X-Git-Url: http://git.shadowcat.co.uk/gitweb/gitweb.cgi?a=blobdiff_plain;f=lib%2FCatalyst.pm;h=891b7229b04c0ef9934d79cf8722869a4a1753c0;hb=136c3a0d6a7add94f0419f8a4c4aeac74070aeec;hp=92621a10eb151f117ccb27b4d0feb688645a3600;hpb=99e6803ef202f2af101c02f2d7d2abf47d620165;p=catagits%2FCatalyst-Runtime.git
diff --git a/lib/Catalyst.pm b/lib/Catalyst.pm
index 92621a1..891b722 100644
--- a/lib/Catalyst.pm
+++ b/lib/Catalyst.pm
@@ -63,7 +63,9 @@ has request => (
is => 'rw',
default => sub {
my $self = shift;
- $self->request_class->new($self->_build_request_constructor_args);
+ my $class = ref $self;
+ my $composed_request_class = $class->composed_request_class;
+ return $composed_request_class->new( $self->_build_request_constructor_args);
},
lazy => 1,
);
@@ -77,11 +79,30 @@ sub _build_request_constructor_args {
\%p;
}
+sub composed_request_class {
+ my $class = shift;
+ my @traits = (@{$class->request_class_traits||[]}, @{$class->config->{request_class_traits}||[]});
+
+ # For each trait listed, figure out what the namespace is. First we try the $trait
+ # as it is in the config. Then try $MyApp::TraitFor::Request:$trait. Last we try
+ # Catalyst::TraitFor::Request::$trait. If none load, throw error.
+
+ my $trait_ns = 'TraitFor::Request';
+ my @normalized_traits = map {
+ Class::Load::load_first_existing_class($_, $class.'::'.$trait_ns.'::'. $_, 'Catalyst::'.$trait_ns.'::'.$_)
+ } @traits;
+
+ return $class->_composed_request_class ||
+ $class->_composed_request_class(Moose::Util::with_traits($class->request_class, @normalized_traits));
+}
+
has response => (
is => 'rw',
default => sub {
my $self = shift;
- $self->response_class->new($self->_build_response_constructor_args);
+ my $class = ref $self;
+ my $composed_response_class = $class->composed_response_class;
+ return $composed_response_class->new( $self->_build_response_constructor_args);
},
lazy => 1,
);
@@ -92,6 +113,19 @@ sub _build_response_constructor_args {
};
}
+sub composed_response_class {
+ my $class = shift;
+ my @traits = (@{$class->response_class_traits||[]}, @{$class->config->{response_class_traits}||[]});
+
+ my $trait_ns = 'TraitFor::Response';
+ my @normalized_traits = map {
+ Class::Load::load_first_existing_class($_, $class.'::'.$trait_ns.'::'. $_, 'Catalyst::'.$trait_ns.'::'.$_)
+ } @traits;
+
+ return $class->_composed_response_class ||
+ $class->_composed_response_class(Moose::Util::with_traits($class->response_class, @normalized_traits));
+}
+
has namespace => (is => 'rw');
sub depth { scalar @{ shift->stack || [] }; }
@@ -114,22 +148,39 @@ our $RECURSION = 1000;
our $DETACH = Catalyst::Exception::Detach->new;
our $GO = Catalyst::Exception::Go->new;
-#I imagine that very few of these really need to be class variables. if any.
+#I imagine that very few of these really
+#need to be class variables. if any.
#maybe we should just make them attributes with a default?
__PACKAGE__->mk_classdata($_)
for qw/components arguments dispatcher engine log dispatcher_class
engine_loader context_class request_class response_class stats_class
setup_finished _psgi_app loading_psgi_file run_options _psgi_middleware
- _data_handlers _encoding _encode_check finalized_default_middleware/;
+ _data_handlers _encoding _encode_check finalized_default_middleware
+ request_class_traits response_class_traits stats_class_traits
+ _composed_request_class _composed_response_class _composed_stats_class/;
__PACKAGE__->dispatcher_class('Catalyst::Dispatcher');
__PACKAGE__->request_class('Catalyst::Request');
__PACKAGE__->response_class('Catalyst::Response');
__PACKAGE__->stats_class('Catalyst::Stats');
+
+sub composed_stats_class {
+ my $class = shift;
+ my @traits = (@{$class->stats_class_traits||[]}, @{$class->config->{stats_class_traits}||[]});
+
+ my $trait_ns = 'TraitFor::Stats';
+ my @normalized_traits = map {
+ Class::Load::load_first_existing_class($_, $class.'::'.$trait_ns.'::'. $_, 'Catalyst::'.$trait_ns.'::'.$_)
+ } @traits;
+
+ return $class->_composed_stats_class ||
+ $class->_composed_stats_class(Moose::Util::with_traits($class->stats_class, @normalized_traits));
+}
+
__PACKAGE__->_encode_check(Encode::FB_CROAK | Encode::LEAVE_SRC);
# Remember to update this in Catalyst::Runtime as well!
-our $VERSION = '5.90084';
+our $VERSION = '5.90094';
$VERSION = eval $VERSION if $VERSION =~ /_/; # numify for warning-free dev releases
sub import {
@@ -171,6 +222,11 @@ sub _application { $_[0] }
Catalyst - The Elegant MVC Web Application Framework
+=for html
+
+
+
=head1 SYNOPSIS
See the L distribution for comprehensive
@@ -514,6 +570,7 @@ t/middleware-stash.t in the distribution /t directory.
sub stash {
my $c = shift;
+ $c->log->error("You are requesting the stash but you don't have a context") unless blessed $c;
return Catalyst::Middleware::Stash::get_stash($c->req->env)->(@_);
}
@@ -583,22 +640,42 @@ sub has_errors { scalar(@{shift->error}) ? 1:0 }
=head2 $c->last_error
Returns the most recent error in the stack (the one most recently added...)
-or nothing if there are no errors.
+or nothing if there are no errors. This does not modify the contents of the
+error stack.
=cut
-sub last_error { my ($err, @errs) = @{shift->error}; return $err }
+sub last_error {
+ my (@errs) = @{shift->error};
+ return scalar(@errs) ? $errs[-1]: undef;
+}
=head2 shift_errors
-shifts the most recently added error off the error stack and returns if. Returns
+shifts the most recently added error off the error stack and returns it. Returns
nothing if there are no more errors.
=cut
sub shift_errors {
my ($self) = @_;
- my ($err, @errors) = @{$self->error};
+ my @errors = @{$self->error};
+ my $err = shift(@errors);
+ $self->{error} = \@errors;
+ return $err;
+}
+
+=head2 pop_errors
+
+pops the most recently added error off the error stack and returns it. Returns
+nothing if there are no more errors.
+
+=cut
+
+sub pop_errors {
+ my ($self) = @_;
+ my @errors = @{$self->error};
+ my $err = pop(@errors);
$self->{error} = \@errors;
return $err;
}
@@ -685,13 +762,20 @@ sub _comp_names {
}
# Filter a component before returning by calling ACCEPT_CONTEXT if available
+
sub _filter_component {
my ( $c, $comp, @args ) = @_;
+ if(ref $comp eq 'CODE') {
+ $comp = $comp->();
+ }
+
if ( eval { $comp->can('ACCEPT_CONTEXT'); } ) {
- return $comp->ACCEPT_CONTEXT( $c, @args );
+ return $comp->ACCEPT_CONTEXT( $c, @args );
}
+ $c->log->warn("You called component '${\$comp->catalyst_component_name}' with arguments [@args], but this component does not ACCEPT_CONTEXT, so args are ignored.") if scalar(@args) && $c->debug;
+
return $comp;
}
@@ -738,7 +822,8 @@ Gets a L instance by name.
$c->model('Foo')->do_stuff;
-Any extra arguments are directly passed to ACCEPT_CONTEXT.
+Any extra arguments are directly passed to ACCEPT_CONTEXT, if the model
+defines ACCEPT_CONTEXT. If it does not, the args are discarded.
If the name is omitted, it will look for
- a model object in $c->stash->{current_model_instance}, then
@@ -1342,6 +1427,7 @@ EOF
: $class->log->debug(q/Couldn't find home/);
my $column_width = Catalyst::Utils::term_width() - 8 - 9;
+
my $t = Text::SimpleTable->new( [ $column_width, 'Class' ], [ 8, 'Type' ] );
for my $comp ( sort keys %{ $class->components } ) {
my $type = ref $class->components->{$comp} ? 'instance' : 'class';
@@ -1447,6 +1533,10 @@ In general the scheme of the generated URI object will follow the incoming reque
however if your targeted action or action chain has the Scheme attribute it will
use that instead.
+Also, if the targeted Action or Action chain declares Args/CaptureArgs that have
+type constraints, we will require that your proposed URL verify on those declared
+constraints.
+
=cut
sub uri_for {
@@ -1465,60 +1555,59 @@ sub uri_for {
carp "uri_for called with undef argument" if grep { ! defined $_ } @args;
- my @encoded_args = ();
- foreach my $arg (@args) {
- if(ref($arg)||'' eq 'ARRAY') {
- push @encoded_args, [map {
- my $encoded = encode_utf8 $_;
- $encoded =~ s/([^$URI::uric])/$URI::Escape::escapes{$1}/go;
- $encoded;
- } @$arg];
- } else {
- push @encoded_args, do {
- my $encoded = encode_utf8 $arg;
- $encoded =~ s/([^$URI::uric])/$URI::Escape::escapes{$1}/go;
- $encoded;
- }
- }
- }
-
my $target_action = $path->$_isa('Catalyst::Action') ? $path : undef;
if ( $path->$_isa('Catalyst::Action') ) { # action object
- s|/|%2F|g for @encoded_args;
+ s|/|%2F|g for @args;
my $captures = [ map { s|/|%2F|g; $_; }
- ( scalar @encoded_args && ref $encoded_args[0] eq 'ARRAY'
- ? @{ shift(@encoded_args) }
+ ( scalar @args && ref $args[0] eq 'ARRAY'
+ ? @{ shift(@args) }
: ()) ];
my $action = $path;
+ my $expanded_action = $c->dispatcher->expand_action( $action );
+ my $num_captures = $expanded_action->number_of_captures;
+
# ->uri_for( $action, \@captures_and_args, \%query_values? )
- if( !@encoded_args && $action->number_of_args ) {
- my $expanded_action = $c->dispatcher->expand_action( $action );
- my $num_captures = $expanded_action->number_of_captures;
- unshift @encoded_args, splice @$captures, $num_captures;
+ if( !@args && $action->number_of_args ) {
+ unshift @args, splice @$captures, $num_captures;
}
- $path = $c->dispatcher->uri_for_action($action, $captures);
+ if($num_captures) {
+ unless($expanded_action->match_captures_constraints($c, $captures)) {
+ carp "captures [@{$captures}] do not match the type constraints in actionchain ending with '$expanded_action'";
+ return;
+ }
+ }
+
+ $path = $c->dispatcher->uri_for_action($action, $captures);
if (not defined $path) {
$c->log->debug(qq/Can't find uri_for action '$action' @$captures/)
if $c->debug;
return undef;
}
$path = '/' if $path eq '';
+
+ # At this point @encoded_args is the remaining Args (all captures removed).
+ if($expanded_action->has_args_constraints) {
+ unless($expanded_action->match_args($c,\@args)) {
+ carp "args [@args] do not match the type constraints in action '$expanded_action'";
+ return;
+ }
+ }
}
- unshift(@encoded_args, $path);
+ unshift(@args, $path);
unless (defined $path && $path =~ s!^/!!) { # in-place strip
my $namespace = $c->namespace;
if (defined $path) { # cheesy hack to handle path '../foo'
- $namespace =~ s{(?:^|/)[^/]+$}{} while $encoded_args[0] =~ s{^\.\./}{};
+ $namespace =~ s{(?:^|/)[^/]+$}{} while $args[0] =~ s{^\.\./}{};
}
- unshift(@encoded_args, $namespace || '');
+ unshift(@args, $namespace || '');
}
# join args with '/', or a blank string
- my $args = join('/', grep { defined($_) } @encoded_args);
+ my $args = join('/', grep { defined($_) } @args);
$args =~ s/\?/%3F/g; # STUPID STUPID SPECIAL CASE
$args =~ s!^/+!!;
@@ -1567,6 +1656,11 @@ sub uri_for {
} @keys);
}
+ $base = encode_utf8 $base;
+ $base =~ s/([^$URI::uric])/$URI::Escape::escapes{$1}/go;
+ $args = encode_utf8 $args;
+ $args =~ s/([^$URI::uric])/$URI::Escape::escapes{$1}/go;
+
my $res = bless(\"${base}${args}${query}", $class);
$res;
}
@@ -2154,9 +2248,10 @@ sub finalize_encoding {
# Set the charset if necessary. This might be a bit bonkers since encodable response
# is false when the set charset is not the same as the encoding mimetype (maybe
# confusing action at a distance here..
- # Don't try to set the charset if one already exists
+ # Don't try to set the charset if one already exists or if headers are already finalized
$c->res->content_type($c->res->content_type . "; charset=" . $c->encoding->mime_name)
- unless($c->res->content_type_charset);
+ unless($c->res->content_type_charset ||
+ ($c->res->_context && $c->res->finalized_headers && !$c->res->_has_response_cb));
}
}
@@ -2261,8 +2356,8 @@ sub prepare {
$c->response->_context($c);
- #surely this is not the most efficient way to do things...
$c->stats($class->stats_class->new)->enable($c->use_stats);
+
if ( $c->debug || $c->config->{enable_catalyst_header} ) {
$c->res->headers->header( 'X-Catalyst' => $Catalyst::VERSION );
}
@@ -2668,10 +2763,65 @@ sub prepare_write { my $c = shift; $c->engine->prepare_write( $c, @_ ) }
Returns or sets the request class. Defaults to L.
+=head2 $app->request_class_traits
+
+An arrayref of Ls which are applied to the request class. You can
+name the full namespace of the role, or a namespace suffix, which will then
+be tried against the following standard namespace prefixes.
+
+ $MyApp::TraitFor::Request::$trait_suffix
+ Catalyst::TraitFor::Request::$trait_suffix
+
+So for example if you set:
+
+ MyApp->request_class_traits(['Foo']);
+
+We try each possible role in turn (and throw an error if none load)
+
+ Foo
+ MyApp::TraitFor::Request::Foo
+ Catalyst::TraitFor::Request::Foo
+
+The namespace part 'TraitFor::Request' was choosen to assist in backwards
+compatibility with L which previously provided
+these features in a stand alone package.
+
+=head2 $app->composed_request_class
+
+This is the request class which has been composed with any request_class_traits.
+
=head2 $c->response_class
Returns or sets the response class. Defaults to L.
+=head2 $app->response_class_traits
+
+An arrayref of Ls which are applied to the response class. You can
+name the full namespace of the role, or a namespace suffix, which will then
+be tried against the following standard namespace prefixes.
+
+ $MyApp::TraitFor::Response::$trait_suffix
+ Catalyst::TraitFor::Response::$trait_suffix
+
+So for example if you set:
+
+ MyApp->response_class_traits(['Foo']);
+
+We try each possible role in turn (and throw an error if none load)
+
+ Foo
+ MyApp::TraitFor::Response::Foo
+ Catalyst::TraitFor::Responset::Foo
+
+The namespace part 'TraitFor::Response' was choosen to assist in backwards
+compatibility with L which previously provided
+these features in a stand alone package.
+
+
+=head2 $app->composed_response_class
+
+This is the request class which has been composed with any response_class_traits.
+
=head2 $c->read( [$maxlength] )
Reads a chunk of data from the request body. This method is designed to
@@ -2780,17 +2930,119 @@ sub setup_components {
}
for my $component (@comps) {
- my $instance = $class->components->{ $component } = $class->setup_component($component);
- my @expanded_components = $instance->can('expand_modules')
- ? $instance->expand_modules( $component, $config )
- : $class->expand_component_module( $component, $config );
- for my $component (@expanded_components) {
- next if $comps{$component};
- $class->components->{ $component } = $class->setup_component($component);
- }
+ my $instance = $class->components->{ $component } = $class->delayed_setup_component($component);
+ }
+
+ # Inject a component or wrap a stand alone class in an adaptor. This makes a list
+ # of named components in the configuration that are not actually existing (not a
+ # real file).
+
+ my @injected = $class->setup_injected_components;
+
+ # All components are registered, now we need to 'init' them.
+ foreach my $component_name (@comps, @injected) {
+ $class->components->{$component_name} = $class->components->{$component_name}->() if
+ (ref($class->components->{$component_name}) || '') eq 'CODE';
}
}
+=head2 $app->setup_injected_components
+
+Called by setup_compoents to setup components that are injected.
+
+=cut
+
+sub setup_injected_components {
+ my ($class) = @_;
+ my @injected_components = keys %{$class->config->{inject_components} ||+{}};
+
+ foreach my $injected_comp_name(@injected_components) {
+ $class->setup_injected_component(
+ $injected_comp_name,
+ $class->config->{inject_components}->{$injected_comp_name});
+ }
+
+ return map { $class ."::" . $_ }
+ @injected_components;
+}
+
+=head2 $app->setup_injected_component( $injected_component_name, $config )
+
+Setup a given injected component.
+
+=cut
+
+sub setup_injected_component {
+ my ($class, $injected_comp_name, $config) = @_;
+ if(my $component_class = $config->{from_component}) {
+ my @roles = @{$config->{roles} ||[]};
+ Catalyst::Utils::inject_component(
+ into => $class,
+ component => $component_class,
+ (scalar(@roles) ? (traits => \@roles) : ()),
+ as => $injected_comp_name);
+ }
+}
+
+=head2 $app->inject_component($MyApp_Component_name => \%args);
+
+Add a component that is injected at setup:
+
+ MyApp->inject_component( 'Model::Foo' => { from_component => 'Common::Foo' } );
+
+Must be called before ->setup. Expects a component name for your
+current application and \%args where
+
+=over 4
+
+=item from_component
+
+The target component being injected into your application
+
+=item roles
+
+An arrayref of Ls that are applied to your component.
+
+=back
+
+Example
+
+ MyApp->inject_component(
+ 'Model::Foo' => {
+ from_component => 'Common::Model::Foo',
+ roles => ['Role1', 'Role2'],
+ });
+
+=head2 $app->inject_components
+
+Inject a list of components:
+
+ MyApp->inject_components(
+ 'Model::FooOne' => {
+ from_component => 'Common::Model::Foo',
+ roles => ['Role1', 'Role2'],
+ },
+ 'Model::FooTwo' => {
+ from_component => 'Common::Model::Foo',
+ roles => ['Role1', 'Role2'],
+ });
+
+=cut
+
+sub inject_component {
+ my ($app, $name, $args) = @_;
+ die "Component $name exists" if
+ $app->config->{inject_components}->{$name};
+ $app->config->{inject_components}->{$name} = $args;
+}
+
+sub inject_components {
+ my $app = shift;
+ while(@_) {
+ $app->inject_component(shift, shift);
+ }
+}
+
=head2 $c->locate_components( $setup_component_config )
This method is meant to provide a list of component modules that should be
@@ -2832,6 +3084,21 @@ sub expand_component_module {
return Devel::InnerPackage::list_packages( $module );
}
+=head2 $app->delayed_setup_component
+
+Returns a coderef that points to a setup_component instance. Used
+internally for when you want to delay setup until the first time
+the component is called.
+
+=cut
+
+sub delayed_setup_component {
+ my($class, $component, @more) = @_;
+ return sub {
+ return my $instance = $class->setup_component($component, @more);
+ };
+}
+
=head2 $c->setup_component
=cut
@@ -2843,21 +3110,21 @@ sub setup_component {
return $component;
}
- my $suffix = Catalyst::Utils::class2classsuffix( $component );
- my $config = $class->config->{ $suffix } || {};
+ my $config = $class->config_for($component);
# Stash catalyst_component_name in the config here, so that custom COMPONENT
# methods also pass it. local to avoid pointlessly shitting in config
# for the debug screen, as $component is already the key name.
local $config->{catalyst_component_name} = $component;
- my $instance = eval { $component->COMPONENT( $class, $config ); };
-
- if ( my $error = $@ ) {
- chomp $error;
- Catalyst::Exception->throw(
- message => qq/Couldn't instantiate component "$component", "$error"/
- );
- }
+ my $instance = eval {
+ $component->COMPONENT( $class, $config );
+ } || do {
+ my $error = $@;
+ chomp $error;
+ Catalyst::Exception->throw(
+ message => qq/Couldn't instantiate component "$component", "$error"/
+ );
+ };
unless (blessed $instance) {
my $metaclass = Moose::Util::find_meta($component);
@@ -2869,7 +3136,43 @@ sub setup_component {
qq/Couldn't instantiate component "$component", COMPONENT() method (from $component_method_from) didn't return an object-like value (value was $value)./
);
}
- return $instance;
+
+ my @expanded_components = $instance->can('expand_modules')
+ ? $instance->expand_modules( $component, $config )
+ : $class->expand_component_module( $component, $config );
+ for my $component (@expanded_components) {
+ next if $class->components->{ $component };
+ $class->components->{ $component } = $class->setup_component($component);
+ }
+
+ return $instance;
+}
+
+=head2 $app->config_for( $component_name )
+
+Return the application level configuration (which is not yet merged with any
+local component configuration, via $component_class->config) for the named
+component or component object. Example:
+
+ MyApp->config(
+ 'Model::Foo' => { a => 1, b => 2},
+ );
+
+ my $config = MyApp->config_for('MyApp::Model::Foo');
+
+In this case $config is the hashref C< {a=>1, b=>2} >.
+
+This is also handy for looking up configuration for a plugin, to make sure you follow
+existing L standards for where a plugin should put its configuration.
+
+=cut
+
+sub config_for {
+ my ($class, $component_name) = @_;
+ my $component_suffix = Catalyst::Utils::class2classsuffix($component_name);
+ my $config = $class->config->{ $component_suffix } || {};
+
+ return $config;
}
=head2 $c->setup_dispatcher
@@ -3675,6 +3978,33 @@ by itself.
Returns or sets the stats (timing statistics) class. L is used by default.
+=head2 $app->stats_class_traits
+
+A arrayref of Ls that are applied to the stats_class before creating it.
+
+=head2 $app->composed_stats_class
+
+this is the stats_class composed with any 'stats_class_traits'. You can
+name the full namespace of the role, or a namespace suffix, which will then
+be tried against the following standard namespace prefixes.
+
+ $MyApp::TraitFor::Stats::$trait_suffix
+ Catalyst::TraitFor::Stats::$trait_suffix
+
+So for example if you set:
+
+ MyApp->stats_class_traits(['Foo']);
+
+We try each possible role in turn (and throw an error if none load)
+
+ Foo
+ MyApp::TraitFor::Stats::Foo
+ Catalyst::TraitFor::Stats::Foo
+
+The namespace part 'TraitFor::Stats' was choosen to assist in backwards
+compatibility with L which previously provided
+these features in a stand alone package.
+
=head2 $c->use_stats
Returns 1 when L<< stats collection|/"-Stats" >> is enabled.
@@ -3904,12 +4234,106 @@ parameter to true.
=item *
+C
+
+If true, then do not try to character decode any wide characters in your
+request URL query or keywords. Most readings of the relevent specifications
+suggest these should be UTF-* encoded, which is the default that L
+will use, hwoever if you are creating a lot of URLs manually or have external
+evil clients, this might cause you trouble. If you find the changes introduced
+in Catalyst version 5.90080+ break some of your query code, you may disable
+the UTF-8 decoding globally using this configuration.
+
+This setting takes precedence over C and
+C
+
+=item *
+
+C
+
+By default we decode query and keywords in your request URL using UTF-8, which
+is our reading of the relevent specifications. This setting allows one to
+specify a fixed value for how to decode your query. You might need this if
+you are doing a lot of custom encoding of your URLs and not using UTF-8.
+
+This setting take precedence over C.
+
+=item *
+
+C
+
+Setting this to true will default your query decoding to whatever your
+general global encoding is (the default is UTF-8).
+
+=item *
+
+C
+
+In older versions of Catalyst, when more than one action matched the same path
+AND all those matching actions declared Args(0), we'd break the tie by choosing
+the first action defined. We now normalized how Args(0) works so that it
+follows the same rule as Args(N), which is to say when we need to break a tie
+we choose the LAST action defined. If this breaks your code and you don't
+have time to update to follow the new normalized approach, you may set this
+value to true and it will globally revert to the original chaining behavior.
+
+=item *
+
C - See L.
=item *
C - See L.
+=item *
+
+C
+
+An arrayref of Ls that get componsed into your stats class.
+
+=item *
+
+C
+
+An arrayref of Ls that get componsed into your request class.
+
+=item *
+
+C
+
+An arrayref of Ls that get componsed into your response class.
+
+=item *
+
+C
+
+A Hashref of L subclasses that are 'injected' into configuration.
+For example:
+
+ MyApp->config({
+ inject_components => {
+ 'Controller::Err' => { from_component => 'Local::Controller::Errors' },
+ 'Model::Zoo' => { from_component => 'Local::Model::Foo' },
+ 'Model::Foo' => { from_component => 'Local::Model::Foo', roles => ['TestRole'] },
+ },
+ 'Controller::Err' => { a => 100, b=>200, namespace=>'error' },
+ 'Model::Zoo' => { a => 2 },
+ 'Model::Foo' => { a => 100 },
+ });
+
+Generally L looks for components in your Model/View or Controller directories.
+However for cases when you which to use an existing component and you don't need any
+customization (where for when you can apply a role to customize it) you may inject those
+components into your application. Please note any configuration should be done 'in the
+normal way', with a key under configuration named after the component affix, as in the
+above example.
+
+Using this type of injection allows you to construct significant amounts of your application
+with only configuration!. This may or may not lead to increased code understanding.
+
+Please not you may also call the ->inject_components application method as well, although
+you must do so BEFORE setup.
+
=back
=head1 EXCEPTIONS