|1.||Dispatching to a particular paged based on the state of the application is performed according to param field.|
|2.||The name of the state is appended to an application-wide package prefix to determine an appropriate class to handle the request.|
|3.||The package for the class is autoloaded if needed.|
|4.||The template for the class replaces .pm with .tt (configurable), found in the same @INC path, and is therefore likely to be in the same directory.|
|5.||A wrapper template is automatically provided.|
The default class is My::App, but this can be overridden. The default state is welcome, but this too can be overridden. The default hidden param name for the state is _state, and if you think this can be overridden, you are correct. See the trend here?
A sample app is the best way to show all of this, of course. We dont have one yet... thats on the TODO list. However, the functions have all been exercised in the tests for this module, including an artificial application, so check that out for at least an example of the interfaces.
These methods or values are the ones youll most likely change in your application, although you can leave them all alone and itll still be a valid framework to create your entire application.
config_state_param The name of the hidden field which will contain the state, defaulting to _state.
In any form you create, or any constructed URL, you must be sure to include this param as part of the form so that the right response can be matched up for the submitted data. For example:
config_class_prefix The class prefix placed ahead of the state name, default My::App. For example, the controller class for the welcome state will be <My::App::welcome>.
Note that the template also use this name as their prefix, so that your controller and template files end up in the same directory.
config_default_page The initial page if the state is missing, default welcome. config_wrapper The name of the WRAPPER template, default My/App/WRAPPER.tt.
If you change config_class_prefix, youll want to change this as well so that WRAPPER.tt ends up in the right directory. (I debated doing that for you so you could just say "WRAPPER.TT", but thatd make more complicated versions of this callback be even more and more complicated.)
[% PROCESS $template %]
However, typically, youll want to define app-wide blocks and variables, and maybe wrap the statement above in an exception catcher. For example:
[%- TRY; content = PROCESS $template; self.CGI.header; self.CGI.start_html; content; self.CGI.end_html; ### exceptions ## for errors: CATCH; CLEAR; self.CGI.header(text/plain); -%] An error has occurred. Remain calm. Authorities have been notified. Do not leave the general area. [%- FILTER stderr -%] ** [% template.filename %] error: [% error.info %] ** [% END; # FILTER END; # TRY -%]
This sends back a plain message to the browser, as well as logging the precise error text to STDERR, and hopefully the web error log.
config_compile_dir The location of the compiled Perl templates, default "/tmp/compile-dir.$<" (where $< is the current users numeric user ID). Youll want this to be some place that the process can write, but nobody else can. The default is functional, but not immune to other hostile users on the same box, so youll want to override that for those cases. config_tt_extension The suffix replacing .pm when the module name is mapped to the template name. By default, its .tt.
You will most likely not need to change these, but youll want to stay away from their names.
name_to_page Called with a page name, returns a page object. Will also autoload the package. plugin <B>This is still an experimental feature that will be reworked in future releases.B>
Called with a page name, returns a new page object that can be used as self in a template, mixing in the code from the pages class for additional heavy lifting.
For example, to have a subpage plugin, create a subpage.tt and subpage.pm file, then include the tt with:
Now, within subpage.tt, calls to self.SomeMethod will first search the original pages lineage, and then the plugin class lineage for a definition for SomeMethod.
dispatch Overridden from CGI::Prototype. Selects either the hidden field state, or the default state, and returns the page object. shortname Returns the simple name for the current page object by stripping off the config_class_prefix. Note that this will fail in the event of prototype page constructed on the fly, rather than a named class. Hmm, Ill have to think about what that implies. render_enter Overridden from CGI::Prototype. Forces the hidden state param to the shortname of the current object, then calls render_enter_per_page. render_enter_per_page If you need page-specific render_enter items, put them here. The default definition does nothing. This is to keep from having to call superclass methods for render_enter. respond Overridden from CGI::Prototype. Calls respond_per_app and then respond_per_page, looking for a true value, which is then returned.
If you have site-wide buttons (like a button-bar on the side or top of your form), look for them in respond_per_app, and return the new page from there. Otherwise, return undef, and itll fall through to the per-page response.
respond_per_app A hook for application-wide responses, defaulting to undef. Should return either a page object (to be rendered) or a false value (selecting the per-page respond). respond_per_page If respond_per_app returns false, this hook is then evaluated. It should return a page object to be rendered. The default returns the current page object, so you stay here for rendering. template Overridden from CGI::Prototype. Returns the name of a template, defined by replacing the double-colons in the classname of the current page with forward slashes, and then appending .tt (by default, see config_tt_extension). Because @INC is added to the INCLUDE_PATH for the engine, this <B>shouldB> find the .tt file in the same directory as the .pm file. engine_config Overridden from CGI::Prototype, so that the cached Template object that is essentially:
Please report any bugs or feature requests to email@example.com, or through the web interface at http://rt.cpan.org. I will be notified, and then youll automatically be notified of progress on your bug as I make changes.
Randal L. Schwartz, <firstname.lastname@example.org>
Special thanks to Geekcruises.com and an unnamed large university for providing funding for the development of this module.
Copyright (C) 2003, 2004, 2005 by Randal L. Schwartz
This library is free software; you can redistribute it and/or modify it under the same terms as Perl itself, either Perl version 5.8.5 or, at your option, any later version of Perl 5 you may have available.
|perl v5.20.3||CGI::PROTOTYPE::HIDDEN (3)||2011-07-30|