Commit | Line | Data |
5882c86e |
1 | package Catalyst::DispatchType::Chained; |
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2 | |
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3 | use Moose; |
e8b9f2a9 |
4 | extends 'Catalyst::DispatchType'; |
5 | |
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6 | use Text::SimpleTable; |
7 | use Catalyst::ActionChain; |
39fc2ce1 |
8 | use Catalyst::Utils; |
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9 | use URI; |
dd97c1ac |
10 | use Scalar::Util (); |
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11 | |
be5cb4e4 |
12 | has _endpoints => ( |
13 | is => 'rw', |
14 | isa => 'ArrayRef', |
15 | required => 1, |
16 | default => sub{ [] }, |
17 | ); |
18 | |
19 | has _actions => ( |
20 | is => 'rw', |
21 | isa => 'HashRef', |
22 | required => 1, |
23 | default => sub{ {} }, |
24 | ); |
25 | |
26 | has _children_of => ( |
27 | is => 'rw', |
28 | isa => 'HashRef', |
29 | required => 1, |
30 | default => sub{ {} }, |
31 | ); |
32 | |
0fc2d522 |
33 | no Moose; |
34 | |
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35 | # please don't perltidy this. hairy code within. |
36 | |
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37 | =head1 NAME |
38 | |
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39 | Catalyst::DispatchType::Chained - Path Part DispatchType |
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40 | |
41 | =head1 SYNOPSIS |
42 | |
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43 | Path part matching, allowing several actions to sequentially take care of processing a request: |
44 | |
05a90578 |
45 | # root action - captures one argument after it |
46 | sub foo_setup : Chained('/') PathPart('foo') CaptureArgs(1) { |
47 | my ( $self, $c, $foo_arg ) = @_; |
48 | ... |
49 | } |
50 | |
51 | # child action endpoint - takes one argument |
52 | sub bar : Chained('foo_setup') Args(1) { |
53 | my ( $self, $c, $bar_arg ) = @_; |
54 | ... |
55 | } |
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56 | |
57 | =head1 DESCRIPTION |
58 | |
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59 | Dispatch type managing default behaviour. For more information on |
60 | dispatch types, see: |
61 | |
62 | =over 4 |
63 | |
b9b89145 |
64 | =item * L<Catalyst::Manual::Intro> for how they affect application authors |
26dc649a |
65 | |
66 | =item * L<Catalyst::DispatchType> for implementation information. |
67 | |
68 | =back |
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69 | |
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70 | =head1 METHODS |
71 | |
72 | =head2 $self->list($c) |
73 | |
74 | Debug output for Path Part dispatch points |
75 | |
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76 | =cut |
77 | |
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78 | sub list { |
79 | my ( $self, $c ) = @_; |
80 | |
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81 | return unless $self->_endpoints; |
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82 | |
48d435ba |
83 | my $avail_width = Catalyst::Utils::term_width() - 9; |
84 | my $col1_width = ($avail_width * .50) < 35 ? 35 : int($avail_width * .50); |
85 | my $col2_width = $avail_width - $col1_width; |
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86 | my $paths = Text::SimpleTable->new( |
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87 | [ $col1_width, 'Path Spec' ], [ $col2_width, 'Private' ], |
39fc2ce1 |
88 | ); |
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89 | |
007a7ca0 |
90 | my $has_unattached_actions; |
91 | my $unattached_actions = Text::SimpleTable->new( |
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92 | [ $col1_width, 'Private' ], [ $col2_width, 'Missing parent' ], |
007a7ca0 |
93 | ); |
94 | |
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95 | ENDPOINT: foreach my $endpoint ( |
96 | sort { $a->reverse cmp $b->reverse } |
be5cb4e4 |
97 | @{ $self->_endpoints } |
792b40ac |
98 | ) { |
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99 | my $args = $endpoint->list_extra_info->{Args}; |
792b40ac |
100 | my @parts = (defined($args) ? (("*") x $args) : '...'); |
d34667c3 |
101 | my @parents = (); |
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102 | my $parent = "DUMMY"; |
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103 | my $extra = $self->_list_extra_http_methods($endpoint); |
e72a3cd6 |
104 | my $consumes = $self->_list_extra_consumes($endpoint); |
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105 | my $curr = $endpoint; |
106 | while ($curr) { |
ffca3e96 |
107 | if (my $cap = $curr->list_extra_info->{CaptureArgs}) { |
108 | unshift(@parts, (("*") x $cap)); |
792b40ac |
109 | } |
77771155 |
110 | if (my $pp = $curr->attributes->{PathPart}) { |
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111 | unshift(@parts, $pp->[0]) |
112 | if (defined $pp->[0] && length $pp->[0]); |
113 | } |
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114 | $parent = $curr->attributes->{Chained}->[0]; |
be5cb4e4 |
115 | $curr = $self->_actions->{$parent}; |
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116 | unshift(@parents, $curr) if $curr; |
792b40ac |
117 | } |
007a7ca0 |
118 | if ($parent ne '/') { |
119 | $has_unattached_actions = 1; |
59d5a638 |
120 | $unattached_actions->row('/' . ($parents[0] || $endpoint)->reverse, $parent); |
007a7ca0 |
121 | next ENDPOINT; |
122 | } |
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123 | my @rows; |
124 | foreach my $p (@parents) { |
125 | my $name = "/${p}"; |
ba3f8a81 |
126 | |
127 | if (defined(my $extra = $self->_list_extra_http_methods($p))) { |
128 | $name = "${extra} ${name}"; |
129 | } |
ffca3e96 |
130 | if (defined(my $cap = $p->list_extra_info->{CaptureArgs})) { |
131 | $name .= ' ('.$cap.')'; |
d34667c3 |
132 | } |
e72a3cd6 |
133 | if (defined(my $ct = $p->list_extra_info->{Consumes})) { |
134 | $name .= ' :'.$ct; |
135 | } |
136 | |
d34667c3 |
137 | unless ($p eq $parents[0]) { |
138 | $name = "-> ${name}"; |
139 | } |
140 | push(@rows, [ '', $name ]); |
141 | } |
e72a3cd6 |
142 | push(@rows, [ '', (@rows ? "=> " : '').($extra ? "$extra " : '')."/${endpoint}". ($consumes ? " :$consumes":"" ) ]); |
f4624073 |
143 | $rows[0][0] = join('/', '', @parts) || '/'; |
d34667c3 |
144 | $paths->row(@$_) for @rows; |
792b40ac |
145 | } |
146 | |
1cf0345b |
147 | $c->log->debug( "Loaded Chained actions:\n" . $paths->draw . "\n" ); |
007a7ca0 |
148 | $c->log->debug( "Unattached Chained actions:\n", $unattached_actions->draw . "\n" ) |
149 | if $has_unattached_actions; |
792b40ac |
150 | } |
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151 | |
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152 | sub _list_extra_http_methods { |
153 | my ( $self, $action ) = @_; |
154 | return unless defined $action->list_extra_info->{HTTP_METHODS}; |
155 | return join(', ', @{$action->list_extra_info->{HTTP_METHODS}}); |
e72a3cd6 |
156 | |
ba3f8a81 |
157 | } |
158 | |
e72a3cd6 |
159 | sub _list_extra_consumes { |
160 | my ( $self, $action ) = @_; |
161 | return unless defined $action->list_extra_info->{CONSUMES}; |
162 | return join(', ', @{$action->list_extra_info->{CONSUMES}}); |
163 | } |
164 | |
165 | |
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166 | =head2 $self->match( $c, $path ) |
167 | |
05a90578 |
168 | Calls C<recurse_match> to see if a chain matches the C<$path>. |
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169 | |
170 | =cut |
171 | |
172 | sub match { |
173 | my ( $self, $c, $path ) = @_; |
174 | |
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175 | my $request = $c->request; |
176 | return 0 if @{$request->args}; |
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177 | |
178 | my @parts = split('/', $path); |
179 | |
6365b527 |
180 | my ($chain, $captures, $parts) = $self->recurse_match($c, '/', \@parts); |
634780e0 |
181 | |
182 | if ($parts && @$parts) { |
183 | for my $arg (@$parts) { |
184 | $arg =~ s/%([0-9A-Fa-f]{2})/chr(hex($1))/eg; |
185 | push @{$request->args}, $arg; |
186 | } |
187 | } |
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188 | |
189 | return 0 unless $chain; |
190 | |
191 | my $action = Catalyst::ActionChain->from_chain($chain); |
192 | |
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193 | $request->action("/${action}"); |
194 | $request->match("/${action}"); |
195 | $request->captures($captures); |
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196 | $c->action($action); |
197 | $c->namespace( $action->namespace ); |
198 | |
199 | return 1; |
200 | } |
201 | |
202 | =head2 $self->recurse_match( $c, $parent, \@path_parts ) |
203 | |
05a90578 |
204 | Recursive search for a matching chain. |
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205 | |
206 | =cut |
207 | |
208 | sub recurse_match { |
209 | my ( $self, $c, $parent, $path_parts ) = @_; |
be5cb4e4 |
210 | my $children = $self->_children_of->{$parent}; |
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211 | return () unless $children; |
6b495723 |
212 | my $best_action; |
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213 | my @captures; |
1b04b972 |
214 | TRY: foreach my $try_part (sort { length($b) <=> length($a) } |
cdc97b63 |
215 | keys %$children) { |
1b04b972 |
216 | # $b then $a to try longest part first |
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217 | my @parts = @$path_parts; |
218 | if (length $try_part) { # test and strip PathPart |
219 | next TRY unless |
220 | ($try_part eq join('/', # assemble equal number of parts |
221 | splice( # and strip them off @parts as well |
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222 | @parts, 0, scalar(@{[split('/', $try_part)]}) |
223 | ))); # @{[]} to avoid split to @_ |
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224 | } |
225 | my @try_actions = @{$children->{$try_part}}; |
226 | TRY_ACTION: foreach my $action (@try_actions) { |
1c34f703 |
227 | if (my $capture_attr = $action->attributes->{CaptureArgs}) { |
3f91cb25 |
228 | my $capture_count = $capture_attr->[0] || 0; |
f505df49 |
229 | |
230 | # Short-circuit if not enough remaining parts |
3f91cb25 |
231 | next TRY_ACTION unless @parts >= $capture_count; |
f505df49 |
232 | |
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233 | my @captures; |
234 | my @parts = @parts; # localise |
7a7ac23c |
235 | |
1c34f703 |
236 | # strip CaptureArgs into list |
3f91cb25 |
237 | push(@captures, splice(@parts, 0, $capture_count)); |
7a7ac23c |
238 | |
1279064a |
239 | # check if the action may fit, depending on a given test by the app |
240 | if ($action->can('match_captures')) { next TRY_ACTION unless $action->match_captures($c, \@captures) } |
241 | |
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242 | # try the remaining parts against children of this action |
0c78acb6 |
243 | my ($actions, $captures, $action_parts, $n_pathparts) = $self->recurse_match( |
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244 | $c, '/'.$action->reverse, \@parts |
245 | ); |
2f381252 |
246 | # No best action currently |
247 | # OR The action has less parts |
248 | # OR The action has equal parts but less captured data (ergo more defined) |
249 | if ($actions && |
250 | (!$best_action || |
f4dbb497 |
251 | $#$action_parts < $#{$best_action->{parts}} || |
2f381252 |
252 | ($#$action_parts == $#{$best_action->{parts}} && |
0c78acb6 |
253 | $#$captures < $#{$best_action->{captures}} && |
254 | $n_pathparts > $best_action->{n_pathparts}))) { |
255 | my @pathparts = split /\//, $action->attributes->{PathPart}->[0]; |
6b495723 |
256 | $best_action = { |
257 | actions => [ $action, @$actions ], |
258 | captures=> [ @captures, @$captures ], |
0c78acb6 |
259 | parts => $action_parts, |
260 | n_pathparts => scalar(@pathparts) + $n_pathparts, |
261 | }; |
6b495723 |
262 | } |
263 | } |
264 | else { |
7a7ac23c |
265 | { |
266 | local $c->req->{arguments} = [ @{$c->req->args}, @parts ]; |
267 | next TRY_ACTION unless $action->match($c); |
268 | } |
5c6d829d |
269 | my $args_attr = $action->attributes->{Args}->[0]; |
0c78acb6 |
270 | my @pathparts = split /\//, $action->attributes->{PathPart}->[0]; |
953c176d |
271 | # No best action currently |
272 | # OR This one matches with fewer parts left than the current best action, |
273 | # And therefore is a better match |
b0ad47c1 |
274 | # OR No parts and this expects 0 |
953c176d |
275 | # The current best action might also be Args(0), |
276 | # but we couldn't chose between then anyway so we'll take the last seen |
277 | |
278 | if (!$best_action || |
279 | @parts < @{$best_action->{parts}} || |
a53e36d1 |
280 | (!@parts && defined($args_attr) && $args_attr eq "0")){ |
6b495723 |
281 | $best_action = { |
282 | actions => [ $action ], |
283 | captures=> [], |
0c78acb6 |
284 | parts => \@parts, |
285 | n_pathparts => scalar(@pathparts), |
286 | }; |
953c176d |
287 | } |
141459fa |
288 | } |
289 | } |
290 | } |
0c78acb6 |
291 | return @$best_action{qw/actions captures parts n_pathparts/} if $best_action; |
141459fa |
292 | return (); |
293 | } |
294 | |
295 | =head2 $self->register( $c, $action ) |
296 | |
05a90578 |
297 | Calls register_path for every Path attribute for the given $action. |
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298 | |
299 | =cut |
300 | |
2e29aec2 |
301 | sub _check_args_attr { |
302 | my ( $self, $action, $name ) = @_; |
303 | |
304 | return unless exists $action->attributes->{$name}; |
305 | |
306 | if (@{$action->attributes->{$name}} > 1) { |
307 | Catalyst::Exception->throw( |
308 | "Multiple $name attributes not supported registering " . $action->reverse() |
309 | ); |
310 | } |
311 | my $args = $action->attributes->{$name}->[0]; |
312 | if (defined($args) and not ( |
313 | Scalar::Util::looks_like_number($args) and |
2782bef2 |
314 | int($args) == $args and $args >= 0 |
2e29aec2 |
315 | )) { |
316 | require Data::Dumper; |
317 | local $Data::Dumper::Terse = 1; |
318 | local $Data::Dumper::Indent = 0; |
319 | $args = Data::Dumper::Dumper($args); |
320 | Catalyst::Exception->throw( |
321 | "Invalid $name($args) for action " . $action->reverse() . |
322 | " (use '$name' or '$name(<number>)')" |
323 | ); |
324 | } |
325 | } |
326 | |
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327 | sub register { |
328 | my ( $self, $c, $action ) = @_; |
329 | |
1dc8af44 |
330 | my @chained_attr = @{ $action->attributes->{Chained} || [] }; |
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331 | |
1dc8af44 |
332 | return 0 unless @chained_attr; |
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333 | |
2f381252 |
334 | if (@chained_attr > 1) { |
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335 | Catalyst::Exception->throw( |
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336 | "Multiple Chained attributes not supported registering ${action}" |
141459fa |
337 | ); |
338 | } |
13c6b4cc |
339 | my $chained_to = $chained_attr[0]; |
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340 | |
13c6b4cc |
341 | Catalyst::Exception->throw( |
342 | "Actions cannot chain to themselves registering /${action}" |
343 | ) if ($chained_to eq '/' . $action); |
344 | |
345 | my $children = ($self->_children_of->{ $chained_to } ||= {}); |
141459fa |
346 | |
347 | my @path_part = @{ $action->attributes->{PathPart} || [] }; |
348 | |
09461385 |
349 | my $part = $action->name; |
141459fa |
350 | |
09461385 |
351 | if (@path_part == 1 && defined $path_part[0]) { |
352 | $part = $path_part[0]; |
141459fa |
353 | } elsif (@path_part > 1) { |
354 | Catalyst::Exception->throw( |
f3414019 |
355 | "Multiple PathPart attributes not supported registering " . $action->reverse() |
141459fa |
356 | ); |
357 | } |
358 | |
8a6a6581 |
359 | if ($part =~ m(^/)) { |
360 | Catalyst::Exception->throw( |
f3414019 |
361 | "Absolute parameters to PathPart not allowed registering " . $action->reverse() |
8a6a6581 |
362 | ); |
363 | } |
364 | |
77771155 |
365 | $action->attributes->{PathPart} = [ $part ]; |
792b40ac |
366 | |
141459fa |
367 | unshift(@{ $children->{$part} ||= [] }, $action); |
368 | |
be5cb4e4 |
369 | $self->_actions->{'/'.$action->reverse} = $action; |
792b40ac |
370 | |
2e29aec2 |
371 | foreach my $name (qw(Args CaptureArgs)) { |
372 | $self->_check_args_attr($action, $name); |
373 | } |
374 | |
375 | if (exists $action->attributes->{Args} and exists $action->attributes->{CaptureArgs}) { |
376 | Catalyst::Exception->throw( |
bc71493a |
377 | "Combining Args and CaptureArgs attributes not supported registering " . |
378 | $action->reverse() |
2e29aec2 |
379 | ); |
dd97c1ac |
380 | } |
381 | |
1c34f703 |
382 | unless ($action->attributes->{CaptureArgs}) { |
be5cb4e4 |
383 | unshift(@{ $self->_endpoints }, $action); |
792b40ac |
384 | } |
385 | |
386 | return 1; |
141459fa |
387 | } |
388 | |
389 | =head2 $self->uri_for_action($action, $captures) |
390 | |
05a90578 |
391 | Get the URI part for the action, using C<$captures> to fill |
392 | the capturing parts. |
141459fa |
393 | |
394 | =cut |
395 | |
396 | sub uri_for_action { |
397 | my ( $self, $action, $captures ) = @_; |
398 | |
5882c86e |
399 | return undef unless ($action->attributes->{Chained} |
8b13f357 |
400 | && !$action->attributes->{CaptureArgs}); |
792b40ac |
401 | |
402 | my @parts = (); |
403 | my @captures = @$captures; |
404 | my $parent = "DUMMY"; |
405 | my $curr = $action; |
406 | while ($curr) { |
1c34f703 |
407 | if (my $cap = $curr->attributes->{CaptureArgs}) { |
84ac8ab9 |
408 | return undef unless @captures >= ($cap->[0]||0); # not enough captures |
8b13f357 |
409 | if ($cap->[0]) { |
f9155483 |
410 | unshift(@parts, splice(@captures, -$cap->[0])); |
8b13f357 |
411 | } |
792b40ac |
412 | } |
77771155 |
413 | if (my $pp = $curr->attributes->{PathPart}) { |
792b40ac |
414 | unshift(@parts, $pp->[0]) |
8b13f357 |
415 | if (defined($pp->[0]) && length($pp->[0])); |
792b40ac |
416 | } |
5882c86e |
417 | $parent = $curr->attributes->{Chained}->[0]; |
be5cb4e4 |
418 | $curr = $self->_actions->{$parent}; |
141459fa |
419 | } |
792b40ac |
420 | |
421 | return undef unless $parent eq '/'; # fail for dangling action |
422 | |
423 | return undef if @captures; # fail for too many captures |
424 | |
425 | return join('/', '', @parts); |
59d5a638 |
426 | |
141459fa |
427 | } |
428 | |
ae0e35ee |
429 | =head2 $c->expand_action($action) |
430 | |
b0ad47c1 |
431 | Return a list of actions that represents a chained action. See |
ae0e35ee |
432 | L<Catalyst::Dispatcher> for more info. You probably want to |
433 | use the expand_action it provides rather than this directly. |
434 | |
435 | =cut |
436 | |
52f71256 |
437 | sub expand_action { |
438 | my ($self, $action) = @_; |
439 | |
440 | return unless $action->attributes && $action->attributes->{Chained}; |
441 | |
442 | my @chain; |
443 | my $curr = $action; |
444 | |
445 | while ($curr) { |
446 | push @chain, $curr; |
447 | my $parent = $curr->attributes->{Chained}->[0]; |
448 | $curr = $self->_actions->{$parent}; |
449 | } |
450 | |
451 | return Catalyst::ActionChain->from_chain([reverse @chain]); |
452 | } |
453 | |
e5ecd5bc |
454 | __PACKAGE__->meta->make_immutable; |
f4de8c99 |
455 | 1; |
e5ecd5bc |
456 | |
05a90578 |
457 | =head1 USAGE |
458 | |
459 | =head2 Introduction |
460 | |
461 | The C<Chained> attribute allows you to chain public path parts together |
67869327 |
462 | by their private names. A chain part's path can be specified with |
463 | C<PathPart> and can be declared to expect an arbitrary number of |
464 | arguments. The endpoint of the chain specifies how many arguments it |
465 | gets through the C<Args> attribute. C<:Args(0)> would be none at all, |
466 | C<:Args> without an integer would be unlimited. The path parts that |
467 | aren't endpoints are using C<CaptureArgs> to specify how many parameters |
468 | they expect to receive. As an example setup: |
05a90578 |
469 | |
470 | package MyApp::Controller::Greeting; |
471 | use base qw/ Catalyst::Controller /; |
472 | |
473 | # this is the beginning of our chain |
474 | sub hello : PathPart('hello') Chained('/') CaptureArgs(1) { |
475 | my ( $self, $c, $integer ) = @_; |
476 | $c->stash->{ message } = "Hello "; |
477 | $c->stash->{ arg_sum } = $integer; |
478 | } |
479 | |
480 | # this is our endpoint, because it has no :CaptureArgs |
481 | sub world : PathPart('world') Chained('hello') Args(1) { |
482 | my ( $self, $c, $integer ) = @_; |
483 | $c->stash->{ message } .= "World!"; |
484 | $c->stash->{ arg_sum } += $integer; |
485 | |
486 | $c->response->body( join "<br/>\n" => |
487 | $c->stash->{ message }, $c->stash->{ arg_sum } ); |
488 | } |
489 | |
490 | The debug output provides a separate table for chained actions, showing |
67869327 |
491 | the whole chain as it would match and the actions it contains. Here's an |
492 | example of the startup output with our actions above: |
05a90578 |
493 | |
494 | ... |
495 | [debug] Loaded Path Part actions: |
496 | .-----------------------+------------------------------. |
497 | | Path Spec | Private | |
498 | +-----------------------+------------------------------+ |
499 | | /hello/*/world/* | /greeting/hello (1) | |
500 | | | => /greeting/world | |
501 | '-----------------------+------------------------------' |
502 | ... |
503 | |
67869327 |
504 | As you can see, Catalyst only deals with chains as whole paths and |
505 | builds one for each endpoint, which are the actions with C<:Chained> but |
506 | without C<:CaptureArgs>. |
05a90578 |
507 | |
508 | Let's assume this application gets a request at the path |
67869327 |
509 | C</hello/23/world/12>. What happens then? First, Catalyst will dispatch |
510 | to the C<hello> action and pass the value C<23> as an argument to it |
511 | after the context. It does so because we have previously used |
512 | C<:CaptureArgs(1)> to declare that it has one path part after itself as |
513 | its argument. We told Catalyst that this is the beginning of the chain |
514 | by specifying C<:Chained('/')>. Also note that instead of saying |
515 | C<:PathPart('hello')> we could also just have said C<:PathPart>, as it |
516 | defaults to the name of the action. |
05a90578 |
517 | |
518 | After C<hello> has run, Catalyst goes on to dispatch to the C<world> |
67869327 |
519 | action. This is the last action to be called: Catalyst knows this is an |
520 | endpoint because we did not specify a C<:CaptureArgs> |
521 | attribute. Nevertheless we specify that this action expects an argument, |
522 | but at this point we're using C<:Args(1)> to do that. We could also have |
523 | said C<:Args> or left it out altogether, which would mean this action |
524 | would get all arguments that are there. This action's C<:Chained> |
525 | attribute says C<hello> and tells Catalyst that the C<hello> action in |
526 | the current controller is its parent. |
05a90578 |
527 | |
528 | With this we have built a chain consisting of two public path parts. |
67869327 |
529 | C<hello> captures one part of the path as its argument, and also |
530 | specifies the path root as its parent. So this part is |
531 | C</hello/$arg>. The next part is the endpoint C<world>, expecting one |
532 | argument. It sums up to the path part C<world/$arg>. This leads to a |
533 | complete chain of C</hello/$arg/world/$arg> which is matched against the |
534 | requested paths. |
535 | |
536 | This example application would, if run and called by e.g. |
537 | C</hello/23/world/12>, set the stash value C<message> to "Hello" and the |
538 | value C<arg_sum> to "23". The C<world> action would then append "World!" |
539 | to C<message> and add C<12> to the stash's C<arg_sum> value. For the |
540 | sake of simplicity no view is shown. Instead we just put the values of |
541 | the stash into our body. So the output would look like: |
05a90578 |
542 | |
543 | Hello World! |
544 | 35 |
545 | |
67869327 |
546 | And our test server would have given us this debugging output for the |
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547 | request: |
548 | |
549 | ... |
550 | [debug] "GET" request for "hello/23/world/12" from "127.0.0.1" |
551 | [debug] Path is "/greeting/world" |
552 | [debug] Arguments are "12" |
553 | [info] Request took 0.164113s (6.093/s) |
554 | .------------------------------------------+-----------. |
555 | | Action | Time | |
556 | +------------------------------------------+-----------+ |
557 | | /greeting/hello | 0.000029s | |
558 | | /greeting/world | 0.000024s | |
559 | '------------------------------------------+-----------' |
560 | ... |
561 | |
67869327 |
562 | What would be common uses of this dispatch technique? It gives the |
563 | possibility to split up logic that contains steps that each depend on |
564 | each other. An example would be, for example, a wiki path like |
05a90578 |
565 | C</wiki/FooBarPage/rev/23/view>. This chain can be easily built with |
566 | these actions: |
567 | |
568 | sub wiki : PathPart('wiki') Chained('/') CaptureArgs(1) { |
569 | my ( $self, $c, $page_name ) = @_; |
570 | # load the page named $page_name and put the object |
571 | # into the stash |
572 | } |
573 | |
574 | sub rev : PathPart('rev') Chained('wiki') CaptureArgs(1) { |
575 | my ( $self, $c, $revision_id ) = @_; |
67869327 |
576 | # use the page object in the stash to get at its |
05a90578 |
577 | # revision with number $revision_id |
578 | } |
579 | |
580 | sub view : PathPart Chained('rev') Args(0) { |
581 | my ( $self, $c ) = @_; |
67869327 |
582 | # display the revision in our stash. Another option |
05a90578 |
583 | # would be to forward a compatible object to the action |
584 | # that displays the default wiki pages, unless we want |
585 | # a different interface here, for example restore |
586 | # functionality. |
587 | } |
588 | |
67869327 |
589 | It would now be possible to add other endpoints, for example C<restore> |
590 | to restore this specific revision as the current state. |
05a90578 |
591 | |
67869327 |
592 | You don't have to put all the chained actions in one controller. The |
593 | specification of the parent through C<:Chained> also takes an absolute |
594 | action path as its argument. Just specify it with a leading C</>. |
05a90578 |
595 | |
596 | If you want, for example, to have actions for the public paths |
67869327 |
597 | C</foo/12/edit> and C</foo/12>, just specify two actions with |
05a90578 |
598 | C<:PathPart('foo')> and C<:Chained('/')>. The handler for the former |
67869327 |
599 | path needs a C<:CaptureArgs(1)> attribute and a endpoint with |
05a90578 |
600 | C<:PathPart('edit')> and C<:Chained('foo')>. For the latter path give |
601 | the action just a C<:Args(1)> to mark it as endpoint. This sums up to |
602 | this debugging output: |
603 | |
604 | ... |
605 | [debug] Loaded Path Part actions: |
606 | .-----------------------+------------------------------. |
607 | | Path Spec | Private | |
608 | +-----------------------+------------------------------+ |
609 | | /foo/* | /controller/foo_view | |
610 | | /foo/*/edit | /controller/foo_load (1) | |
611 | | | => /controller/edit | |
612 | '-----------------------+------------------------------' |
613 | ... |
614 | |
b0ad47c1 |
615 | Here's a more detailed specification of the attributes belonging to |
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616 | C<:Chained>: |
617 | |
618 | =head2 Attributes |
619 | |
620 | =over 8 |
621 | |
622 | =item PathPart |
623 | |
624 | Sets the name of this part of the chain. If it is specified without |
625 | arguments, it takes the name of the action as default. So basically |
626 | C<sub foo :PathPart> and C<sub foo :PathPart('foo')> are identical. |
627 | This can also contain slashes to bind to a deeper level. An action |
628 | with C<sub bar :PathPart('foo/bar') :Chained('/')> would bind to |
629 | C</foo/bar/...>. If you don't specify C<:PathPart> it has the same |
630 | effect as using C<:PathPart>, it would default to the action name. |
631 | |
d21a2b27 |
632 | =item PathPrefix |
633 | |
634 | Sets PathPart to the path_prefix of the current controller. |
635 | |
05a90578 |
636 | =item Chained |
637 | |
638 | Has to be specified for every child in the chain. Possible values are |
d21a2b27 |
639 | absolute and relative private action paths or a single slash C</> to |
640 | tell Catalyst that this is the root of a chain. The attribute |
641 | C<:Chained> without arguments also defaults to the C</> behavior. |
642 | Relative action paths may use C<../> to refer to actions in parent |
643 | controllers. |
05a90578 |
644 | |
67869327 |
645 | Because you can specify an absolute path to the parent action, it |
646 | doesn't matter to Catalyst where that parent is located. So, if your |
647 | design requests it, you can redispatch a chain through any controller or |
648 | namespace you want. |
05a90578 |
649 | |
650 | Another interesting possibility gives C<:Chained('.')>, which chains |
67869327 |
651 | itself to an action with the path of the current controller's namespace. |
05a90578 |
652 | For example: |
653 | |
654 | # in MyApp::Controller::Foo |
655 | sub bar : Chained CaptureArgs(1) { ... } |
656 | |
657 | # in MyApp::Controller::Foo::Bar |
658 | sub baz : Chained('.') Args(1) { ... } |
659 | |
660 | This builds up a chain like C</bar/*/baz/*>. The specification of C<.> |
67869327 |
661 | as the argument to Chained here chains the C<baz> action to an action |
662 | with the path of the current controller namespace, namely |
663 | C</foo/bar>. That action chains directly to C</>, so the C</bar/*/baz/*> |
664 | chain comes out as the end product. |
05a90578 |
665 | |
d21a2b27 |
666 | =item ChainedParent |
667 | |
668 | Chains an action to another action with the same name in the parent |
669 | controller. For Example: |
670 | |
671 | # in MyApp::Controller::Foo |
672 | sub bar : Chained CaptureArgs(1) { ... } |
673 | |
674 | # in MyApp::Controller::Foo::Moo |
675 | sub bar : ChainedParent Args(1) { ... } |
676 | |
677 | This builds a chain like C</bar/*/bar/*>. |
678 | |
05a90578 |
679 | =item CaptureArgs |
680 | |
67869327 |
681 | Must be specified for every part of the chain that is not an |
05a90578 |
682 | endpoint. With this attribute Catalyst knows how many of the following |
67869327 |
683 | parts of the path (separated by C</>) this action wants to capture as |
684 | its arguments. If it doesn't expect any, just specify |
685 | C<:CaptureArgs(0)>. The captures get passed to the action's C<@_> right |
686 | after the context, but you can also find them as array references in |
05a90578 |
687 | C<$c-E<gt>request-E<gt>captures-E<gt>[$level]>. The C<$level> is the |
688 | level of the action in the chain that captured the parts of the path. |
689 | |
67869327 |
690 | An action that is part of a chain (that is, one that has a C<:Chained> |
691 | attribute) but has no C<:CaptureArgs> attribute is treated by Catalyst |
692 | as a chain end. |
05a90578 |
693 | |
694 | =item Args |
695 | |
696 | By default, endpoints receive the rest of the arguments in the path. You |
697 | can tell Catalyst through C<:Args> explicitly how many arguments your |
698 | endpoint expects, just like you can with C<:CaptureArgs>. Note that this |
67869327 |
699 | also affects whether this chain is invoked on a request. A chain with an |
05a90578 |
700 | endpoint specifying one argument will only match if exactly one argument |
701 | exists in the path. |
702 | |
703 | You can specify an exact number of arguments like C<:Args(3)>, including |
704 | C<0>. If you just say C<:Args> without any arguments, it is the same as |
67869327 |
705 | leaving it out altogether: The chain is matched regardless of the number |
05a90578 |
706 | of path parts after the endpoint. |
707 | |
67869327 |
708 | Just as with C<:CaptureArgs>, the arguments get passed to the action in |
05a90578 |
709 | C<@_> after the context object. They can also be reached through |
710 | C<$c-E<gt>request-E<gt>arguments>. |
711 | |
712 | =back |
713 | |
67869327 |
714 | =head2 Auto actions, dispatching and forwarding |
05a90578 |
715 | |
716 | Note that the list of C<auto> actions called depends on the private path |
67869327 |
717 | of the endpoint of the chain, not on the chained actions way. The |
718 | C<auto> actions will be run before the chain dispatching begins. In |
719 | every other aspect, C<auto> actions behave as documented. |
05a90578 |
720 | |
64111aca |
721 | The C<forward>ing to other actions does just what you would expect. i.e. |
e1207438 |
722 | only the target action is run. The actions that that action is chained |
723 | to are not run. |
724 | If you C<detach> out of a chain, the rest of the chain will not get |
725 | called after the C<detach>. |
05a90578 |
726 | |
22faeff5 |
727 | =head2 match_captures |
728 | |
729 | A method which can optionally be implemented by actions to |
730 | stop chain matching. |
731 | |
732 | See L<Catalyst::Action> for further details. |
733 | |
2f381252 |
734 | =head1 AUTHORS |
141459fa |
735 | |
2f381252 |
736 | Catalyst Contributors, see Catalyst.pm |
141459fa |
737 | |
738 | =head1 COPYRIGHT |
739 | |
536bee89 |
740 | This library is free software. You can redistribute it and/or modify it under |
141459fa |
741 | the same terms as Perl itself. |
742 | |
743 | =cut |
744 | |
745 | 1; |