more code updates, before i look in depth at the _load() routine
[p5sagit/Config-Any.git] / lib / Config / Any.pm
CommitLineData
c80a0905 1package Config::Any;
92a04e78 2
c80a0905 3use strict;
92a04e78 4use warnings;
5
c80a0905 6use Carp;
7use Module::Pluggable::Object ();
59a80452 8
4efab558 9our $VERSION = '0.09';
c80a0905 10
59a80452 11=head1 NAME
12
13Config::Any - Load configuration from different file formats, transparently
14
15=head1 VERSION
16
7c218182 17This document describes Config::Any version 0.09
59a80452 18
19=head1 SYNOPSIS
20
21 use Config::Any;
22
f0e3c221 23 my $cfg = Config::Any->load_stems({stems => \@filepath_stems, ... });
24 # or
25 my $cfg = Config::Any->load_files({files => \@filepaths, ... });
59a80452 26
f0e3c221 27 for (@$cfg) {
28 my ($filename, $config) = each %$_;
29 $class->config($config);
30 warn "loaded config from file: $filename";
31 }
59a80452 32
33=head1 DESCRIPTION
34
35L<Config::Any|Config::Any> provides a facility for Perl applications and libraries
36to load configuration data from multiple different file formats. It supports XML, YAML,
37JSON, Apache-style configuration, Windows INI files, and even Perl code.
38
39The rationale for this module is as follows: Perl programs are deployed on many different
40platforms and integrated with many different systems. Systems administrators and end
41users may prefer different configuration formats than the developers. The flexibility
42inherent in a multiple format configuration loader allows different users to make
43different choices, without generating extra work for the developers. As a developer
44you only need to learn a single interface to be able to use the power of different
45configuration formats.
46
47=head1 INTERFACE
48
49=cut
50
7c218182 51=head2 load_files( \%args )
59a80452 52
4efab558 53 Config::Any->load_files( { files => \@files } );
54 Config::Any->load_files( { files => \@files, filter => \&filter } );
55 Config::Any->load_files( { files => \@files, use_ext => 1 } );
59a80452 56
57C<load_files()> attempts to load configuration from the list of files passed in
58the C<files> parameter, if the file exists.
59
60If the C<filter> parameter is set, it is used as a callback to modify the configuration
61data before it is returned. It will be passed a single hash-reference parameter which
62it should modify in-place.
63
64If the C<use_ext> parameter is defined, the loader will attempt to parse the file
65extension from each filename and will skip the file unless it matches a standard
66extension for the loading plugins. Only plugins whose standard extensions match the
67file extension will be used. For efficiency reasons, its use is encouraged, but
68be aware that you will lose flexibility -- for example, a file called C<myapp.cfg>
69containing YAML data will not be offered to the YAML plugin, whereas C<myapp.yml>
70or C<myapp.yaml> would be.
71
41f47406 72C<load_files()> also supports a 'force_plugins' parameter, whose value should be an
73arrayref of plugin names like C<Config::Any::INI>. Its intended use is to allow the use
74of a non-standard file extension while forcing it to be offered to a particular parser.
75It is not compatible with 'use_ext'.
76
ef87b7dc 77You can supply a C<driver_args> hashref to pass special options to a particular
78parser object. Example:
79
80 Config::Any->load_files( { files => \@files, driver_args => {
81 General => { -LowerCaseNames => 1 }
82 } )
83
59a80452 84=cut
85
c80a0905 86sub load_files {
92a04e78 87 my ( $class, $args ) = @_;
4efab558 88
89 unless ( $args && exists $args->{ files } ) {
90 warn "No files specified!";
59a80452 91 return;
92 }
93
4efab558 94 return $class->_load( $args );
c80a0905 95}
96
7c218182 97=head2 load_stems( \%args )
59a80452 98
bef9e9a5 99 Config::Any->load_stems( { stems => \@stems } );
100 Config::Any->load_stems( { stems => \@stems, filter => \&filter } );
101 Config::Any->load_stems( { stems => \@stems, use_ext => 1 } );
59a80452 102
103C<load_stems()> attempts to load configuration from a list of files which it generates
104by combining the filename stems list passed in the C<stems> parameter with the
105potential filename extensions from each loader, which you can check with the
106C<extensions()> classmethod described below. Once this list of possible filenames is
107built it is treated exactly as in C<load_files()> above, as which it takes the same
108parameters. Please read the C<load_files()> documentation before using this method.
109
110=cut
111
c80a0905 112sub load_stems {
92a04e78 113 my ( $class, $args ) = @_;
bef9e9a5 114
115 unless ( $args && exists $args->{ stems } ) {
116 warn "No stems specified!";
59a80452 117 return;
118 }
92a04e78 119
bef9e9a5 120 my $stems = delete $args->{ stems };
c80a0905 121 my @files;
92a04e78 122 for my $s ( @$stems ) {
92a04e78 123 for my $ext ( $class->extensions ) {
4efab558 124 push @files, "$s.$ext";
c80a0905 125 }
126 }
c80a0905 127
bef9e9a5 128 $args->{ files } = \@files;
129 return $class->_load( $args );
130}
41f47406 131
59a80452 132# this is where we do the real work
133# it's a private class-method because users should use the interface described
134# in the POD.
c80a0905 135sub _load {
92a04e78 136 my ( $class, $args ) = @_;
137 my ( $files_ref, $filter_cb, $use_ext, $force_plugins_ref )
138 = @{ $args }{ qw(files filter use_ext force_plugins) };
c80a0905 139 croak "_load requires a arrayref of file paths" unless defined $files_ref;
140
bef9e9a5 141 my %files = map { $_ => 1 } @$files_ref;
142 my %force_plugins = map { $_ => 1 } @$force_plugins_ref;
7c218182 143 my $enforcing = keys %force_plugins ? 1 : 0;
41f47406 144
92a04e78 145 my $final_configs = [];
146 my $originally_loaded = {};
c80a0905 147
41f47406 148 # perform a separate file loop for each loader
c80a0905 149 for my $loader ( $class->plugins ) {
92a04e78 150 next if $enforcing && not defined $force_plugins{ $loader };
f0e3c221 151 last unless keys %files;
bef9e9a5 152 my %ext = map { $_ => 1 } $loader->extensions;
41f47406 153
92a04e78 154 my ( $loader_class ) = $loader =~ /::([^:]+)$/;
155 my $driver_args = $args->{ driver_args }{ $loader_class } || {};
156
157 FILE:
158 for my $filename ( keys %files ) {
4efab558 159 next unless -f $filename;
92a04e78 160
161 # use file extension to decide whether this loader should try this file
162 # use_ext => 1 hits this block
163 if ( defined $use_ext && !$enforcing ) {
f0e3c221 164 my $matched_ext = 0;
92a04e78 165 EXT:
166 for my $e ( keys %ext ) {
167 next EXT unless $filename =~ m{ \. $e \z }xms;
168 next FILE unless exists $ext{ $e };
f0e3c221 169 $matched_ext = 1;
59a80452 170 }
41f47406 171
f0e3c221 172 next FILE unless $matched_ext;
59a80452 173 }
174
175 my $config;
92a04e78 176 eval { $config = $loader->load( $filename, $driver_args ); };
41f47406 177
7c218182 178 next if $@; # if it croaked or warned, we can't use it
c80a0905 179 next if !$config;
92a04e78 180 delete $files{ $filename };
41f47406 181
182 # post-process config with a filter callback, if we got one
c80a0905 183 $filter_cb->( $config ) if defined $filter_cb;
41f47406 184
c80a0905 185 push @$final_configs, { $filename => $config };
186 }
187 }
7c218182 188
189 return $final_configs;
c80a0905 190}
191
59a80452 192=head2 finder( )
193
194The C<finder()> classmethod returns the
195L<Module::Pluggable::Object|Module::Pluggable::Object>
196object which is used to load the plugins. See the documentation for that module for
197more information.
198
199=cut
200
c80a0905 201sub finder {
92a04e78 202 my $class = shift;
c80a0905 203 my $finder = Module::Pluggable::Object->new(
204 search_path => [ __PACKAGE__ ],
205 require => 1
206 );
bef9e9a5 207 return $finder;
c80a0905 208}
209
59a80452 210=head2 plugins( )
211
212The C<plugins()> classmethod returns the names of configuration loading plugins as
213found by L<Module::Pluggable::Object|Module::Pluggable::Object>.
214
215=cut
216
c80a0905 217sub plugins {
218 my $class = shift;
219 return $class->finder->plugins;
220}
221
59a80452 222=head2 extensions( )
c80a0905 223
59a80452 224The C<extensions()> classmethod returns the possible file extensions which can be loaded
225by C<load_stems()> and C<load_files()>. This may be useful if you set the C<use_ext>
226parameter to those methods.
c80a0905 227
59a80452 228=cut
c80a0905 229
59a80452 230sub extensions {
231 my $class = shift;
232 my @ext = map { $_->extensions } $class->plugins;
4efab558 233 return wantarray ? @ext : \@ext;
59a80452 234}
c80a0905 235
236=head1 DIAGNOSTICS
237
c80a0905 238=over
239
7c218182 240=item C<No files specified!> or C<No stems specified!>
c80a0905 241
59a80452 242The C<load_files()> and C<load_stems()> methods will issue this warning if
243called with an empty list of files/stems to load.
c80a0905 244
59a80452 245=item C<_load requires a arrayref of file paths>
c80a0905 246
59a80452 247This fatal error will be thrown by the internal C<_load> method. It should not occur
248but is specified here for completeness. If your code dies with this error, please
249email a failing test case to the authors below.
c80a0905 250
251=back
252
c80a0905 253=head1 CONFIGURATION AND ENVIRONMENT
254
c80a0905 255Config::Any requires no configuration files or environment variables.
256
c80a0905 257=head1 DEPENDENCIES
258
59a80452 259L<Module::Pluggable|Module::Pluggable>
c80a0905 260
59a80452 261And at least one of the following:
262L<Config::General|Config::General>
263L<Config::Tiny|Config::Tiny>
264L<JSON|JSON>
265L<YAML|YAML>
266L<JSON::Syck|JSON::Syck>
267L<YAML::Syck|YAML::Syck>
268L<XML::Simple|XML::Simple>
c80a0905 269
270=head1 INCOMPATIBILITIES
271
c80a0905 272None reported.
273
c80a0905 274=head1 BUGS AND LIMITATIONS
275
c80a0905 276No bugs have been reported.
277
278Please report any bugs or feature requests to
279C<bug-config-any@rt.cpan.org>, or through the web interface at
280L<http://rt.cpan.org>.
281
c80a0905 282=head1 AUTHOR
283
f0e3c221 284Joel Bernstein E<lt>rataxis@cpan.orgE<gt>
c80a0905 285
59a80452 286=head1 CONTRIBUTORS
287
288This module was based on the original
289L<Catalyst::Plugin::ConfigLoader|Catalyst::Plugin::ConfigLoader>
290module by Brian Cassidy C<< <bricas@cpan.org> >>.
291
292With ideas and support from Matt S Trout C<< <mst@shadowcatsystems.co.uk> >>.
c80a0905 293
41f47406 294Further enhancements suggested by Evan Kaufman C<< <evank@cpan.org> >>.
295
c80a0905 296=head1 LICENCE AND COPYRIGHT
297
298Copyright (c) 2006, Portugal Telecom C<< http://www.sapo.pt/ >>. All rights reserved.
41f47406 299Portions copyright 2007, Joel Bernstein C<< <rataxis@cpan.org> >>.
c80a0905 300
301This module is free software; you can redistribute it and/or
302modify it under the same terms as Perl itself. See L<perlartistic>.
303
c80a0905 304=head1 DISCLAIMER OF WARRANTY
305
306BECAUSE THIS SOFTWARE IS LICENSED FREE OF CHARGE, THERE IS NO WARRANTY
307FOR THE SOFTWARE, TO THE EXTENT PERMITTED BY APPLICABLE LAW. EXCEPT WHEN
308OTHERWISE STATED IN WRITING THE COPYRIGHT HOLDERS AND/OR OTHER PARTIES
309PROVIDE THE SOFTWARE "AS IS" WITHOUT WARRANTY OF ANY KIND, EITHER
310EXPRESSED OR IMPLIED, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
311WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. THE
312ENTIRE RISK AS TO THE QUALITY AND PERFORMANCE OF THE SOFTWARE IS WITH
313YOU. SHOULD THE SOFTWARE PROVE DEFECTIVE, YOU ASSUME THE COST OF ALL
314NECESSARY SERVICING, REPAIR, OR CORRECTION.
315
316IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN WRITING
317WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MAY MODIFY AND/OR
318REDISTRIBUTE THE SOFTWARE AS PERMITTED BY THE ABOVE LICENCE, BE
319LIABLE TO YOU FOR DAMAGES, INCLUDING ANY GENERAL, SPECIAL, INCIDENTAL,
320OR CONSEQUENTIAL DAMAGES ARISING OUT OF THE USE OR INABILITY TO USE
321THE SOFTWARE (INCLUDING BUT NOT LIMITED TO LOSS OF DATA OR DATA BEING
322RENDERED INACCURATE OR LOSSES SUSTAINED BY YOU OR THIRD PARTIES OR A
323FAILURE OF THE SOFTWARE TO OPERATE WITH ANY OTHER SOFTWARE), EVEN IF
324SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE POSSIBILITY OF
325SUCH DAMAGES.
59a80452 326
327=head1 SEE ALSO
328
329L<Catalyst::Plugin::ConfigLoader|Catalyst::Plugin::ConfigLoader>
330-- now a wrapper around this module.
331
332=cut
333
41f47406 334"Drink more beer";