NAME
   CGI::Application::Plugin::Config::General - Add Config::General Support
   to CGI::Application

VERSION
   Version 0.08

NOTE
   This module is obsolete and has now been superceded by
   CGI::Application::Plugin::Config::Context.

SYNOPSIS
 Simple Access to Configuration
   In your CGI::Application-based module:

       use base 'CGI::Application';
       use CGI::Application::Plugin::Config::General;

       sub cgiapp_init {
           my $self = shift;

           # Set config file and other options
           $self->conf->init(
               -ConfigFile => 'app.conf',
           );
       }

       sub my_run_mode {
           my $self = shift;

           # get entire configuration
           my %conf = $self->conf->getall;

           # get entire configuration (as a reference)
           my $conf = $self->conf->getall;

           # get single config parameter
           my $value = $self->conf->param('some_value');

           # get underlying Config::General::Match object
           my $obj = $self->conf->obj;
       }

 Configuration Based on URL or Module
   You can match a configuration section to the request URL, or to the
   module name. For instance, given the following configuration file:

       admin_area    = 0

       <AppMatch ^MyApp::Admin>
           admin_area = 1
           title      = Admin Area
       </AppMatch>

       <Location /cgi-bin/feedback.cgi>
           title      = Feedback Form
       </Location>

   The configuration will depend on how the script is called:

       # URL:      /cgi-bin/feedback.cgi?rm=add
       # Module:   MyApp::Feedback

       print $self->conf->param('admin_area');  # 0
       print $self->conf->param('title');       # 'Feedback Form'

       # URL:      /cgi-bin/admin/users.cgi
       # Module:   MyApp::Admin::Users

       print $self->conf->param('admin_area');  # 1
       print $self->conf->param('title');       # 'Admin Area'

 Matching Configuration based on a Virtual Host
   This module can also pick a configuration section based on the current
   virtual-host:

       # httpd.conf
       <VirtualHost _default_:8080>
           SetEnv SITE_NAME REDSITE
       </VirtualHost>

       # in app.conf
       <Site BLUESITE>
           background = blue
           foreground = white
       </Site>

       <Site REDSITE>
           background = red
           foreground = pink
       </Site>

       <Site GREENSITE>
           background = darkgreen
           foreground = lightgreen
       </Site>

DESCRIPTION
   This module allows you to easily access configuration data stored in
   Config::General (i.e. Apache-style) config files.

   You can also automatically match configuration sections to the request
   URL, or to the module name. This is similar to how Apache dynamically
   selects a configuration by matching the request URL to e.g. "<Location>"
   and "<LocationMatch>" sections.

   You can also select configuration sections based on Virtual Host or by a
   variable you set in an ".htaccess" file. This allows you to share a
   single application between many virtual hosts, each with its own unique
   configuration. This could be useful, for instance, in providing multiple
   themes for a single application.

 Simple access to Configuration
   This module provides a "conf" method to your CGI::Application object.
   First, you initialize the configuration system (typically in your
   "cgiapp_init" method):

       $self->conf->init(
           -ConfigFile => 'app.conf',
       );

   The configuration file is parsed at this point and is available from
   this point on.

   Then, within your run-modes you can retrieve configuration data:

       # get entire configuration
       my %conf = $self->conf->getall;
       my $value = $conf{'some_value'};

       # get entire configuration (as a reference)
       my $conf = $self->conf->getall;
       my $value = $conf->{'some_value'};

       # get single config parameter
       my $value = $self->conf->param('some_value');

 Multiple named Configurations
   You can use more than one configuration by providing a name to the
   "conf" method:

       $self->conf('database')->init(
           -ConfigFile => 'app.conf',
       );
       $self->conf('application')->init(
           -ConfigFile => 'app.conf',
       );

       ...

       my %db_config  = $self->conf('database')->getall;
       my %app_config = $self->conf('application')->getall;

 Configuration based on URL or Module
   Within your configuration file, you can provide different configurations
   depending on the current URL, or on the package name of your
   application.

   <Site>
       Matches against the "SITE_NAME" environment variable, using an
       *exact* match.

           # httpd.conf
           <VirtualHost _default_:8080>
               SetEnv SITE_NAME REDSITE
           </VirtualHost>

           # in app.conf
           <Site BLUESITE>
               background = blue
               foreground = white
           </Site>

           <Site REDSITE>
               background = red
               foreground = pink
           </Site>

           <Site GREENSITE>
               background = darkgreen
               foreground = lightgreen
           </Site>

       You can use name your sections something other than "<Site>", and
       you can use a different environment variable than "SITE_NAME". See
       "Notes on Site Matching", below.

   <App>
       Matches the Package name of your application module, for instance:

           <App ABC_Books::Admin>
               ...
           </App>

       The match is performed hierachically, like a filesystem path, except
       using "::" as a delimiter, instead of "/". The match is tied to the
       beginning of the package name, just like absolute paths. For
       instance, given the section:

           <App Site::Admin>
               ...
           </App>

       the packages "Site::Admin" and "Site::Admin::Users" would match, but
       the packages "My::Site::Admin" and "Site::Administrative" would not.

   <AppMatch>
       Matches the package name of your application module, using a regular
       expression. The expression is not tied to the start of the string.
       For instance, given the section:

           <AppMatch Site::Admin>
               ...
           </AppMatch>

       The following packages would all match: "Site::Admin",
       "Site::Admin::Users", "My::Site::Admin", "MySite::Admin",
       "Site::Administrative".

   <Location>
       Matches hierarchically against the request URI, including the path
       and the "PATH_INFO" components, but *excluding* the scheme, host,
       port and query string.

       So, for instance with the following URL:

           http://bookstore.example.com/cgi-bin/category.cgi/fiction/?rm=list

       The Location would be:

           /cgi-bin/category.cgi/fiction/

       Internally, the location is obtained by calling the "url" method of
       the query object (which is usually either a CGI or CGI::Simple
       object):

           $path = $webapp->query->url('-absolute' => 1, '-path_info' => 1);

   <LocationMatch>
       Matches against the request URI, using a regular expression.

 Section Merge Order
   The sections are matched in the following order:

       Site:         <Site>
       Package Name: <App>      and <AppMatch>
       URL:          <Location> and <LocationMatch>

   When there is more than one matching section at the same level of
   priority (e.g. two "<Location>" sections, or both an "<App>" and an
   "<AppMatch>" section), then the sections are merged in the order of
   shortest match first.

   Values in sections matched later override the values in sections matched
   earlier.

   The idea is that the longer matches are more specific and should have
   priority, and that URIs are more specific than Module names.

 Section Nesting
   The sections can be nested inside each other. For instance:

       <Site BOOKSHOP>
           <Location /admin>
               admin_books = 1
           </Location>
       </Site>

       <Location /admin>
           <Site RECORDSHOP>
               admin_records = 1
           </Site>
       </Location>

       <App Bookshop::>
           <App Admin::>
           </App>
       </App>

   By default, the sections can be nested up to two levels deep. You can
   change this by setting the -NestingDepth parameter to init.

 Merging Configuration Values into your Template
   You can easily pass values from your configuration files directly to
   your templates. This allows you to associate HTML titles with URLs, or
   keep text like copyright notices in your config file instead of your
   templates:

       copyright_notice    =  Copyright (C) 1492 Christopher Columbus

       <Location /about>
           title = "Manifest Destiny, Inc. -  About Us"
       </Location>

       <Location /contact>
           title = "Manifest Destiny, Inc. - Contact Us"
       </Location>

   If you use HTML::Template, you use the associate method when you load
   the template:

       $self->load_template(
           'template.tmpl',
           'associate' => $self->conf,
       );

   If you use Template::Toolkit (via the CGI::Application::Plugin::TT
   module), you can accomplish the same thing by providing a custom
   tt_pre_process method:

       sub tt_pre_process {
           my $self            = shift;
           my $template        = shift;
           my $template_params = shift;

           my $config = $self->conf->getall
           foreach (keys %$config) {
               unless (exists $template_params->{$_}) {
                   $template_params->{$_} = $config->{$_};
               }
           }
       }

   *NOTE: If you plan to merge data directly from your config files to
   your* *templates, you should consider keeping your database passwords
   and other* *sensitive data in a separate configuration file, in order to
   avoid* *accidentally leaking these data into your web pages.*

METHODS
 init
   Initializes the plugin. The only required parameter is a config file:

       $self->conf->init(
           -ConfigFile => 'app.conf',
       );

   The other paramters are described below:

   -ConfigFile
       The path to the configuration file to be parsed.

   -Options
       Any additional Config::General::Match options. See the documentation
       to Config::General and Config::General::Match for more details.

   -CacheConfigFiles
       Whether or not to cache configuration files. Enabled, by default.
       This option is only really useful in a persistent environment such
       as "mod_perl". See "Config File Caching" under "ADVANCED USAGE",
       below.

   -StatConfig
       If config file caching is enabled, this option controls how often
       the config files are checked to see if they have changed. The
       default is 60 seconds. This option is only really useful in a
       persistent environment such as "mod_perl". See "Config File Caching"
       under "ADVANCED USAGE", below.

   -SiteSectionName
       Change the name of the "<Site>" section to something else. For
       instance, to use sections named "<VirtualHost>", use:

           -SiteSectionName => 'VirtualHost'

   -SiteVar
       Change the name of the "SITE_NAME" environment variable used to
       match against "<Site>" sections. For instance To change this name to
       "HTTP_HOST", use:

           -SiteVar => 'HTTP_HOST',

   -NestingDepth
       The number of levels deep that sections can be nested. The default
       is two levels deep.

       See "Section Nesting", above.

   You can initialize the plugin from within your instance CGI script:

       my $app = WebApp->new();
       $app->conf->init(-ConfigFile => '../../config/app.conf');
       $app->run();

   Or you can do so from within your "cgiapp_init" method within the
   application:

       sub cgiapp_init {
           my $self = shift;
           $self->conf->init(
               -ConfigFile => "$ENV{DOCUMENT_ROOT}/../config/app.conf"
           );
       }

 getall
   Gets the entire configuration as a hash or hashref:

       my %config = $self->conf->getall;  # as hash
       my $config = $self->conf->getall;  # as hashref

   Note that the following two method calls will return different results:

       my %config = $self->conf->getall;       # parsed config
       my %config = $self->conf->obj->getall;  # raw config

   In the first case, the matching based on URI, Module, etc. has already
   been performed. In the second case, you get the raw config with all of
   the "<Location>", "<App>", etc. sections intact.

 param
   Allows you to retrieve individual values from the configuration.

   It behvaves like the "param" method in other classes, such as CGI,
   CGI::Application and HTML::Template:

       $value      = $self->conf->param('some_key');
       @all_keys   = $self->conf->param();

 obj
   Provides access to the underlying Config::General::Match object.

   You can access the raw unparsed configuration data by calling

       my $config = $self->conf->obj->getall;  # raw config

   See the note under getall, above.

   In future versions of this module, certain caching strategies may
   prevent you from accessing the underlying Config::General::Match object
   in certain situations.

 get_current_config ($name)
   This is a class method which returns the current configuration object.

       my $conf = CGI::Application::Plugin::Config::General->get_current_config;
       print $conf->{'title'};

       my %db_conf = CGI::Application::Plugin::Config::General->get_current_config('db');
       print $db_conf{'username'};

   This method is most useful in situations where you don't have access to
   the CGI::Application object, such within a Class::DBI class. See "Access
   to Configuration information from another Class" for an example.

   Note that get_current_config returns the configuration hash (or hashref)
   directly, and does not give you access to the object itself. It is the
   equivalent of calling "$self->conf->getall".

ADVANCED USAGE
 Usage in a Persistent Environment such as mod_perl
   The following sections describe some notes about running this module
   under mod_perl:

  Config File Caching
   By default each config file is read only once when the conf object is
   first initialized. Thereafter, on each init, the cached config is used.

   This means that in a persistent environment like mod_perl, the config
   file is parsed on the first request, but not on subsequent requests.

   If enough time has passed (sixty seconds by default) the config file is
   checked to see if it has changed. If it has changed, then the file is
   reread.

   If you are using Config::General version 2.28 or greater, then you can
   safely use the "include" feature of Config::General and all included
   files will be checked for changes along with the main file.

   To disable caching of config files pass a false value to the
   -CacheConfigFiles parameter to init, e.g:

       $self->conf->init(
           -ConfigFile           => 'app.conf',
           -CacheConfigFiles     => 0,
       );

   To change how often config files are checked for changes, change the
   value of the -StatConfig paramter to init, e.g.:

       $self->conf->init(
           -ConfigFile => 'app.conf',
           -StatConfig => 1, # check the config file every second
       );

   Internally the configuration cache is implemented by a hash, keyed by
   the absolute path of the configuration file. This means that if you have
   two web applications that use the same configuration file, they will use
   the same cache.

   This would only matter if you wanted to use different "Config::General"
   or "Config::General::Match" options for different applications running
   in the same process that use the same config file.

  PerlSetVar instead of SetEnv
   For a (slight) performance improvement, you can use "PerlSetVar" instead
   of "SetEnv" within a "<VirtualHost>":

       # httpd.conf
       <VirtualHost _default_:8080>
           PerlSetVar SITE_NAME REDSITE
       </VirtualHost>

 Notes on Site Matching
  Renaming "<Site>" or "SITE_NAME"
   Normally, the environment variable "SITE_NAME" is matched to "<Site>"
   section.

   You can change these with the -SiteSectionName and -SiteVar parameters
   to init:

       $self->conf->init(
           -ConfigFile           => 'app.conf',
           -SiteSectionName      => 'Host',
           -SiteVar              => 'MY_HOST',
       );

   This will match the environment variable "MY_HOST" to the "<Host>"
   section.

  Setting "SITE_NAME" from an ".htaccess" file or the CGI script
   Since "SITE_NAME" is just an environment variable, you can set it
   anywhere you can set environment variables. For instance in an
   ".htaccess" file:

       # .htaccess
       SetEnv SITE_NAME bookshop

   Or even the calling CGI script:

       #!/usr/bin/perl

       use MySite::WebApp;

       $ENV{'SITE_NAME'} = 'recordshop';
       my $app = MySite::WebApp->new();
       $app->run();

 Access to Configuration information from another Class
   You can also get at the current configuration settings from a completely
   unrelated Perl module. This can be useful for instance if you need to
   configure a set of Class::DBI classes, and you want them to be able to
   pick up their configuration on their own. For instance:

       # app.conf

       <database>
           connect_string = dbi:Pg:dbname=example
           username       = test
           password       = test

           <options>
               RaiseError = 1
               AutoCommit = 1
           </options>
       </database>


       # In your Class::DBI subclass
       package My::Class::DBI::Base;
       use base 'Class::DBI';

       sub db_Main {

           my $conf = CGI::Application::Plugin::Config::General->get_current_config;

           my $dsn  = $conf->{'database'}{'connect_string'};
           my $user = $conf->{'database'}{'username'};
           my $pass = $conf->{'database'}{'password'};
           my $opts = $conf->{'database'}{'options'};

           return DBI->connect_cached($dsn, $user, $pass, $opts);
       }

   For this example to work, you need to make sure you call
   "$self->conf->init" before you access the database through any of your
   Class::DBI objects.

   Note that get_current_config returns the configuration hash (or hashref)
   directly, and does not give you access to the object itself. It is the
   equivalent of calling "$self->conf->getall".

 Changing Parsing Behaviour Using Custom -MatchSections
   Internally, this module uses Config::General and Config::General::Match
   to parse its config files. If you want to change the parsing behaviour,
   you can pass your own -MatchSections list to init. For instance, if you
   want to allow only sections named "<URL>", with no nesting, and have
   these matched exactly to the complete request path, you could do the
   following:

       # app.conf

       admin_area = 0
       user_area  = 0

       <URL /cgi-bin/admin.cgi>
           admin_area = 1
       </URL>

       <URL /cgi-bin/user.cgi>
           user_area = 1
       </URL>


       # in your cgiapp_init:
       $self->conf->init(
           -ConfigFile        => 'app.conf',
           -NestingDepth      => 1,
           -Options           => {
               -MatchSections => [
                   {
                       -Name          => 'URL',
                       -MatchType     => 'exact',
                       -MergePriority => 0,
                       -SectionType   => 'path',
                   },
               ]
           }
       );

   For reference, here is the default -MatchSections:

       -MatchSections => [
           {
               -Name          => 'Site', # overridden by -SiteSectionName
               -MatchType     => 'exact',
               -MergePriority => 0,
               -SectionType   => 'env',
           },
           {
               -Name          => 'AppMatch',
               -MatchType     => 'regex',
               -SectionType   => 'module',
               -MergePriority => 1,
           },
           {
               -Name              => 'App',
               -MatchType         => 'path',
               -PathPathSeparator => '::',
               -SectionType       => 'module',
               -MergePriority     => 1,
           },
           {
               -Name          => 'LocationMatch',
               -MatchType     => 'regex',
               -SectionType   => 'path',
               -MergePriority => 3,
           },
           {
               -Name          => 'Location',
               -MatchType     => 'path',
               -SectionType   => 'path',
               -MergePriority => 3,
           },
       ],

   For each section, the -SectionType param indicates what runtime variable
   the section will be matched against. Here are the allowed values

       env:     matched to the environment variable SITE_NAME (overridden by -SiteNameVar)
       module:  name of the Perl Module handling this request (e.g. MyApp::Users)
       path:    path of the request, including path_info (e.g. /cgi-bin/myapp/users.cgi/some/path)

   You can use the above -SectionType values in your own custom
   -MatchSections.

   For more information on the syntax of -MatchSections, see the docs for
   Config::General::Match.

AUTHOR
   Michael Graham, "<[email protected]>"

BUGS
   Please report any bugs or feature requests to
   "[email protected]", or through the
   web interface at <http://rt.cpan.org>. I will be notified, and then
   you'll automatically be notified of progress on your bug as I make
   changes.

ACKNOWLEDGEMENTS
   This module would not be possible without Thomas Linden's excellent
   Config::General module.

   Thanks to the excellent examples provided by the other CGI::Application
   plugin authors: Mark Stosberg, Michael Peters, Cees Hek and others.

SOURCE
   The source code repository for this module can be found at
   http://github.com/mgraham/CAP-Config-General

SEE ALSO
       CGI::Application
       Config::General
       Config::General::Match
       CGI::Application::Plugin::Config::Simple
       CGI::Application::Plugin::ConfigAuto

       CGI::Application::Plugin::TT
       Template::Toolkit
       HTML::Template

COPYRIGHT & LICENSE
   Copyright 2005 Michael Graham, All Rights Reserved.

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

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