package Catalyst::IOC::Container;
-use Bread::Board;
+use Bread::Board qw/depends_on/;
use Moose;
use Config::Any;
use Data::Visitor::Callback;
use Catalyst::Utils ();
+use List::Util qw(first);
+use Devel::InnerPackage ();
+use Hash::Util qw/lock_hash/;
use MooseX::Types::LoadableClass qw/ LoadableClass /;
+use Moose::Util;
+use Scalar::Util qw/refaddr/;
use Catalyst::IOC::BlockInjection;
+use Catalyst::IOC::ConstructorInjection;
+use Module::Pluggable::Object ();
use namespace::autoclean;
extends 'Bread::Board::Container';
default => sub { +{} },
);
-has name => (
- is => 'ro',
- isa => 'Str',
- default => 'TestApp',
-);
-
has sub_container_class => (
isa => LoadableClass,
is => 'ro',
);
sub BUILD {
- my $self = shift;
+ my ( $self, $params ) = @_;
$self->add_service(
$self->${\"build_${_}_service"}
substitutions
file
driver
- name
+ catalyst_application
prefix
extensions
path
local_files
global_config
local_config
+ class_config
config_local_suffix
config_path
+ locate_components
+ home
+ root_dir
/;
+ my $config = $self->resolve( service => 'config' );
+
+ # don't force default_component to be undef if the config wasn't set
+ my @default_view = $config->{default_view}
+ ? ( default_component => $config->{default_view} )
+ : ( )
+ ;
+ my @default_model = $config->{default_model}
+ ? ( default_component => $config->{default_model} )
+ : ( )
+ ;
+
$self->add_sub_container(
- $self->${ \"build_${_}_subcontainer" }
- ) for qw/ model view controller /;
+ $self->build_component_subcontainer
+ );
+
+ $self->add_sub_container(
+ $self->build_controller_subcontainer
+ );
+
+ $self->add_sub_container(
+ $self->build_view_subcontainer( @default_view )
+ );
+
+ $self->add_sub_container(
+ $self->build_model_subcontainer( @default_model )
+ );
+
+ {
+ no strict 'refs';
+ no warnings 'once';
+ my $class = ref $self;
+ ${ $class . '::customise_container' }->($self)
+ if ${ $class . '::customise_container' };
+ }
}
sub build_model_subcontainer {
my $self = shift;
- return $self->new_sub_container(
+ return $self->new_sub_container( @_,
name => 'model',
);
}
sub build_view_subcontainer {
my $self = shift;
- return $self->new_sub_container(
+ return $self->new_sub_container( @_,
name => 'view',
);
}
);
}
-sub build_name_service {
+sub build_component_subcontainer {
+ my $self = shift;
+
+ return Bread::Board::Container->new(
+ name => 'component',
+ );
+}
+
+sub build_home_service {
+ my $self = shift;
+
+ return Bread::Board::BlockInjection->new(
+ lifecycle => 'Singleton',
+ name => 'home',
+ block => sub {
+ my $self = shift;
+ my $class = $self->param('catalyst_application');
+
+ if ( my $env = Catalyst::Utils::env_value( $class, 'HOME' ) ) {
+ return $env;
+ }
+
+ if ( my $home = $self->param('home_flag') ) {
+ return $home;
+ }
+
+ return Catalyst::Utils::home($class);
+ },
+ parameters => {
+ home_flag => { is => 'ro', isa => 'Str|Undef', required => 0 }
+ },
+ dependencies => [ depends_on('catalyst_application') ],
+ );
+}
+
+sub build_root_dir_service {
my $self = shift;
- return Bread::Board::Literal->new( name => 'name', value => $self->name );
+ return Bread::Board::BlockInjection->new(
+ lifecycle => 'Singleton',
+ name => 'root_dir',
+ block => sub {
+ my $self = shift;
+
+ return Path::Class::Dir->new( $self->param('home') )->subdir('root');
+ },
+ dependencies => [ depends_on('home') ],
+ );
+}
+
+sub build_catalyst_application_service {
+ my $self = shift;
+
+ return Bread::Board::Literal->new( name => 'catalyst_application', value => $self->name );
}
sub build_driver_service {
my $self = shift;
return Bread::Board::BlockInjection->new(
+ lifecycle => 'Singleton',
name => 'extensions',
block => sub {
return \@{Config::Any->extensions};
my $self = shift;
return Bread::Board::BlockInjection->new(
+ lifecycle => 'Singleton',
name => 'prefix',
block => sub {
- return Catalyst::Utils::appprefix( shift->param('name') );
+ return Catalyst::Utils::appprefix( shift->param('catalyst_application') );
},
- dependencies => [ depends_on('name') ],
+ dependencies => [ depends_on('catalyst_application') ],
);
}
my $self = shift;
return Bread::Board::BlockInjection->new(
+ lifecycle => 'Singleton',
name => 'path',
block => sub {
my $s = shift;
- return Catalyst::Utils::env_value( $s->param('name'), 'CONFIG' )
+ return Catalyst::Utils::env_value( $s->param('catalyst_application'), 'CONFIG' )
|| $s->param('file')
- || $s->param('name')->path_to( $s->param('prefix') );
+ || $s->param('catalyst_application')->path_to( $s->param('prefix') );
},
- dependencies => [ depends_on('file'), depends_on('name'), depends_on('prefix') ],
+ dependencies => [ depends_on('file'), depends_on('catalyst_application'), depends_on('prefix') ],
);
}
my $self = shift;
return Bread::Board::BlockInjection->new(
+ lifecycle => 'Singleton',
name => 'config',
block => sub {
my $s = shift;
my $v = Data::Visitor::Callback->new(
plain_value => sub {
return unless defined $_;
- return $self->_config_substitutions( $s->param('name'), $s->param('substitutions'), $_ );
+ return $self->_config_substitutions( $s->param('catalyst_application'), $s->param('substitutions'), $_ );
}
);
$v->visit( $s->param('raw_config') );
},
- dependencies => [ depends_on('name'), depends_on('raw_config'), depends_on('substitutions') ],
+ dependencies => [ depends_on('catalyst_application'), depends_on('raw_config'), depends_on('substitutions') ],
);
}
my $self = shift;
return Bread::Board::BlockInjection->new(
+ lifecycle => 'Singleton',
name => 'raw_config',
block => sub {
my $s = shift;
my @global = @{$s->param('global_config')};
my @locals = @{$s->param('local_config')};
- my $config = {};
+ my $config = $s->param('class_config');
+
for my $cfg (@global, @locals) {
for (keys %$cfg) {
$config = Catalyst::Utils::merge_hashes( $config, $cfg->{$_} );
}
}
+
return $config;
},
- dependencies => [ depends_on('global_config'), depends_on('local_config') ],
+ dependencies => [ depends_on('global_config'), depends_on('local_config'), depends_on('class_config') ],
);
}
my $self = shift;
return Bread::Board::BlockInjection->new(
+ lifecycle => 'Singleton',
name => 'global_files',
block => sub {
my $s = shift;
my $self = shift;
return Bread::Board::BlockInjection->new(
+ lifecycle => 'Singleton',
name => 'local_files',
block => sub {
my $s = shift;
);
}
+sub build_class_config_service {
+ my $self = shift;
+
+ return Bread::Board::BlockInjection->new(
+ lifecycle => 'Singleton',
+ name => 'class_config',
+ block => sub {
+ my $s = shift;
+ my $app = $s->param('catalyst_application');
+
+ # Container might be called outside Catalyst context
+ return {} unless Class::MOP::is_class_loaded($app);
+
+ # config might not have been defined
+ return $app->config || {};
+ },
+ dependencies => [ depends_on('catalyst_application') ],
+ );
+}
+
sub build_global_config_service {
my $self = shift;
return Bread::Board::BlockInjection->new(
+ lifecycle => 'Singleton',
name => 'global_config',
block => sub {
my $s = shift;
my $self = shift;
return Bread::Board::BlockInjection->new(
+ lifecycle => 'Singleton',
name => 'local_config',
block => sub {
my $s = shift;
my $self = shift;
return Bread::Board::BlockInjection->new(
+ lifecycle => 'Singleton',
name => 'config_path',
block => sub {
my $s = shift;
my $self = shift;
return Bread::Board::BlockInjection->new(
+ lifecycle => 'Singleton',
name => 'config_local_suffix',
block => sub {
my $s = shift;
- my $suffix = Catalyst::Utils::env_value( $s->param('name'), 'CONFIG_LOCAL_SUFFIX' ) || $self->config_local_suffix;
+ my $suffix = Catalyst::Utils::env_value( $s->param('catalyst_application'), 'CONFIG_LOCAL_SUFFIX' ) || $self->config_local_suffix;
return $suffix;
},
- dependencies => [ depends_on('name') ],
+ dependencies => [ depends_on('catalyst_application') ],
);
}
+sub build_locate_components_service {
+ my $self = shift;
+
+ return Bread::Board::BlockInjection->new(
+ lifecycle => 'Singleton',
+ name => 'locate_components',
+ block => sub {
+ my $s = shift;
+ my $class = $s->param('catalyst_application');
+ my $config = $s->param('config')->{ setup_components };
+
+ Catalyst::Exception->throw(
+ qq{You are using search_extra config option. That option is\n} .
+ qq{deprecated, please refer to the documentation for\n} .
+ qq{other ways of achieving the same results.\n}
+ ) if delete $config->{ search_extra };
+
+ my @paths = qw( ::Controller ::C ::Model ::M ::View ::V );
+
+ my $locator = Module::Pluggable::Object->new(
+ search_path => [ map { s/^(?=::)/$class/; $_; } @paths ],
+ %$config
+ );
+
+ return [ $locator->plugins ];
+ },
+ dependencies => [ depends_on('catalyst_application'), depends_on('config') ],
+ );
+}
+
+sub setup_components {
+ my $self = shift;
+ my $class = $self->resolve( service => 'catalyst_application' );
+ my @comps = @{ $self->resolve( service => 'locate_components' ) };
+ my %comps = map { $_ => 1 } @comps;
+ my $deprecatedcatalyst_component_names = 0;
+
+ my $app_locate_components_addr = refaddr(
+ $class->can('locate_components')
+ );
+ my $cat_locate_components_addr = refaddr(
+ Catalyst->can('locate_components')
+ );
+
+ if ($app_locate_components_addr != $cat_locate_components_addr) {
+ # FIXME - why not just say: @comps = $class->locate_components() ?
+ $class->log->warn(qq{You have overridden locate_components. That } .
+ qq{no longer works. Please refer to the documentation to achieve } .
+ qq{similar results.\n}
+ );
+ }
+
+ for my $component ( @comps ) {
+
+ # We pass ignore_loaded here so that overlay files for (e.g.)
+ # Model::DBI::Schema sub-classes are loaded - if it's in @comps
+ # we know M::P::O found a file on disk so this is safe
+
+ Catalyst::Utils::ensure_class_loaded( $component, { ignore_loaded => 1 } );
+ }
+
+ for my $component (@comps) {
+ $self->add_component( $component );
+ # FIXME - $instance->expand_modules() is broken
+ my @expanded_components = $self->expand_component_module( $component );
+
+ if (
+ !$deprecatedcatalyst_component_names &&
+ ($deprecatedcatalyst_component_names = $component =~ m/::[CMV]::/) ||
+ ($deprecatedcatalyst_component_names = grep { /::[CMV]::/ } @expanded_components)
+ ) {
+ # FIXME - should I be calling warn here?
+ # Maybe it's time to remove it, or become fatal
+ $class->log->warn(qq{Your application is using the deprecated ::[MVC]:: type naming scheme.\n}.
+ qq{Please switch your class names to ::Model::, ::View:: and ::Controller: as appropriate.\n}
+ );
+ }
+
+ for my $component (@expanded_components) {
+ $self->add_component( $component )
+ unless $comps{$component};
+ }
+ }
+}
+
sub _fix_syntax {
my $config = shift;
my @components = (
my $sub_container = $self->get_sub_container( $sub_container_name );
+ if (!$name) {
+ my $default = $sub_container->default_component;
+
+ return $sub_container->get_component( $default, $c, @args )
+ if $default && $sub_container->has_service( $default );
+
+ # FIXME - should I be calling $c->log->warn here?
+ # this is never a controller, so this is safe
+ $c->log->warn( "Calling \$c->$sub_container_name() is not supported unless you specify one of:" );
+ $c->log->warn( "* \$c->config(default_$sub_container_name => 'the name of the default $sub_container_name to use')" );
+ $c->log->warn( "* \$c->stash->{current_$sub_container_name} # the name of the view to use for this request" );
+ $c->log->warn( "* \$c->stash->{current_${sub_container_name}_instance} # the instance of the $sub_container_name to use for this request" );
+
+ return;
+ }
+
return $sub_container->get_component_regexp( $name, $c, @args )
if ref $name;
return;
}
+sub find_component {
+ my ( $self, $component, @args ) = @_;
+ my ( $type, $name ) = _get_component_type_name($component);
+ my @result;
+
+ return $self->get_component_from_sub_container(
+ $type, $name, @args
+ ) if $type;
+
+ my $query = ref $component
+ ? $component
+ : qr{^$component$}
+ ;
+
+ for my $subcontainer_name (qw/model view controller/) {
+ my $subcontainer = $self->get_sub_container( $subcontainer_name );
+ my @components = $subcontainer->get_service_list;
+ @result = grep { m{$component} } @components;
+
+ return map { $subcontainer->get_component( $_, @args ) } @result
+ if @result;
+ }
+
+ # one last search for things like $c->comp(qr/::M::/)
+ @result = $self->_find_component_regexp(
+ $component, @args
+ ) if !@result and ref $component;
+
+ # it expects an empty list on failed searches
+ return @result;
+}
+
+sub _find_component_regexp {
+ my ( $self, $component, $ctx, @args ) = @_;
+ my @result;
+
+ my @components = grep { m{$component} } keys %{ $self->get_all_components($ctx) };
+
+ for (@components) {
+ my ($type, $name) = _get_component_type_name($_);
+
+ push @result, $self->get_component_from_sub_container(
+ $type, $name, $ctx, @args
+ ) if $type;
+ }
+
+ return @result;
+}
+
+# FIXME
+# what exactly should this method return?
+# By default, for back-compatibility, we have two services for each component:
+# - one in the model|view|controller sub-container
+# - and another in the component sub-container
+# the latter is a Singleton, it executes the COMPONENT method, and the first
+# is executed at every call, executing ACCEPT_CONTEXT. It's just a layer.
+#
+# So the one in $type sub-container is pretty useless by default. But when the
+# user overrides the container (which is what we want), the sub-container they
+# will use is precisely $type, not 'component'. So for now, I'm returning both
+# services, to decide later what to do.
+sub get_all_component_services {
+ my $self = shift;
+
+ my %components;
+ my $components_container = $self->get_sub_container('component');
+
+ foreach my $type (qw/model view controller /) {
+ my $container = $self->get_sub_container($type);
+
+ for my $component ($container->get_service_list) {
+ my $comp_service = $container->get_service($component);
+
+ my $key = $comp_service->catalyst_component_name;
+ my %values = (
+ type => $type,
+ service => $comp_service,
+ );
+
+ my $comp_name = "${type}_${component}";
+ if ($components_container->has_service($comp_name)) {
+ $values{backcompat_service} = $components_container->get_service($comp_name);
+ }
+
+ $components{$key} = \%values;
+ }
+ }
+
+ return lock_hash %components;
+}
+
+sub get_all_singleton_lifecycle_components {
+ my $self = shift;
+
+ my %components;
+ my $components_container = $self->get_sub_container('component');
+
+ foreach my $type (qw/model view controller /) {
+ my $container = $self->get_sub_container($type);
+
+ for my $component ($container->get_service_list) {
+ my $comp_service = $container->get_service($component);
+
+ my $key = $comp_service->catalyst_component_name;
+ my $lifecycle = $comp_service->lifecycle;
+ my $comp_name = "${type}_${component}";
+
+ if (defined $lifecycle && $lifecycle eq 'Singleton') {
+ $components{$key} = $comp_service->get;
+ }
+ elsif ($components_container->has_service($comp_name)) {
+ $components{$key} = $components_container->get_service($comp_name)->get;
+ }
+ }
+ }
+
+ return lock_hash %components;
+}
+
+sub get_all_components {
+ my ($self, $class) = @_;
+ my %components;
+
+ # FIXME - if we're getting from these containers, we need to either:
+ # - pass 'ctx' and 'accept_context_args' OR
+ # - make these params optional
+ # big problem when setting up the dispatcher - this method is called
+ # as $container->get_all_components('MyApp'). What to do with Request
+ # life cycles?
+ foreach my $type (qw/model view controller /) {
+ my $container = $self->get_sub_container($type);
+
+ for my $component ($container->get_service_list) {
+ my $comp_service = $container->get_service($component);
+
+ $components{$comp_service->catalyst_component_name} = $comp_service->get(ctx => $class);
+ }
+ }
+
+ return lock_hash %components;
+}
+
+sub add_component {
+ my ( $self, $component ) = @_;
+ my ( $type, $name ) = _get_component_type_name($component);
+
+ return unless $type;
+
+ # The 'component' sub-container will create the object, and store it's
+ # instance, which, by default, will live throughout the application.
+ # The model/view/controller sub-containers only reference the instance
+ # held in the aforementioned sub-container, and execute the ACCEPT_CONTEXT
+ # sub every time they are called, when it exists.
+ my $instance_container = $self->get_sub_container('component');
+ my $accept_context_container = $self->get_sub_container($type);
+
+ # Custom containers might have added the service already
+ # We don't want to override that
+ return if $accept_context_container->has_service( $name );
+
+ my $component_service_name = "${type}_${name}";
+
+ $instance_container->add_service(
+ Catalyst::IOC::ConstructorInjection->new(
+ name => $component_service_name,
+ catalyst_component_name => $component,
+ class => $component,
+ lifecycle => 'Singleton',
+ dependencies => [
+ depends_on( '/catalyst_application' ),
+ ],
+ ),
+ );
+ # XXX - FIXME - We have to explicitly build the service here,
+ # causing the COMPONENT method to be called early here, as otherwise
+ # if the component method defines other classes (e.g. the
+ # ACCEPT_CONTEXT injection Model::DBIC::Schema does)
+ # then they won't be found by Devel::InnerPackage
+ # see also t/aggregate/unit_core_component_loading.t
+ $instance_container->get_service($component_service_name)->get;
+
+ $accept_context_container->add_service(
+ Catalyst::IOC::BlockInjection->new(
+ name => $name,
+ catalyst_component_name => $component,
+ dependencies => [
+ depends_on( "/component/$component_service_name" ),
+ ],
+ block => sub { shift->param($component_service_name) },
+ )
+ );
+}
+
+# FIXME: should this sub exist?
+# should it be moved to Catalyst::Utils,
+# or replaced by something already existing there?
+sub _get_component_type_name {
+ my ( $component ) = @_;
+ my $result;
+
+ while ( !$result and (my $index = index $component, '::') > 0 ) {
+ my $type = lc substr $component, 0, $index;
+ $component = substr $component, $index + 2;
+ $result = first { $type eq $_ or $type eq substr($_, 0, 1) }
+ qw{ model view controller };
+ }
+
+ return ($result, $component);
+}
+
+sub expand_component_module {
+ my ( $class, $module ) = @_;
+ return Devel::InnerPackage::list_packages( $module );
+}
+
+__PACKAGE__->meta->make_immutable;
+
1;
__END__
Catalyst::Container - IOC for Catalyst components
+=head1 SYNOPSIS
+
+=head1 DESCRIPTION
+
=head1 METHODS
+=head1 Methods for Building Containers
+
+=head2 build_component_subcontainer
+
+Container that stores all components, i.e. all models, views and controllers
+together. Each service is an instance of the actual component, and by default
+it lives while the application is running. Retrieving components from this
+sub-container will instantiate the component, if it hasn't been instantiated
+already, but will not execute ACCEPT_CONTEXT.
+
=head2 build_model_subcontainer
+Container that stores references for all models that are inside the components
+sub-container. Retrieving a model triggers ACCEPT_CONTEXT, if it exists.
+
=head2 build_view_subcontainer
+Same as L<build_model_subcontainer>, but for views.
+
=head2 build_controller_subcontainer
-=head2 build_name_service
+Same as L<build_model_subcontainer>, but for controllers.
+
+=head1 Methods for Building Services
+
+=head2 build_catalyst_application_service
+
+Name of the application (such as MyApp).
+
+=head2 build_home_service
+
+The application home directory. All the files (including classes, scripts, etc)
+created for this application are in this directory, or in a sub-directory below
+this one.
+
+=head2 build_root_dir_service
+
+Inside the application home (as explained in L</build_home_service>), there is
+a root directory. This is where all templates and static files are.
=head2 build_driver_service
+Config options passed directly to the driver being used.
+
=head2 build_file_service
+?
+
=head2 build_substitutions_service
+This method substitutes macros found with calls to a function. There are a
+number of default macros:
+
+=over
+
+=item * C<__HOME__> - replaced with C<$c-E<gt>path_to('')>
+
+=item * C<__ENV(foo)__> - replaced with the value of C<$ENV{foo}>
+
+=item * C<__path_to(foo/bar)__> - replaced with C<$c-E<gt>path_to('foo/bar')>
+
+=item * C<__literal(__FOO__)__> - leaves __FOO__ alone (allows you to use
+C<__DATA__> as a config value, for example)
+
+=back
+
+The parameter list is split on comma (C<,>). You can override this method to
+do your own string munging, or you can define your own macros in
+C<< <MyApp->config( 'Plugin::ConfigLoader' => { substitutions => { ... } } ) >>.
+Example:
+
+ MyApp->config( 'Plugin::ConfigLoader' => {
+ substitutions => {
+ baz => sub { my $c = shift; qux( @_ ); },
+ },
+ });
+
+The above will respond to C<__baz(x,y)__> in config strings.
+
=head2 build_extensions_service
+Config::Any's available config file extensions (e.g. xml, json, pl, etc).
+
=head2 build_prefix_service
+The prefix, based on the application name, that will be used to look-up the
+config files (which will be in the format $prefix.$extension). If the app is
+MyApp::Foo, the prefix will be myapp_foo.
+
=head2 build_path_service
+The path to the config file (or environment variable, if defined).
+
=head2 build_config_service
+The resulting configuration for the application, after it has successfully
+been loaded, and all substitutions have been made.
+
=head2 build_raw_config_service
+The merge of local_config and global_config hashes, before substitutions.
+
=head2 build_global_files_service
+Gets all files for config that don't have the local_suffix, such as myapp.conf.
+
=head2 build_local_files_service
+Gets all files for config that have the local_suffix, such as myapp_local.conf.
+
=head2 build_global_config_service
+Reads config from global_files.
+
=head2 build_local_config_service
+Reads config from local_files.
+
+=head2 build_class_config_service
+
+Reads config set from the application's class attribute config,
+i.e. MyApp->config( name => 'MyApp', ... )
+
=head2 build_config_path_service
+Splits the path to the config file, and returns on array ref containing
+the path to the config file minus the extension in the first position,
+and the extension in the second.
+
=head2 build_config_local_suffix_service
-=head2 _fix_syntax
+Determines the suffix of files used to override the main config. By default
+this value is C<local>, which will load C<myapp_local.conf>. The suffix can
+be specified in the following order of preference:
+
+=over
+
+=item * C<$ENV{ MYAPP_CONFIG_LOCAL_SUFFIX }>
+
+=item * C<$ENV{ CATALYST_CONFIG_LOCAL_SUFFIX }>
+
+=back
+
+The first one of these values found replaces the default of C<local> in the
+name of the local config file to be loaded.
+
+For example, if C< $ENV{ MYAPP_CONFIG_LOCAL_SUFFIX }> is set to C<testing>,
+ConfigLoader will try and load C<myapp_testing.conf> instead of
+C<myapp_local.conf>.
+
+=head2 build_locate_components_service
+
+This method is meant to provide a list of component modules that should be
+setup for the application. By default, it will use L<Module::Pluggable>.
+
+Specify a C<setup_components> config option to pass additional options directly
+to L<Module::Pluggable>.
+
+=head1 Other methods
+
+=head2 get_component_from_sub_container($sub_container, $name, $c, @args)
+
+Looks for components in a given sub-container (such as controller, model or
+view), and returns the searched component. If $name is undef, it returns the
+default component (such as default_view, if $sub_container is 'view'). If
+$name is a regexp, it returns an array of matching components. Otherwise, it
+looks for the component with name $name.
+
+=head2 get_all_components
+
+Fetches all the components, in each of the sub_containers model, view and
+controller, and returns a read-only hash. The keys are the class names, and
+the values are the blessed objects. This is what is returned by $c->components.
+
+=head2 add_component
+
+Adds a component to the appropriate sub-container. The sub-container is guessed
+by the component name given.
+
+=head2 find_component
+
+Searches for components in all containers. If $component is the full class
+name, the sub-container is guessed, and it gets the searched component in there.
+Otherwise, it looks for a component with that name in all sub-containers. If
+$component is a regexp it calls _find_component_regexp and matches all
+components against that regexp.
+
+=head2 expand_component_module
+
+Components found by C<locate_components> will be passed to this method, which
+is expected to return a list of component (package) names to be set up.
+
+=head2 setup_components
-=head2 _config_substitutions
+Uses locate_components service to list the components, and adds them to the
+appropriate sub-containers, using add_component().
=head1 AUTHORS