NAME
Config::Onion - Layered configuration, because configs are like ogres
VERSION
version 1.000
SYNOPSIS
my $cfg = Config::Onion->new;
my $cfg = Config::Onion->set_default(db => {name => 'foo', password => 'bar'});
my $cfg = Config::Onion->load('/etc/myapp', './myapp');
my $cfg = Config::Onion->load_glob('./plugins/*');
$cfg->set_default(font => 'Comic Sans');
$cfg->load('config');
$cfg->load_glob('conf.d/myapp*');
$cfg->set_override(font => 'Arial');
my $dbname = $cfg->get->{db}{name};
my $plain_hashref_conf = $cfg->get;
my $dbpassword = $plain_hashref_conf->{db}{password};
DESCRIPTION
All too often, configuration is not a universal or one-time thing, yet
most configuration-handling treats it as such. Perhaps you can only load
one config file. If you can load more than one, you often have to load
all of them at the same time or each is stored completely independently,
preventing one from being able to override another. Config::Onion
changes that.
Config::Onion stores all configuration settings in four layers:
Defaults, Main, Local, and Override. Each layer can be added to as many
times as you like. Within each layer, settings which are given multiple
times will take the last specified value, while those which are not
repeated will remain untouched.
$cfg->set_default(name => 'Arthur Dent', location => 'Earth');
$cfg->set_default(location => 'Magrathea');
# In the Default layer, 'name' is still 'Arthur Dent', but 'location' has
# been changed to 'Magrathea'.
Regardless of the order in which they are set, values in Main will
always override values in the Default layer, the Local layer always
overrides both Default and Main, and the Override layer overrides all
the others.
The design intent for each layer is:
* Default
Hardcoded default values to be used when no further configuration is
present
* Main
Values loaded from standard configuration files shipped with the
application
* Local
Values loaded from local configuration files which are kept separate
to prevent them from being overwritten by application upgrades, etc.
* Override
Settings provided at run-time which take precendence over all
configuration files, such as settings provided via command line
switches
METHODS
new
Returns a new, empty configuration object.
load(@file_stems)
Loads files matching the given stems using "Config::Any->load_stems"
into the Main layer. Also concatenates ".local" to each stem and loads
matching files into the Local layer. e.g., "$cfg->load('myapp')" would
load "myapp.yml" into Main and "myapp.local.js" into Local. All filename
extensions supported by "Config::Any" are recognized along with their
corresponding formats.
load_glob(@globs)
Uses the Perl "glob" function to expand each parameter into a list of
filenames and loads each file using "Config::Any". Files whose names
contain the string ".local." are loaded into the Local layer. All other
files are loaded into the Main layer.
set_default([\%settings,...,] %settings)
set_override([\%settings,...,] %settings)
Imports %settings into the Default or Override layer. Accepts settings
both as a plain hash and as hash references, but, if the two are mixed,
all hash references must appear at the beginning of the parameter list,
before any non-hashref settings.
PROPERTIES
cfg
get
Returns the complete configuration as a hash reference.
default
main
local
override
These properties each return a single layer of the configuration. This
is not likely to be useful other than for debugging. For most other
purposes, you probably want to use "get" instead.
BUGS AND LIMITATIONS
No bugs have been reported.
Please report any bugs or feature requests at
<https://github.com/dsheroh/Config-Onion/issues>
AUTHOR
Dave Sherohman <dsheroh@cpan.org>
COPYRIGHT AND LICENSE
This software is copyright (c) 2013 by Lund University Library.
This is free software; you can redistribute it and/or modify it under
the same terms as the Perl 5 programming language system itself.
POD ERRORS
Hey! The above document had some coding errors, which are explained
below:
Around line 168:
You forgot a '=back' before '=head1'