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package Config::MVP::Reader::Finder;
BEGIN {
$Config::MVP::Reader::Finder::VERSION = '2.101650';
}
use Moose;
extends 'Config::MVP::Reader';
# ABSTRACT: a reader that finds an appropriate file
use Module::Pluggable::Object;
use Try::Tiny;
sub default_search_path {
return qw(Config::MVP::Reader)
}
has _module_pluggable_object => (
is => 'ro',
init_arg => undef,
default => sub {
my ($self) = @_;
Module::Pluggable::Object->new(
search_path => [ $self->default_search_path ],
inner => 0,
require => 1,
);
},
);
sub _which_reader {
my ($self, $location) = @_;
my @options;
for my $pkg ($self->_module_pluggable_object->plugins) {
next unless $pkg->isa('Moose::Object');
next unless $pkg->does('Config::MVP::Reader::Findable');
my $location = $pkg->refined_location($location);
next unless defined $location;
push @options, [ $pkg, $location ];
}
confess "no viable configuration could be found" unless @options;
# XXX: Improve this error message -- rjbs, 2010-05-24
confess "multiple possible config plugins found" if @options > 1;
return {
'package' => $options[0][0],
'location' => $options[0][1],
};
}
has if_none => (
is => 'ro',
isa => 'Maybe[Str|CodeRef]',
);
sub read_config {
my ($self, $location, $arg) = @_;
$self = $self->new unless blessed($self);
$arg ||= {};
local $arg->{assembler} = $arg->{assembler} || $self->build_assembler;
my $which;
my $instead;
try {
$which = $self->_which_reader($location);
} catch {
die $_ unless $_ =~ /^no viable configuration/;
die $_ unless defined (my $handler = $self->if_none);
$instead = $self->$handler($location, $arg);
};
return $instead unless $which;
my $reader = $which->{package}->new;
return $reader->read_config( $which->{location}, $arg );
}
sub build_assembler { }
sub read_into_assembler {
confess "This method should never be called or reachable";
}
no Moose;
__PACKAGE__->meta->make_immutable;
1;
__END__
=pod
=head1 NAME
Config::MVP::Reader::Finder - a reader that finds an appropriate file
=head1 VERSION
version 2.101650
=head1 DESCRIPTION
The Finder reader multiplexes many other readers that implement the
L<Config::MVP::Reader::Findable> role. It uses L<Module::Pluggable> to search
for modules, limits them to objects implementing the Findable role, and then
selects the those which report that they are able to read a configuration file
found in the config root directory. If exactly one findable configuration
reader finds a file, it is used to read the file and the configuration sequence
is returned. Otherwise, an exception is raised.
Config::MVP::Reader::Finder's C<build_assembler> method will decline a new
assembler, so if none was passed to C<read_config>, the Findable reader to
which reading is delegated will be responsible for building the assembler,
unless a Finder subclass overrides C<build_assembler> to set a default across
all possible delegates.
=head1 METHODS
=head2 default_search_path
This is the default search path used to find configuration readers. This
method should return a list, and by default returns:
qw( Config::MVP::Reader )
=head1 AUTHOR
Ricardo Signes <rjbs@cpan.org>
=head1 COPYRIGHT AND LICENSE
This software is copyright (c) 2010 by Ricardo Signes.
This is free software; you can redistribute it and/or modify it under
the same terms as the Perl 5 programming language system itself.
=cut
|
