init;
> but you have your own specific MyApp::Foo runmodes. You'd most cleanly
> do this by defining MyApp::Foo::setup. Now, what if you want to
> subclass MyApp::Foo into MyApp::Foo::Derp, but you have some Derp
> specific runmodes.  You end up having to redefine cgiapp_init or
> setup; in either case, you're going to have to make an explicit call
> to SUPER::cgiapp_init or SUPER::setup.
>
> You're limited to 2 generations below CAP if you want to subclass
> without explicitly calling on SUPER because you have 2 explicit
> methods -cgiapp_init and setup.  I am suggesting a way to provide any
> number of generations without having to call on SUPER.

Rhesa has replied with one (slightly more complex) way of doing things. 
Here is another:

package WebCommon;
use base 'CGI::Application';

sub cgi_init # or setup
{
	$self -> web_common_init;
}

package WebAPI;
use base 'WebCommon';

sub cgi_init # or setup
{
	$self -> web_api_init;
}

package WebAPI::Stuff;
use base 'WebAPI';

sub cgi_init # or setup
{
	$self -> web_api_stuff_init;
}

The 3 new subs can be stand-alone or call each other or call common 
code. They can do whatever you think best.

The point is that the sub-class cgi_inits are overridden by the /normal/ 
operation of CAP, and hence are called at the appropriate time 
/automatically/.

Obviously you can call SUPER::cgi_init or SUPER::anything if you wish.

(Sometimes of course calling a super class's method is mandatory. For 
instance, with CGI::Snapp, a sub-class must call SUPER::_init($arg), as 
in the demo. But that's to initialize object-level variables, having 
nothing to do with what we're talking about.)

The problem is that SUPER::* is a way of sharing /all/ the code in the 
super class's cgi_init.

If you don't wish to do that, then do as I've indicated above, and just 
share none or some of the code via web_common_init etc. You really do 
have a variety of ways to work.

Lastly, there is no limit on the depth of nesting possible.

-- 
Ron Savage
http://savage.net.au/
Ph: 0421 920 622