| Dancer documentation | Contained in the Dancer distribution. |
Dancer::Plugin - helper for writing Dancer plugins
Create plugins for Dancer
package Dancer::Plugin::LinkBlocker;
use Dancer ':syntax';
use Dancer::Plugin;
register block_links_from => sub {
my $conf = plugin_setting();
my $re = join ('|', @{$conf->{hosts}});
before sub {
if (request->referer && request->referer =~ /$re/) {
status 403 || $conf->{http_code};
}
};
};
register_plugin;
1;
And in your application:
package My::Webapp;
use Dancer ':syntax';
use Dancer::Plugin::LinkBlocker;
block_links_from; # this is exported by the plugin
You can extend Dancer by writing your own Plugin.
A plugin is a module that exports a bunch of symbols to the current namespace
(the caller will see all the symbols defined via register).
Note that you have to use the plugin wherever you want to use its symbols.
For instance, if you have Webapp::App1 and Webapp::App2, both loaded from your
main application, they both need to use FooPlugin if they want to use the
symbols exported by FooPlugin.
Lets you define a keyword that will be exported by the plugin.
register my_symbol_to_export => sub {
# ... some code
};
A Dancer plugin must end with this statement. This lets the plugin register all
the symbols define with register as exported symbols (via the Exporter
module).
A Dancer plugin inherits from Dancer::Plugin and Exporter transparently.
Configuration for plugin should be structured like this in the config.yaml of the application:
plugins:
plugin_name:
key: value
If plugin_setting is called inside a plugin, the appropriate configuration will be returned. The plugin_name should be the name of the package, or, if the plugin name is under the Dancer::Plugin:: namespace, the remaining part of the plugin name. Enclose the remaining part in quotes if it contains ::, e.g. for Dancer::Plugin::Foo::Bar, use:
plugins:
"Foo::Bar":
key: value
This module has been written by Alexis Sukrieh and others.
This module is free software and is published under the same terms as Perl itself.
| Dancer documentation | Contained in the Dancer distribution. |
package Dancer::Plugin; use strict; use warnings; use Carp; use base 'Exporter'; use Dancer::Config 'setting'; use Dancer::Hook; use base 'Exporter'; use vars qw(@EXPORT); @EXPORT = qw( add_hook register register_plugin plugin_setting ); sub register($&); my $_keywords = {}; sub add_hook { Dancer::Hook->new(@_) } sub plugin_setting { my $plugin_orig_name = caller(); (my $plugin_name = $plugin_orig_name) =~ s/Dancer::Plugin:://; return setting('plugins')->{$plugin_name} ||= {}; } sub register($&) { my ($keyword, $code) = @_; my $plugin_name = caller(); $keyword =~ /^[a-zA-Z_]+[a-zA-Z0-9_]*$/ or croak "You can't use '$keyword', it is an invalid name (it should match ^[a-zA-Z_]+[a-zA-Z0-9_]*$ )"; if (grep { $_ eq $keyword } map { s/^(?:\$|%|&|@|\*)//; $_ } (@Dancer::EXPORT, @Dancer::EXPORT_OK)) { croak "You can't use '$keyword', this is a reserved keyword"; } while (my ($plugin, $keywords) = each %$_keywords) { if (grep { $_->[0] eq $keyword } @$keywords) { croak "You can't use $keyword, this is a keyword reserved by $plugin"; } } $_keywords->{$plugin_name} ||= []; push @{$_keywords->{$plugin_name}}, [$keyword => $code]; } sub register_plugin { my ($application) = shift || caller(1); my ($plugin) = caller(); my @symbols = set_plugin_symbols($plugin); { no strict 'refs'; # tried to use unshift, but it yields an undef warning on $plugin (perl v5.12.1) @{"${plugin}::ISA"} = ('Exporter', 'Dancer::Plugin', @{"${plugin}::ISA"}); push @{"${plugin}::EXPORT"}, @symbols; } return 1; } sub set_plugin_symbols { my ($plugin) = @_; for my $keyword (@{$_keywords->{$plugin}}) { my ($name, $code) = @$keyword; { no strict 'refs'; *{"${plugin}::${name}"} = $code; } } return map { $_->[0] } @{$_keywords->{$plugin}}; } 1; __END__