package Catalyst::Component;
-use strict;
-use base qw/Class::Accessor::Fast Class::Data::Inheritable/;
-use NEXT;
+use Moose;
+use Class::MOP;
+use Class::MOP::Object;
+use Catalyst::Utils;
+use Class::C3::Adopt::NEXT;
+use Devel::InnerPackage ();
+use MRO::Compat;
+use mro 'c3';
+use Scalar::Util 'blessed';
+use Class::Load 'is_class_loaded';
+use Moose::Util 'find_meta';
+use namespace::clean -except => 'meta';
+
+with 'MooseX::Emulate::Class::Accessor::Fast';
+with 'Catalyst::ClassData';
-__PACKAGE__->mk_classdata($_) for qw/_config _plugins/;
=head1 NAME
__PACKAGE__->config( foo => 'bar' );
+ has foo => (
+ is => 'ro',
+ );
+
sub test {
my $self = shift;
- return $self->{foo};
+ return $self->foo;
}
sub forward_to_me {
my ( $self, $c ) = @_;
- $c->response->output( $self->{foo} );
+ $c->response->output( $self->foo );
}
-
+
1;
# Methods can be a request step
# Or just methods
print $c->comp('MyApp::Model::Something')->test;
- print $c->comp('MyApp::Model::Something')->{foo};
+ print $c->comp('MyApp::Model::Something')->foo;
=head1 DESCRIPTION
This is the universal base class for Catalyst components
(Model/View/Controller).
-It provides you with a generic new() for instantiation through Catalyst's
+It provides you with a generic new() for component construction through Catalyst's
component loader with config() support and a process() method placeholder.
-=head1 METHODS
-
-=head2 new($c)
+B<Note> that calling C<< $self->config >> inside a component is strongly
+not recommended - the correctly merged config should have already been
+passed to the constructor and stored in attributes - accessing
+the config accessor directly from an instance is likely to get the
+wrong values (as it only holds the class wide config, not things loaded
+from the config file!)
=cut
-sub new {
- my ( $self, $c ) = @_;
-
- # Temporary fix, some components does not pass context to constructor
- my $arguments = ( ref( $_[-1] ) eq 'HASH' ) ? $_[-1] : {};
+__PACKAGE__->mk_classdata('_plugins');
+__PACKAGE__->mk_classdata('_config');
+
+has catalyst_component_name => ( is => 'ro' ); # Cannot be required => 1 as context
+ # class @ISA component - HATE
+# Make accessor callable as a class method, as we need to call setup_actions
+# on the application class, which we don't have an instance of, ewwwww
+# Also, naughty modules like Catalyst::View::JSON try to write to _everything_,
+# so spit a warning, ignore that (and try to do the right thing anyway) here..
+around catalyst_component_name => sub {
+ my ($orig, $self) = (shift, shift);
+ Carp::cluck("Tried to write to the catalyst_component_name accessor - is your component broken or just mad? (Write ignored - using default value.)") if scalar @_;
+ blessed($self) ? $self->$orig() || blessed($self) : $self;
+};
+
+sub BUILDARGS {
+ my $class = shift;
+ my $args = {};
+
+ if (@_ == 1) {
+ $args = $_[0] if ref($_[0]) eq 'HASH';
+ } elsif (@_ == 2) { # is it ($app, $args) or foo => 'bar' ?
+ if (blessed($_[0])) {
+ $args = $_[1] if ref($_[1]) eq 'HASH';
+ } elsif (is_class_loaded($_[0]) &&
+ $_[0]->isa('Catalyst') && ref($_[1]) eq 'HASH') {
+ $args = $_[1];
+ } else {
+ $args = +{ @_ };
+ }
+ } elsif (@_ % 2 == 0) {
+ $args = +{ @_ };
+ }
- return $self->NEXT::new( { %{ $self->config }, %{$arguments} } );
+ return $class->merge_config_hashes( $class->config, $args );
}
-=head2 COMPONENT($c)
-
-=cut
-
sub COMPONENT {
- my ( $self, $c ) = @_;
+ my ( $class, $c ) = @_;
# Temporary fix, some components does not pass context to constructor
my $arguments = ( ref( $_[-1] ) eq 'HASH' ) ? $_[-1] : {};
-
- if ( my $new = $self->NEXT::COMPONENT( $c, $arguments ) ) {
- return $new;
+ if ( my $next = $class->next::can ) {
+ my ($next_package) = Class::MOP::get_code_info($next);
+ warn "There is a COMPONENT method resolving after Catalyst::Component in ${next_package}.\n";
+ warn "This behavior can no longer be supported, and so your application is probably broken.\n";
+ warn "Your linearized isa hierarchy is: " . join(', ', @{ mro::get_linear_isa($class) }) . "\n";
+ warn "Please see perldoc Catalyst::Upgrading for more information about this issue.\n";
}
- else {
- if ( my $new = $self->new( $c, $arguments ) ) {
- return $new;
- }
- else {
- my $class = ref $self || $self;
- my $new = { %{ $self->config }, %{$arguments} };
- return bless $new, $class;
+ return $class->new($c, $arguments);
+}
+
+sub config {
+ my $self = shift;
+ # Uncomment once sane to do so
+ #Carp::cluck("config method called on instance") if ref $self;
+ my $config = $self->_config || {};
+ if (@_) {
+ my $newconfig = { %{@_ > 1 ? {@_} : $_[0]} };
+ $self->_config(
+ $self->merge_config_hashes( $config, $newconfig )
+ );
+ } else {
+ # this is a bit of a kludge, required to make
+ # __PACKAGE__->config->{foo} = 'bar';
+ # work in a subclass.
+ # TODO maybe this should be a ClassData option?
+ my $class = blessed($self) || $self;
+ my $meta = find_meta($class);
+ unless (${ $meta->get_or_add_package_symbol('$_config') }) {
+ # Call merge_hashes to ensure we deep copy the parent
+ # config onto the subclass
+ $self->_config( Catalyst::Utils::merge_hashes($config, {}) );
}
}
+ return $self->_config;
}
-# remember to leave blank lines between the consecutive =head2's
-# otherwise the pod tools don't recognize the subsequent =head2s
+sub merge_config_hashes {
+ my ( $self, $lefthash, $righthash ) = @_;
+
+ return Catalyst::Utils::merge_hashes( $lefthash, $righthash );
+}
+
+sub process {
+
+ Catalyst::Exception->throw( message => ( ref $_[0] || $_[0] )
+ . " did not override Catalyst::Component::process" );
+}
+
+sub expand_modules {
+ my ($class, $component) = @_;
+ return Devel::InnerPackage::list_packages( $component );
+}
+
+__PACKAGE__->meta->make_immutable;
+
+1;
+
+__END__
+
+=head1 METHODS
+
+=head2 new($app, $arguments)
+
+Called by COMPONENT to instantiate the component; should return an object
+to be stored in the application's component hash.
+
+=head2 COMPONENT
+
+C<< my $component_instance = $component->COMPONENT($app, $arguments); >>
+
+If this method is present (as it is on all Catalyst::Component subclasses),
+it is called by Catalyst during setup_components with the application class
+as $app and any config entry on the application for this component (for example,
+in the case of MyApp::Controller::Foo this would be
+C<< MyApp->config('Controller::Foo' => \%conf >>).
+
+The arguments are expected to be a hashref and are merged with the
+C<< __PACKAGE__->config >> hashref before calling C<< ->new >>
+to instantiate the component.
+
+You can override it in your components to do custom construction, using
+something like this:
+
+ sub COMPONENT {
+ my ($class, $app, $args) = @_;
+ $args = $class->merge_config_hashes($class->config, $args);
+ return $class->new($app, $args);
+ }
+
+B<NOTE:> Generally when L<Catalyst> starts, it initializes all the components
+and passes the hashref present in any configutation information to the
+COMPONET method. For example
+
+ MyApp->config(
+ 'Model::Foo' => {
+ bar => 'baz',
+ });
+
+You would expect COMPONENT to be called like this ->COMPONENT( 'MyApp', +{ bar=>'baz'});
+
+This would happen ONCE during setup.
=head2 $c->config
=head2 $c->config($key, $value, ...)
-=cut
+Accessor for this component's config hash. Config values can be set as
+key value pair, or you can specify a hashref. In either case the keys
+will be merged with any existing config settings. Each component in
+a Catalyst application has its own config hash.
-sub config {
- my $self = shift;
- my $config = $self->_config;
- unless ($config) {
- $self->_config( $config = {} );
- }
- if (@_) {
- $config = { %{$config}, %{@_ > 1 ? {@_} : $_[0]} };
- $self->_config($config);
- }
- return $config;
-}
+The component's config hash is merged with any config entry on the
+application for this component and passed to C<new()> (as mentioned
+above at L</COMPONENT>). The recommended practice to access the merged
+config is to use a Moose attribute for each config entry on the
+receiving component.
=head2 $c->process()
+This is the default method called on a Catalyst component in the dispatcher.
+For instance, Views implement this action to render the response body
+when you forward to them. The default is an abstract method.
+
+=head2 $c->merge_config_hashes( $hashref, $hashref )
+
+Merges two hashes together recursively, giving right-hand precedence.
+Alias for the method in L<Catalyst::Utils>.
+
+=head2 $c->expand_modules( $setup_component_config )
+
+Return a list of extra components that this component has created. By default,
+it just looks for a list of inner packages of this component
+
=cut
-sub process {
+=head1 OPTIONAL METHODS
- Catalyst::Exception->throw( message => ( ref $_[0] || $_[0] )
- . " did not override Catalyst::Component::process" );
-}
+=head2 ACCEPT_CONTEXT($c, @args)
+
+Catalyst components are normally initialized during server startup, either
+as a Class or a Instance. However, some components require information about
+the current request. To do so, they can implement an ACCEPT_CONTEXT method.
+
+If this method is present, it is called during $c->comp/controller/model/view
+with the current $c and any additional args (e.g. $c->model('Foo', qw/bar baz/)
+would cause your MyApp::Model::Foo instance's ACCEPT_CONTEXT to be called with
+($c, 'bar', 'baz')) and the return value of this method is returned to the
+calling code in the application rather than the component itself.
+
+B<NOTE:> All classes that are L<Catalyst::Component>s will have a COMPONENT
+method, but classes that are intended to be factories or generators will
+have ACCEPT_CONTEXT. If you have initialization arguments (such as from
+configuration) that you wish to expose to the ACCEPT_CONTEXT you should
+proxy them in the factory instance. For example:
+
+ MyApp::Model::FooFactory;
+
+ use Moose;
+ extends 'Catalyst::Model';
+
+ has type => (is=>'ro', required=>1);
+
+ sub ACCEPT_CONTEXT {
+ my ($self, $c, @args) = @_;
+ return bless { args=>\@args }, $self->type;
+ }
+
+ MyApp::Model::Foo->meta->make_immutable;
+ MyApp::Model::Foo->config( type => 'Type1' );
+
+And in a controller:
+
+ my $type = $c->model('FooFactory', 1,2,3,4): # $type->isa('Type1')
=head1 SEE ALSO
L<Catalyst>, L<Catalyst::Model>, L<Catalyst::View>, L<Catalyst::Controller>.
-=head1 AUTHOR
+=head1 AUTHORS
-Sebastian Riedel, C<sri@cpan.org>
-Marcus Ramberg, C<mramberg@cpan.org>
-Matt S Trout, C<mst@shadowcatsystems.co.uk>
+Catalyst Contributors, see Catalyst.pm
=head1 COPYRIGHT
-This program is free software, you can redistribute it and/or modify it under
+This library is free software. You can redistribute it and/or modify it under
the same terms as Perl itself.
=cut
-
-1;