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