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';
__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;
# 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.
+B<Note> that calling C<< $self->config >> inside a component is strongly
+not recommended - the correctly merged config should have already been
+passed to the constructor and stored in attributes - accessing
+the config accessor directly from an instance is likely to get the
+wrong values (as it only holds the class wide config, not things loaded
+from the config file!)
+
=cut
__PACKAGE__->mk_classdata('_plugins');
} elsif (@_ == 2) { # is it ($app, $args) or foo => 'bar' ?
if (blessed($_[0])) {
$args = $_[1] if ref($_[1]) eq 'HASH';
- } elsif (Class::MOP::is_class_loaded($_[0]) &&
+ } elsif (is_class_loaded($_[0]) &&
$_[0]->isa('Catalyst') && ref($_[1]) eq 'HASH') {
$args = $_[1];
- } elsif ($_[0] eq $_[1]) {
- $args = $_[1];
} else {
$args = +{ @_ };
}
# work in a subclass.
# TODO maybe this should be a ClassData option?
my $class = blessed($self) || $self;
- my $meta = Class::MOP::get_metaclass_by_name($class);
- unless ($meta->has_package_symbol('$_config')) {
+ 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, {}) );
C<< my $component_instance = $component->COMPONENT($app, $arguments); >>
-If this method is present (as it is on all Catalyst::Component subclasses,
+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 $app and any config entry on the application for this component (for example,
in the case of MyApp::Controller::Foo this would be
C<< __PACKAGE__->config >> hashref before calling C<< ->new >>
to instantiate the component.
-You can override it in your components to do custom instantiation, using
+You can override it in your components to do custom construction, using
something like this:
sub COMPONENT {
my ($class, $app, $args) = @_;
- $args = $self->merge_config_hashes($self->config, $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 configuration information to the
+COMPONENT 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 $c->config($hashref)
will be merged with any existing config settings. Each component in
a Catalyst application has its own config hash.
+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 $c->process()
This is the default method called on a Catalyst component in the dispatcher.
($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')
+
+B<NOTE:> If you define a ACCEPT_CONTEXT method it MUST check to see if the
+second argument is blessed (is a context) or not (is an application class name) and
+it MUST return something valid for the case when the scope is application. This is
+required because a component maybe be called from the application scope even if it
+requires a context and you must prevent errors from being issued if this happens.
+Remember not all components that ACCEPT_CONTEXT actually need or use context information
+(and there is a school of thought that suggestions doing so is a design error anyway...)
+
=head1 SEE ALSO
L<Catalyst>, L<Catalyst::Model>, L<Catalyst::View>, L<Catalyst::Controller>.