package Dancer::Config::Object; use strict; use warnings; use base 'Exporter'; use Carp 'croak'; use Dancer::Exception qw(:all); use Scalar::Util 'blessed'; register_exception('BadConfigMethod', message_pattern => qq{Can't locate config attribute "%s".\nAvailable attributes: %s}); our @EXPORT_OK = qw(hashref_to_object); { my $index = 1; sub hashref_to_object { my ($hashref) = @_; my $class = __PACKAGE__; my $target = "${class}::__ANON__$index"; $index++; if ('HASH' ne ref $hashref) { if ( blessed $hashref ) { # we have already converted this to an object. This can happen # in cases where Dancer::Config->load is called more than # once. return $hashref; } else { # should never happen raise 'Core::Config' => "Argument to $class must be a hashref"; } } my $object = bless $hashref => $target; _add_methods($object); return $object; } } sub _add_methods { my ($object) = @_; my $target = ref $object; foreach my $key ( keys %$object ) { my $value = $object->{$key}; if ( 'HASH' eq ref $value ) { $value = hashref_to_object($value); } elsif ( 'ARRAY' eq ref $value ) { foreach (@$value) { $_ = 'HASH' eq ref($_) ? hashref_to_object($_) : $_; } } # match a (more or less) valid identifier next unless $key =~ qr/^[[:alpha:]_][[:word:]]*$/; my $method = "${target}::$key"; no strict 'refs'; *$method = sub {$value}; } _setup_bad_method_trap($target); } # AUTOLOAD will only be called if a non-existent method is called. It's used # to generate the list of available methods. It's slow, but we're going to # die. Who wants to die quickly? sub _setup_bad_method_trap { my ($target) = @_; no strict; ## no critic (ProhibitNoStrict) *{"${target}::AUTOLOAD"} = sub { $AUTOLOAD =~ /.*::(.*)$/; # should never happen my $bad_method = $1 ## no critic (ProhibitCaptureWithoutTest) or croak "Could not determine method called via $AUTOLOAD"; return if 'DESTROY' eq $bad_method; my $symbol_table = "${target}::"; # In these fake classes, we only have methods my $methods = join ', ' => grep { !/^(?:AUTOLOAD|DESTROY|$bad_method)$/ } sort keys %$symbol_table; raise BadConfigMethod => $bad_method, $methods; }; } 1; __END__ =pod =encoding utf-8 =head1 NAME Dancer::Config::Object - Access the config via methods instead of hashrefs =head1 DESCRIPTION If C<strict_config> is set to a true value in the configuration, the C<config()> subroutine will return an object instead of a hashref. Instead of this: my $serializer = config->{serializer}; my $username = config->{auth}{username}; You get this: my $serializer = config->serializer; my $username = config->auth->username; This helps to prevent typos. If you mistype a configuration name: my $pass = config->auth->pass; An exception will be thrown, tell you it can't find the method name, but listing available methods: Can't locate config attribute "pass". Available attributes: password, username If the hash key cannot be converted into a proper method name, you can still access it via a hash reference: my $some_value = config->{'99_bottles'}; And call methods on it, if possible: my $sadness = config->{'99_more_bottles'}->last_bottle; Hash keys pointing to hash references will in turn have those "objectified". Arrays will still be returned as array references. However, hashrefs inside of the array refs may still have their keys allowed as methods: my $some_value = config->some_list->[1]->host; =head1 METHOD NAME DEFINITION We use the following regular expression to determine if a hash key qualifies as a method: /^[[:alpha:]_][[:word:]]*$/; Note that this means C<naïve> (note the dots over the i) can be a method name, but unless you C<use utf8;> to declare that your source code is UTF-8, you may have disappointing results calling C<< config->naïve >>. Further, depending on your version of Perl and the software to read your config file ... well, you get the idea. We recommend sticking with ASCII identifiers if you wish your code to be portable. Patches/suggestions welcome. =head1 AUTHOR This module has been written by Alexis Sukrieh <sukria@cpan.org> and others, see the AUTHORS file that comes with this distribution for details. =head1 LICENSE This module is free software and is released under the same terms as Perl itself. =head1 SEE ALSO L<Dancer> and L<Dancer::Config>. =cut