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Catalyst::Plugin::ConfigLoader - Load config files of various types


    package MyApp;
    # ConfigLoader should be first in your list so
    # other plugins can get the config information
    use Catalyst qw( ConfigLoader ... );
    # by default myapp.* will be loaded
    # you can specify a file if you'd like
    __PACKAGE__->config( 'Plugin::ConfigLoader' => { file => 'config.yaml' } );    

  In the file, assuming it's in YAML format:

    foo: bar

  Accessible through the context object, or the class itself

   $c->config->{foo}    # bar
   MyApp->config->{foo} # bar


This module will attempt to load find and load a configuration file of various types. Currently it supports YAML, JSON, XML, INI and Perl formats. Special configuration for a particular driver format can be stored in MyApp->config->{ 'Plugin::ConfigLoader' }->{ driver }. For example, to pass arguments to Config::General, use the following:

    __PACKAGE__->config( 'Plugin::ConfigLoader' => {
        driver => {
            'General' => { -LowerCaseNames => 1 }
    } );

See Config::Any's driver_args parameter for more information.

To support the distinction between development and production environments, this module will also attemp to load a local config (e.g. myapp_local.yaml) which will override any duplicate settings.


setup( )

This method is automatically called by Catalyst's setup routine. It will attempt to use each plugin and, once a file has been successfully loaded, set the config() section.


This method handles loading the configuration data into the Catalyst context object. It does not return a value.


This method determines the potential file paths to be used for config loading. It returns an array of paths (up to the filename less the extension) to pass to Config::Any for loading.


This method determines the path, filename prefix and file extension to be used for config loading. It returns the path (up to the filename less the extension) to check and the specific extension to use (if it was specified).

The order of preference is specified as:



  • $c->config->{ 'Plugin::ConfigLoader' }->{ file }

  • $c->path_to( $application_prefix )

If either of the first two user-specified options are directories, the application prefix will be added on to the end of the path.


Determines the suffix of files used to override the main config. By default this value is local, but it can be specified in the following order of preference:



  • $c->config->{ 'Plugin::ConfigLoader' }->{ config_local_suffix }


This method is called after the config file is loaded. It can be used to implement tuning of config values that can only be done at runtime. If you need to do this to properly configure any plugins, it's important to load ConfigLoader before them. ConfigLoader provides a default finalize_config method which walks through the loaded config hash and calls the config_substitutions sub on any string.

config_substitutions( $value )

This method substitutes macros found with calls to a function. There are three default macros:

  • __HOME__ - replaced with $c->path_to('')

  • __path_to(foo/bar)__ - replaced with $c->path_to('foo/bar')

  • __literal(__FOO__)__ - leaves __FOO__ alone (allows you to use __DATA__ as a config value, for example)

The parameter list is split on comma (,). You can override this method to do your own string munging, or you can define your own macros in MyApp->config->{ 'Plugin::ConfigLoader' }->{ substitutions }. Example:

    MyApp->config->{ 'Plugin::ConfigLoader' }->{ substitutions } = {
        baz => sub { my $c = shift; qux( @_ ); }

The above will respond to __baz(x,y)__ in config strings.


Brian Cassidy <>


The following people have generously donated their time to the development of this module:

  • Joel Bernstein <> - Rewrite to use Config::Any

  • David Kamholz <> - Data::Visitor integration

Work to this module has been generously sponsored by:


Copyright 2006-2009 by Brian Cassidy

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