X-Git-Url: http://git.shadowcat.co.uk/gitweb/gitweb.cgi?p=catagits%2FCatalyst-Runtime.git;a=blobdiff_plain;f=lib%2FCatalyst%2FDispatchType%2FChained.pm;h=e29e5b5916d4fdaa1b26cba8390cca4786f49bcd;hp=132d9efb443f2465604b77a78b79e24106dd049d;hb=342d21698a97962c51114b6ebc6bb8626511cfc6;hpb=5882c86e1f256e122583dcc311b17bdbf9a4d766 diff --git a/lib/Catalyst/DispatchType/Chained.pm b/lib/Catalyst/DispatchType/Chained.pm index 132d9ef..e29e5b5 100644 --- a/lib/Catalyst/DispatchType/Chained.pm +++ b/lib/Catalyst/DispatchType/Chained.pm @@ -1,10 +1,37 @@ package Catalyst::DispatchType::Chained; -use strict; -use base qw/Catalyst::DispatchType/; +use Moose; +extends 'Catalyst::DispatchType'; + use Text::SimpleTable; use Catalyst::ActionChain; +use Catalyst::Utils; use URI; +use Scalar::Util (); +use Encode 2.21 'decode_utf8'; + +has _endpoints => ( + is => 'rw', + isa => 'ArrayRef', + required => 1, + default => sub{ [] }, + ); + +has _actions => ( + is => 'rw', + isa => 'HashRef', + required => 1, + default => sub{ {} }, + ); + +has _children_of => ( + is => 'rw', + isa => 'HashRef', + required => 1, + default => sub{ {} }, + ); + +no Moose; # please don't perltidy this. hairy code within. @@ -14,10 +41,33 @@ Catalyst::DispatchType::Chained - Path Part DispatchType =head1 SYNOPSIS -See L. +Path part matching, allowing several actions to sequentially take care of processing a request: + + # root action - captures one argument after it + sub foo_setup : Chained('/') PathPart('foo') CaptureArgs(1) { + my ( $self, $c, $foo_arg ) = @_; + ... + } + + # child action endpoint - takes one argument + sub bar : Chained('foo_setup') Args(1) { + my ( $self, $c, $bar_arg ) = @_; + ... + } =head1 DESCRIPTION +Dispatch type managing default behaviour. For more information on +dispatch types, see: + +=over 4 + +=item * L for how they affect application authors + +=item * L for implementation information. + +=back + =head1 METHODS =head2 $self->list($c) @@ -29,75 +79,131 @@ Debug output for Path Part dispatch points sub list { my ( $self, $c ) = @_; - return unless $self->{endpoints}; + return unless $self->_endpoints; + my $avail_width = Catalyst::Utils::term_width() - 9; + my $col1_width = ($avail_width * .50) < 35 ? 35 : int($avail_width * .50); + my $col2_width = $avail_width - $col1_width; my $paths = Text::SimpleTable->new( - [ 35, 'Path Spec' ], [ 36, 'Private' ] - ); + [ $col1_width, 'Path Spec' ], [ $col2_width, 'Private' ], + ); + + my $has_unattached_actions; + my $unattached_actions = Text::SimpleTable->new( + [ $col1_width, 'Private' ], [ $col2_width, 'Missing parent' ], + ); ENDPOINT: foreach my $endpoint ( sort { $a->reverse cmp $b->reverse } - @{ $self->{endpoints} } + @{ $self->_endpoints } ) { - my $args = $endpoint->attributes->{Args}->[0]; + my $args = $endpoint->list_extra_info->{Args}; my @parts = (defined($args) ? (("*") x $args) : '...'); my @parents = (); my $parent = "DUMMY"; + my $extra = $self->_list_extra_http_methods($endpoint); + my $consumes = $self->_list_extra_consumes($endpoint); + my $scheme = $self->_list_extra_scheme($endpoint); my $curr = $endpoint; while ($curr) { - if (my $cap = $curr->attributes->{Captures}) { - unshift(@parts, (("*") x $cap->[0])); + if (my $cap = $curr->list_extra_info->{CaptureArgs}) { + unshift(@parts, (("*") x $cap)); } - if (my $pp = $curr->attributes->{PartPath}) { + if (my $pp = $curr->attributes->{PathPart}) { unshift(@parts, $pp->[0]) if (defined $pp->[0] && length $pp->[0]); } $parent = $curr->attributes->{Chained}->[0]; - $curr = $self->{actions}{$parent}; + $curr = $self->_actions->{$parent}; unshift(@parents, $curr) if $curr; } - next ENDPOINT unless $parent eq '/'; # skip dangling action + if ($parent ne '/') { + $has_unattached_actions = 1; + $unattached_actions->row('/' . ($parents[0] || $endpoint)->reverse, $parent); + next ENDPOINT; + } my @rows; foreach my $p (@parents) { my $name = "/${p}"; - if (my $cap = $p->attributes->{Captures}) { - $name .= ' ('.$cap->[0].')'; + + if (defined(my $extra = $self->_list_extra_http_methods($p))) { + $name = "${extra} ${name}"; + } + if (defined(my $cap = $p->list_extra_info->{CaptureArgs})) { + $name .= ' ('.$cap.')'; } + if (defined(my $ct = $p->list_extra_info->{Consumes})) { + $name .= ' :'.$ct; + } + if (defined(my $s = $p->list_extra_info->{Scheme})) { + $scheme = uc $s; + } + unless ($p eq $parents[0]) { $name = "-> ${name}"; } push(@rows, [ '', $name ]); } - push(@rows, [ '', (@rows ? "=> " : '')."/${endpoint}" ]); - $rows[0][0] = join('/', '', @parts); + push(@rows, [ '', (@rows ? "=> " : '').($extra ? "$extra " : ''). ($scheme ? "$scheme: ":'')."/${endpoint}". ($consumes ? " :$consumes":"" ) ]); + my @display_parts = map { $_ =~s/%([0-9A-Fa-f]{2})/chr(hex($1))/eg; decode_utf8 $_ } @parts; + $rows[0][0] = join('/', '', @display_parts) || '/'; $paths->row(@$_) for @rows; } - $c->log->debug( "Loaded Path Part actions:\n" . $paths->draw ); + $c->log->debug( "Loaded Chained actions:\n" . $paths->draw . "\n" ); + $c->log->debug( "Unattached Chained actions:\n", $unattached_actions->draw . "\n" ) + if $has_unattached_actions; +} + +sub _list_extra_http_methods { + my ( $self, $action ) = @_; + return unless defined $action->list_extra_info->{HTTP_METHODS}; + return join(', ', @{$action->list_extra_info->{HTTP_METHODS}}); + +} + +sub _list_extra_consumes { + my ( $self, $action ) = @_; + return unless defined $action->list_extra_info->{CONSUMES}; + return join(', ', @{$action->list_extra_info->{CONSUMES}}); +} + +sub _list_extra_scheme { + my ( $self, $action ) = @_; + return unless defined $action->list_extra_info->{Scheme}; + return uc $action->list_extra_info->{Scheme}; } =head2 $self->match( $c, $path ) -Matt is an idiot and hasn't documented this yet. +Calls C to see if a chain matches the C<$path>. =cut sub match { my ( $self, $c, $path ) = @_; - return 0 if @{$c->req->args}; + my $request = $c->request; + return 0 if @{$request->args}; my @parts = split('/', $path); - my ($chain, $captures) = $self->recurse_match($c, '/', \@parts); + my ($chain, $captures, $parts) = $self->recurse_match($c, '/', \@parts); + + if ($parts && @$parts) { + for my $arg (@$parts) { + $arg =~ s/%([0-9A-Fa-f]{2})/chr(hex($1))/eg; + push @{$request->args}, $arg; + } + } return 0 unless $chain; my $action = Catalyst::ActionChain->from_chain($chain); - $c->req->action("/${action}"); - $c->req->match("/${action}"); - $c->req->captures($captures); + $request->action("/${action}"); + $request->match("/${action}"); + $request->captures($captures); $c->action($action); $c->namespace( $action->namespace ); @@ -106,17 +212,19 @@ sub match { =head2 $self->recurse_match( $c, $parent, \@path_parts ) -Matt is an idiot and hasn't documented this yet. +Recursive search for a matching chain. =cut sub recurse_match { my ( $self, $c, $parent, $path_parts ) = @_; - my $children = $self->{children_of}{$parent}; + my $children = $self->_children_of->{$parent}; return () unless $children; + my $best_action; my @captures; - TRY: foreach my $try_part (sort { length($a) <=> length($b) } + TRY: foreach my $try_part (sort { length($b) <=> length($a) } keys %$children) { + # $b then $a to try longest part first my @parts = @$path_parts; if (length $try_part) { # test and strip PathPart next TRY unless @@ -127,65 +235,125 @@ sub recurse_match { } my @try_actions = @{$children->{$try_part}}; TRY_ACTION: foreach my $action (@try_actions) { - if (my $capture_attr = $action->attributes->{Captures}) { + if (my $capture_attr = $action->attributes->{CaptureArgs}) { + my $capture_count = $capture_attr->[0] || 0; + + # Short-circuit if not enough remaining parts + next TRY_ACTION unless @parts >= $capture_count; + my @captures; my @parts = @parts; # localise - # strip Captures into list - push(@captures, splice(@parts, 0, $capture_attr->[0])); + # strip CaptureArgs into list + push(@captures, splice(@parts, 0, $capture_count)); + + # check if the action may fit, depending on a given test by the app + if ($action->can('match_captures')) { next TRY_ACTION unless $action->match_captures($c, \@captures) } # try the remaining parts against children of this action - my ($actions, $captures) = $self->recurse_match( + my ($actions, $captures, $action_parts, $n_pathparts) = $self->recurse_match( $c, '/'.$action->reverse, \@parts ); - if ($actions) { - return [ $action, @$actions ], [ @captures, @$captures ]; + # No best action currently + # OR The action has less parts + # OR The action has equal parts but less captured data (ergo more defined) + if ($actions && + (!$best_action || + $#$action_parts < $#{$best_action->{parts}} || + ($#$action_parts == $#{$best_action->{parts}} && + $#$captures < $#{$best_action->{captures}} && + $n_pathparts > $best_action->{n_pathparts}))) { + my @pathparts = split /\//, $action->attributes->{PathPart}->[0]; + $best_action = { + actions => [ $action, @$actions ], + captures=> [ @captures, @$captures ], + parts => $action_parts, + n_pathparts => scalar(@pathparts) + $n_pathparts, + }; } - } else { + } + else { { local $c->req->{arguments} = [ @{$c->req->args}, @parts ]; next TRY_ACTION unless $action->match($c); } - push(@{$c->req->args}, @parts); - return [ $action ], [ ]; + my $args_attr = $action->attributes->{Args}->[0]; + my @pathparts = split /\//, $action->attributes->{PathPart}->[0]; + # No best action currently + # OR This one matches with fewer parts left than the current best action, + # And therefore is a better match + # OR No parts and this expects 0 + # The current best action might also be Args(0), + # but we couldn't chose between then anyway so we'll take the last seen + + if (!$best_action || + @parts < @{$best_action->{parts}} || + (!@parts && defined($args_attr) && $args_attr eq "0")){ + $best_action = { + actions => [ $action ], + captures=> [], + parts => \@parts, + n_pathparts => scalar(@pathparts), + }; + } } } } + return @$best_action{qw/actions captures parts n_pathparts/} if $best_action; return (); } =head2 $self->register( $c, $action ) -Matt is an idiot and hasn't documented this yet. +Calls register_path for every Path attribute for the given $action. =cut +sub _check_args_attr { + my ( $self, $action, $name ) = @_; + + return unless exists $action->attributes->{$name}; + + if (@{$action->attributes->{$name}} > 1) { + Catalyst::Exception->throw( + "Multiple $name attributes not supported registering " . $action->reverse() + ); + } + my $args = $action->attributes->{$name}->[0]; + if (defined($args) and not ( + Scalar::Util::looks_like_number($args) and + int($args) == $args and $args >= 0 + )) { + require Data::Dumper; + local $Data::Dumper::Terse = 1; + local $Data::Dumper::Indent = 0; + $args = Data::Dumper::Dumper($args); + Catalyst::Exception->throw( + "Invalid $name($args) for action " . $action->reverse() . + " (use '$name' or '$name()')" + ); + } +} + sub register { my ( $self, $c, $action ) = @_; - my @child_of_attr = @{ $action->attributes->{Chained} || [] }; + my @chained_attr = @{ $action->attributes->{Chained} || [] }; - return 0 unless @child_of_attr; + return 0 unless @chained_attr; - if (@child_of_attr > 2) { + if (@chained_attr > 1) { Catalyst::Exception->throw( "Multiple Chained attributes not supported registering ${action}" ); } + my $chained_to = $chained_attr[0]; - my $parent = $child_of_attr[0]; - - if (defined($parent) && length($parent)) { - unless ($parent =~ m/^\//) { - $parent = '/'.join('/', $action->namespace, $parent); - } - } else { - $parent = '/'.$action->namespace; - } - - $action->attributes->{Chained} = [ $parent ]; + Catalyst::Exception->throw( + "Actions cannot chain to themselves registering /${action}" + ) if ($chained_to eq '/' . $action); - my $children = ($self->{children_of}{$parent} ||= {}); + my $children = ($self->_children_of->{ $chained_to } ||= {}); my @path_part = @{ $action->attributes->{PathPart} || [] }; @@ -195,18 +363,38 @@ sub register { $part = $path_part[0]; } elsif (@path_part > 1) { Catalyst::Exception->throw( - "Multiple PathPart attributes not supported registering ${action}" + "Multiple PathPart attributes not supported registering " . $action->reverse() ); } - $action->attributes->{PartPath} = [ $part ]; + if ($part =~ m(^/)) { + Catalyst::Exception->throw( + "Absolute parameters to PathPart not allowed registering " . $action->reverse() + ); + } + + my $encoded_part = URI->new($part)->canonical; + $encoded_part =~ s{(?<=[^/])/+\z}{}; + + $action->attributes->{PathPart} = [ $encoded_part ]; + + unshift(@{ $children->{$encoded_part} ||= [] }, $action); + + $self->_actions->{'/'.$action->reverse} = $action; - unshift(@{ $children->{$part} ||= [] }, $action); + foreach my $name (qw(Args CaptureArgs)) { + $self->_check_args_attr($action, $name); + } - ($self->{actions} ||= {})->{'/'.$action->reverse} = $action; + if (exists $action->attributes->{Args} and exists $action->attributes->{CaptureArgs}) { + Catalyst::Exception->throw( + "Combining Args and CaptureArgs attributes not supported registering " . + $action->reverse() + ); + } - unless ($action->attributes->{Captures}) { - unshift(@{ $self->{endpoints} ||= [] }, $action); + unless ($action->attributes->{CaptureArgs}) { + unshift(@{ $self->_endpoints }, $action); } return 1; @@ -214,7 +402,8 @@ sub register { =head2 $self->uri_for_action($action, $captures) -Matt is an idiot and hasn't documented this yet. +Get the URI part for the action, using C<$captures> to fill +the capturing parts. =cut @@ -222,23 +411,25 @@ sub uri_for_action { my ( $self, $action, $captures ) = @_; return undef unless ($action->attributes->{Chained} - && $action->attributes->{Args}); + && !$action->attributes->{CaptureArgs}); my @parts = (); my @captures = @$captures; my $parent = "DUMMY"; my $curr = $action; while ($curr) { - if (my $cap = $curr->attributes->{Captures}) { - return undef unless @captures >= $cap->[0]; # not enough captures - unshift(@parts, splice(@captures, -$cap->[0])); + if (my $cap = $curr->attributes->{CaptureArgs}) { + return undef unless @captures >= ($cap->[0]||0); # not enough captures + if ($cap->[0]) { + unshift(@parts, splice(@captures, -$cap->[0])); + } } - if (my $pp = $curr->attributes->{PartPath}) { + if (my $pp = $curr->attributes->{PathPart}) { unshift(@parts, $pp->[0]) - if (defined $pp->[0] && length $pp->[0]); + if (defined($pp->[0]) && length($pp->[0])); } $parent = $curr->attributes->{Chained}->[0]; - $curr = $self->{actions}{$parent}; + $curr = $self->_actions->{$parent}; } return undef unless $parent eq '/'; # fail for dangling action @@ -246,16 +437,321 @@ sub uri_for_action { return undef if @captures; # fail for too many captures return join('/', '', @parts); - + +} + +=head2 $c->expand_action($action) + +Return a list of actions that represents a chained action. See +L for more info. You probably want to +use the expand_action it provides rather than this directly. + +=cut + +sub expand_action { + my ($self, $action) = @_; + + return unless $action->attributes && $action->attributes->{Chained}; + + my @chain; + my $curr = $action; + + while ($curr) { + push @chain, $curr; + my $parent = $curr->attributes->{Chained}->[0]; + $curr = $self->_actions->{$parent}; + } + + return Catalyst::ActionChain->from_chain([reverse @chain]); } -=head1 AUTHOR +__PACKAGE__->meta->make_immutable; +1; + +=head1 USAGE + +=head2 Introduction + +The C attribute allows you to chain public path parts together +by their private names. A chain part's path can be specified with +C and can be declared to expect an arbitrary number of +arguments. The endpoint of the chain specifies how many arguments it +gets through the C attribute. C<:Args(0)> would be none at all, +C<:Args> without an integer would be unlimited. The path parts that +aren't endpoints are using C to specify how many parameters +they expect to receive. As an example setup: + + package MyApp::Controller::Greeting; + use base qw/ Catalyst::Controller /; + + # this is the beginning of our chain + sub hello : PathPart('hello') Chained('/') CaptureArgs(1) { + my ( $self, $c, $integer ) = @_; + $c->stash->{ message } = "Hello "; + $c->stash->{ arg_sum } = $integer; + } + + # this is our endpoint, because it has no :CaptureArgs + sub world : PathPart('world') Chained('hello') Args(1) { + my ( $self, $c, $integer ) = @_; + $c->stash->{ message } .= "World!"; + $c->stash->{ arg_sum } += $integer; + + $c->response->body( join "
\n" => + $c->stash->{ message }, $c->stash->{ arg_sum } ); + } + +The debug output provides a separate table for chained actions, showing +the whole chain as it would match and the actions it contains. Here's an +example of the startup output with our actions above: + + ... + [debug] Loaded Path Part actions: + .-----------------------+------------------------------. + | Path Spec | Private | + +-----------------------+------------------------------+ + | /hello/*/world/* | /greeting/hello (1) | + | | => /greeting/world | + '-----------------------+------------------------------' + ... + +As you can see, Catalyst only deals with chains as whole paths and +builds one for each endpoint, which are the actions with C<:Chained> but +without C<:CaptureArgs>. + +Let's assume this application gets a request at the path +C. What happens then? First, Catalyst will dispatch +to the C action and pass the value C<23> as an argument to it +after the context. It does so because we have previously used +C<:CaptureArgs(1)> to declare that it has one path part after itself as +its argument. We told Catalyst that this is the beginning of the chain +by specifying C<:Chained('/')>. Also note that instead of saying +C<:PathPart('hello')> we could also just have said C<:PathPart>, as it +defaults to the name of the action. + +After C has run, Catalyst goes on to dispatch to the C +action. This is the last action to be called: Catalyst knows this is an +endpoint because we did not specify a C<:CaptureArgs> +attribute. Nevertheless we specify that this action expects an argument, +but at this point we're using C<:Args(1)> to do that. We could also have +said C<:Args> or left it out altogether, which would mean this action +would get all arguments that are there. This action's C<:Chained> +attribute says C and tells Catalyst that the C action in +the current controller is its parent. + +With this we have built a chain consisting of two public path parts. +C captures one part of the path as its argument, and also +specifies the path root as its parent. So this part is +C. The next part is the endpoint C, expecting one +argument. It sums up to the path part C. This leads to a +complete chain of C which is matched against the +requested paths. + +This example application would, if run and called by e.g. +C, set the stash value C to "Hello" and the +value C to "23". The C action would then append "World!" +to C and add C<12> to the stash's C value. For the +sake of simplicity no view is shown. Instead we just put the values of +the stash into our body. So the output would look like: + + Hello World! + 35 + +And our test server would have given us this debugging output for the +request: + + ... + [debug] "GET" request for "hello/23/world/12" from "127.0.0.1" + [debug] Path is "/greeting/world" + [debug] Arguments are "12" + [info] Request took 0.164113s (6.093/s) + .------------------------------------------+-----------. + | Action | Time | + +------------------------------------------+-----------+ + | /greeting/hello | 0.000029s | + | /greeting/world | 0.000024s | + '------------------------------------------+-----------' + ... + +What would be common uses of this dispatch technique? It gives the +possibility to split up logic that contains steps that each depend on +each other. An example would be, for example, a wiki path like +C. This chain can be easily built with +these actions: + + sub wiki : PathPart('wiki') Chained('/') CaptureArgs(1) { + my ( $self, $c, $page_name ) = @_; + # load the page named $page_name and put the object + # into the stash + } + + sub rev : PathPart('rev') Chained('wiki') CaptureArgs(1) { + my ( $self, $c, $revision_id ) = @_; + # use the page object in the stash to get at its + # revision with number $revision_id + } + + sub view : PathPart Chained('rev') Args(0) { + my ( $self, $c ) = @_; + # display the revision in our stash. Another option + # would be to forward a compatible object to the action + # that displays the default wiki pages, unless we want + # a different interface here, for example restore + # functionality. + } + +It would now be possible to add other endpoints, for example C +to restore this specific revision as the current state. + +You don't have to put all the chained actions in one controller. The +specification of the parent through C<:Chained> also takes an absolute +action path as its argument. Just specify it with a leading C. + +If you want, for example, to have actions for the public paths +C and C, just specify two actions with +C<:PathPart('foo')> and C<:Chained('/')>. The handler for the former +path needs a C<:CaptureArgs(1)> attribute and a endpoint with +C<:PathPart('edit')> and C<:Chained('foo')>. For the latter path give +the action just a C<:Args(1)> to mark it as endpoint. This sums up to +this debugging output: + + ... + [debug] Loaded Path Part actions: + .-----------------------+------------------------------. + | Path Spec | Private | + +-----------------------+------------------------------+ + | /foo/* | /controller/foo_view | + | /foo/*/edit | /controller/foo_load (1) | + | | => /controller/edit | + '-----------------------+------------------------------' + ... + +Here's a more detailed specification of the attributes belonging to +C<:Chained>: + +=head2 Attributes + +=over 8 + +=item PathPart + +Sets the name of this part of the chain. If it is specified without +arguments, it takes the name of the action as default. So basically +C and C are identical. +This can also contain slashes to bind to a deeper level. An action +with C would bind to +C. If you don't specify C<:PathPart> it has the same +effect as using C<:PathPart>, it would default to the action name. + +=item PathPrefix + +Sets PathPart to the path_prefix of the current controller. + +=item Chained + +Has to be specified for every child in the chain. Possible values are +absolute and relative private action paths or a single slash C to +tell Catalyst that this is the root of a chain. The attribute +C<:Chained> without arguments also defaults to the C behavior. +Relative action paths may use C<../> to refer to actions in parent +controllers. + +Because you can specify an absolute path to the parent action, it +doesn't matter to Catalyst where that parent is located. So, if your +design requests it, you can redispatch a chain through any controller or +namespace you want. + +Another interesting possibility gives C<:Chained('.')>, which chains +itself to an action with the path of the current controller's namespace. +For example: + + # in MyApp::Controller::Foo + sub bar : Chained CaptureArgs(1) { ... } + + # in MyApp::Controller::Foo::Bar + sub baz : Chained('.') Args(1) { ... } + +This builds up a chain like C. The specification of C<.> +as the argument to Chained here chains the C action to an action +with the path of the current controller namespace, namely +C. That action chains directly to C, so the C +chain comes out as the end product. + +=item ChainedParent + +Chains an action to another action with the same name in the parent +controller. For Example: + + # in MyApp::Controller::Foo + sub bar : Chained CaptureArgs(1) { ... } + + # in MyApp::Controller::Foo::Moo + sub bar : ChainedParent Args(1) { ... } + +This builds a chain like C. + +=item CaptureArgs + +Must be specified for every part of the chain that is not an +endpoint. With this attribute Catalyst knows how many of the following +parts of the path (separated by C) this action wants to capture as +its arguments. If it doesn't expect any, just specify +C<:CaptureArgs(0)>. The captures get passed to the action's C<@_> right +after the context, but you can also find them as array references in +C<$c-Erequest-Ecaptures-E[$level]>. The C<$level> is the +level of the action in the chain that captured the parts of the path. + +An action that is part of a chain (that is, one that has a C<:Chained> +attribute) but has no C<:CaptureArgs> attribute is treated by Catalyst +as a chain end. + +=item Args + +By default, endpoints receive the rest of the arguments in the path. You +can tell Catalyst through C<:Args> explicitly how many arguments your +endpoint expects, just like you can with C<:CaptureArgs>. Note that this +also affects whether this chain is invoked on a request. A chain with an +endpoint specifying one argument will only match if exactly one argument +exists in the path. + +You can specify an exact number of arguments like C<:Args(3)>, including +C<0>. If you just say C<:Args> without any arguments, it is the same as +leaving it out altogether: The chain is matched regardless of the number +of path parts after the endpoint. + +Just as with C<:CaptureArgs>, the arguments get passed to the action in +C<@_> after the context object. They can also be reached through +C<$c-Erequest-Earguments>. + +=back + +=head2 Auto actions, dispatching and forwarding + +Note that the list of C actions called depends on the private path +of the endpoint of the chain, not on the chained actions way. The +C actions will be run before the chain dispatching begins. In +every other aspect, C actions behave as documented. + +The Cing to other actions does just what you would expect. i.e. +only the target action is run. The actions that that action is chained +to are not run. +If you C out of a chain, the rest of the chain will not get +called after the C. + +=head2 match_captures + +A method which can optionally be implemented by actions to +stop chain matching. + +See L for further details. + +=head1 AUTHORS -Matt S Trout +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