Apache2::Controller::X - Exception::Class hierarchy for Apache2::Controller

Version 1.000.111

 package MyApp::C::Foo;
 use base qw( Apache2::Controller MyApp::Blabber ); 
 use Apache2::Controller::X;
 # ...
 sub some_page_controller_method {
    my ($self, @path_args) = @_;
    $self->print( $self->blabber() || a2cx "Cannot blabber: $OS_ERROR" );
 }

 # or subclass and extend the errors...

 package MyApp::X;
 use base qw( Apache2::Controller::X );
 use Exception::Class (
     'MyApp::X' => { 
         isa => 'Apache2::Controller::X',
         fields => [qw( message status dump action )],
     },
     alias => 'myx',
 );

 package MyApp::C::Bar;
 use base qw( Apache2::Controller );
 use Apache2::Const -compile => qw( :http );
 use MyApp::X;
 # ...
 sub page_controller_method {
     myx  message => q{ You're not supposed to be here. },
          status => Apache2::Const::FORBIDDEN,
          action => sub {"not sure how you'd implement this actually"},
          dump => {
            this    => q{structure will get YAML::Syck::Dump'd},
            that    => [qw( to the error log )],
          };
 }

TODO: when $X is intercepted by handler() in each of the controller layers, attach it to pnotes.

Hierarchy of Exception::Class objects for Apache2::Controller. All are subclasses of Apache2::Controller::X.

All Apache2::Controller::X exceptions implement three fields:

Required. The standard Exception::Class message field. If you call throw() or the alias a2cx() with only one argument, a string, then this gets set as the message field, which is displayed when the object is referred to in string context.

 eval { a2cx "booyeah" };
 if (my $X = Exception::Class->caught('Apache2::Controller::X')) {
     warn "my exception 'message' was '$X'\n";
     warn $X->trace;
 }

This can be set to an :http in Apache2::Const constant, which will then be set as the status for the request.

 a2cx message => "oh no!",
      status => Apache2::Const::HTTP_INTERNAL_SERVER_ERROR;

Combined with status, when intercepted by handler in Apache2::Controller this sets a custom message with status_line in Apache2::RequestRec.

 a2cx message => "Warp injection coil failure in unit 3-A-73",
     status => Apache2::Const::HTTP_INTERNAL_SERVER_ERROR,
     status_line => "Turbulence ahead. Please buckle your safety belts.";

This differentiation can be used to display technical information in the log while giving a nice message to the user.

If error in Apache2::Controller::Render::Template is used, status_line is preferentially used to translate the error code, otherwise it uses status_message in HTTP::Status.

An arbitrary data structure which Apache2::Controller will send through YAML::Syck Dump() when printing to the error log.

The basic exception object that implements the three basic fields.

After abandoning redirects, I have no use for any subclasses. Should not re-invent the wheel, after all. Just set the outgoing location header and return REDIRECT from a controller if you want to do that. Or other actions should be done.

This is the Fields() method provided by Exception::Class. For some reason the pod test wants this method enumerated.

Exception::Class

Apache2::Controller

Apache2::Controller::NonResponseBase

Apache2::Controller::NonResponseRequest

Mark Hedges, <hedges ||at formdata.biz>

Copyright 2008-2010 Mark Hedges, all rights reserved.

This program is free software; you can redistribute it and/or modify it under the same terms as Perl itself.

This software is provided as-is, with no warranty and no guarantee of fitness for any particular purpose.