NAME¶
CGI::Application::Plugin::ConfigAuto - Easy config file management for
CGI::Application
SYNOPSIS¶
use CGI::Application::Plugin::ConfigAuto (qw/cfg/);
In your instance script:
my $app = WebApp->new(PARAMS => { cfg_file => 'config.pl' });
$app->run();
In your application module:
sub my_run_mode {
my $self = shift;
# Access a config hash key directly
$self->cfg('field');
# Return config as hash
%CFG = $self->cfg;
}
DESCRIPTION¶
CGI::Application::Plugin::ConfigAuto adds easy access to config file variables
to your CGI::Application modules. Lazy loading is used to prevent the config
file from being parsed if no configuration variables are accessed during the
request. In other words, the config file is not parsed until it is actually
needed. The Config::Auto package provides the framework for this plugin.
RATIONALE¶
"CGI::Application" promotes re-usable applications by moving a maximal
amount of code into modules. For an application to be fully re-usable without
code changes, it is also necessary to store configuration variables in a
separate file.
This plugin supports multiple config files for a single application, allowing
config files to override each other in a particular order. This covers even
complex cases, where you have a global config file, and second local config
file which overrides a few variables.
It is recommended that you to declare your config file locations in the instance
scripts, where it will have minimum impact on your application. This technique
is ideal when you intend to reuse your module to support multiple
configuration files. If you have an application with multiple instance scripts
which share a single config file, you may prefer to call the plugin from the
setup() method.
DECLARING CONFIG FILE LOCATIONS¶
# In your instance script
# value can also be an arrayref of config files
my $app = WebApp->new(PARAMS => { cfg_file => 'config.pl' })
# OR ...
# Pass in an array of config files, and they will be processed in order.
$app->cfg_file('../../config/config.pl');
Your config files should be referenced using the syntax example above. Note that
the key "config_files" can be used as alternative to cfg_file.
The format is detected automatically using Config::Auto. It it known to support
the following formats: colon separated, space separated, equals separated,
XML, Perl code, and Windows INI. See that modules documentation for complete
details.
METHODS¶
cfg()¶
# Access a config hash key directly
$self->cfg('field');
# Return config as hash
my %CFG = $self->cfg;
# return as hashref
my $cfg_href = $self->cfg;
A method to access project configuration variables. The config file is parsed on
the first call with a perl hash representation stored in memory. Subsequent
calls will use this version, rather than re-reading the file.
In list context, it returns the configuration data as a hash. In scalar context,
it returns the configuration data as a hashref.
config()¶
"
config()" in CGI::Application::Standard::Config is provided
as an alias to
cfg() for compliance with
CGI::Application::Standard::Config. It always exported by default per the
standard.
std_config()¶
"
std_config()" in CGI::Application::Standard::Config is
implemented to comply with CGI::Application::Standard::Config. It's for
developers. Users can ignore it.
cfg_file()¶
# Usual
$self->cfg_file('my_config_file.pl');
# Supply the first format, guess the second
$self->cfg_file('my_config_file.pl',{ format => 'perl' } );
Supply an array of config files, and they will be processed in order. If a hash
reference if found it, will be used to supply the format for the previous file
in the array.
Perl¶
Here's a simple example of my favorite config file format: Perl. Having the
"shebang" line at the top helps "Config::Auto" to identify
it as a Perl file. Also, be sure that your last statement returns a hash
reference.
#!/usr/bin/perl
my %CFG = ();
# directory path name
$CFG{DIR} = '/home/mark/www';
# website URL
$CFG{URL} = 'http://mark.stosberg.com/';
\%CFG;
SEE ALSO¶
CGI::Application CGI::Application::Plugin::ValidateRM
CGI::Application::Plugin::DBH CGI::Application::Standard::Config.
perl(1)
AUTHOR¶
Mark Stosberg "mark@summersault.com"
LICENSE¶
Copyright (C) 2004 - 2011 Mark Stosberg "mark@summersault.com"
This library is free software. You can modify and or distribute it under the
same terms as Perl itself.