Commit | Line | Data |
9e447f9d |
1 | #!/usr/bin/perl |
2 | |
3 | package Catalyst::Plugin::Session; |
4 | use base qw/Class::Accessor::Fast/; |
5 | |
6 | use strict; |
7 | use warnings; |
8 | |
9 | use NEXT; |
10 | use Catalyst::Exception (); |
9a9252c2 |
11 | use Digest (); |
12 | use overload (); |
d44bc687 |
13 | use Object::Signature (); |
9e447f9d |
14 | |
5d8cc4c7 |
15 | our $VERSION = "0.05"; |
37160715 |
16 | |
ab634fee |
17 | my @session_data_accessors; # used in delete_session |
9e447f9d |
18 | BEGIN { |
4207ce8d |
19 | __PACKAGE__->mk_accessors( |
ab634fee |
20 | "_session_delete_reason", |
21 | @session_data_accessors = qw/ |
4207ce8d |
22 | _sessionid |
23 | _session |
24 | _session_expires |
25 | _session_data_sig |
4207ce8d |
26 | _flash |
f4d79f85 |
27 | _flash_keep_keys |
28 | _flash_key_hashes |
1dbf4cd5 |
29 | _tried_loading_session_id |
30 | _tried_loading_session_data |
31 | _tried_loading_session_expires |
32 | _tried_loading_flash_data |
4207ce8d |
33 | / |
34 | ); |
9e447f9d |
35 | } |
36 | |
37 | sub setup { |
9a9252c2 |
38 | my $c = shift; |
39 | |
40 | $c->NEXT::setup(@_); |
41 | |
42 | $c->check_session_plugin_requirements; |
43 | $c->setup_session; |
44 | |
45 | return $c; |
9e447f9d |
46 | } |
47 | |
48 | sub check_session_plugin_requirements { |
9a9252c2 |
49 | my $c = shift; |
9e447f9d |
50 | |
9a9252c2 |
51 | unless ( $c->isa("Catalyst::Plugin::Session::State") |
52 | && $c->isa("Catalyst::Plugin::Session::Store") ) |
53 | { |
54 | my $err = |
55 | ( "The Session plugin requires both Session::State " |
56 | . "and Session::Store plugins to be used as well." ); |
9e447f9d |
57 | |
9a9252c2 |
58 | $c->log->fatal($err); |
59 | Catalyst::Exception->throw($err); |
60 | } |
9e447f9d |
61 | } |
62 | |
63 | sub setup_session { |
9a9252c2 |
64 | my $c = shift; |
9e447f9d |
65 | |
9a9252c2 |
66 | my $cfg = ( $c->config->{session} ||= {} ); |
9e447f9d |
67 | |
9a9252c2 |
68 | %$cfg = ( |
69 | expires => 7200, |
70 | verify_address => 1, |
71 | %$cfg, |
72 | ); |
9e447f9d |
73 | |
9a9252c2 |
74 | $c->NEXT::setup_session(); |
9e447f9d |
75 | } |
76 | |
19c130c2 |
77 | sub prepare_action { |
78 | my $c = shift; |
79 | |
4207ce8d |
80 | if ( $c->config->{session}{flash_to_stash} |
e5b2372a |
81 | and $c->sessionid |
4207ce8d |
82 | and my $flash_data = $c->flash ) |
83 | { |
19c130c2 |
84 | @{ $c->stash }{ keys %$flash_data } = values %$flash_data; |
85 | } |
86 | |
87 | $c->NEXT::prepare_action(@_); |
88 | } |
89 | |
9e447f9d |
90 | sub finalize { |
9a9252c2 |
91 | my $c = shift; |
9e447f9d |
92 | |
1dbf4cd5 |
93 | $c->_save_session_expires; |
9b0fa2a6 |
94 | $c->_save_session; |
95 | $c->_save_flash; |
96 | |
97 | $c->NEXT::finalize(@_); |
98 | } |
99 | |
1dbf4cd5 |
100 | sub _save_session_expires { |
9b0fa2a6 |
101 | my $c = shift; |
4207ce8d |
102 | |
1dbf4cd5 |
103 | if ( defined(my $expires = $c->_session_expires) ) { |
104 | my $sid = $c->sessionid; |
105 | $c->store_session_data( "expires:$sid" => $expires ); |
9e447f9d |
106 | |
1dbf4cd5 |
107 | $c->_session_expires(undef); |
108 | $c->_tried_loading_session_expires(undef); |
109 | } |
110 | } |
6687905d |
111 | |
1dbf4cd5 |
112 | sub _save_session { |
113 | my $c = shift; |
7a02371f |
114 | |
1dbf4cd5 |
115 | if ( my $session_data = $c->_session ) { |
d44bc687 |
116 | |
1dbf4cd5 |
117 | no warnings 'uninitialized'; |
118 | if ( Object::Signature::signature($session_data) ne |
119 | $c->_session_data_sig ) |
120 | { |
121 | $session_data->{__updated} = time(); |
122 | my $sid = $c->sessionid; |
123 | $c->store_session_data( "session:$sid" => $session_data ); |
ea972e9a |
124 | } |
1dbf4cd5 |
125 | |
126 | $c->_session(undef); |
127 | $c->_tried_loading_session_data(undef); |
9a9252c2 |
128 | } |
9b0fa2a6 |
129 | } |
9a9252c2 |
130 | |
9b0fa2a6 |
131 | sub _save_flash { |
132 | my $c = shift; |
133 | |
1dbf4cd5 |
134 | if ( my $flash_data = $c->_flash ) { |
4207ce8d |
135 | |
1dbf4cd5 |
136 | my $hashes = $c->_flash_key_hashes || {}; |
137 | my $keep = $c->_flash_keep_keys || {}; |
138 | foreach my $key ( keys %$hashes ) { |
139 | if ( !exists $keep->{$key} and Object::Signature::signature( \$flash_data->{$key} ) eq $hashes->{$key} ) { |
140 | delete $flash_data->{$key}; |
23fbca00 |
141 | } |
ea972e9a |
142 | } |
1dbf4cd5 |
143 | |
144 | my $sid = $c->sessionid; |
145 | |
146 | if (%$flash_data) { |
147 | $c->store_session_data( "flash:$sid", $flash_data ); |
148 | } |
149 | else { |
150 | $c->delete_session_data("flash:$sid"); |
151 | } |
152 | |
153 | $c->_flash(undef); |
154 | $c->_tried_loading_flash_data(undef); |
9b0fa2a6 |
155 | } |
9e447f9d |
156 | } |
157 | |
e5b2372a |
158 | sub _load_session_expires { |
159 | my $c = shift; |
1dbf4cd5 |
160 | return if $c->_tried_loading_session_expires; |
161 | $c->_tried_loading_session_expires(1); |
e5b2372a |
162 | |
163 | if ( my $sid = $c->sessionid ) { |
164 | my $expires = $c->get_session_data("expires:$sid") || 0; |
165 | |
166 | if ( $expires >= time() ) { |
167 | return $c->extend_session_expires( $expires ); |
168 | } else { |
169 | $c->delete_session( "session expired" ); |
170 | return 0; |
171 | } |
e5b2372a |
172 | } |
1dbf4cd5 |
173 | |
174 | return; |
e5b2372a |
175 | } |
176 | |
b7acf64e |
177 | sub _load_session { |
178 | my $c = shift; |
1dbf4cd5 |
179 | return if $c->_tried_loading_session_data; |
180 | $c->_tried_loading_session_data(1); |
b7acf64e |
181 | |
e5b2372a |
182 | if ( my $sid = $c->sessionid ) { |
6687905d |
183 | if ( $c->session_expires ) { # > 0 |
0974ac06 |
184 | |
2e412459 |
185 | my $session_data = $c->get_session_data("session:$sid") || return; |
6687905d |
186 | $c->_session($session_data); |
3f182468 |
187 | |
6687905d |
188 | no warnings 'uninitialized'; # ne __address |
189 | if ( $c->config->{session}{verify_address} |
190 | && $session_data->{__address} ne $c->request->address ) |
191 | { |
192 | $c->log->warn( |
193 | "Deleting session $sid due to address mismatch (" |
194 | . $session_data->{__address} . " != " |
47ca362e |
195 | . $c->request->address . ")" |
6687905d |
196 | ); |
197 | $c->delete_session("address mismatch"); |
198 | return; |
199 | } |
4207ce8d |
200 | |
6687905d |
201 | $c->log->debug(qq/Restored session "$sid"/) if $c->debug; |
168d6819 |
202 | $c->_session_data_sig( Object::Signature::signature($session_data) ) if $session_data; |
6687905d |
203 | $c->_expire_session_keys; |
4207ce8d |
204 | |
6687905d |
205 | return $session_data; |
3f182468 |
206 | } |
9a9252c2 |
207 | } |
29d15411 |
208 | |
4207ce8d |
209 | return; |
b7acf64e |
210 | } |
9a9252c2 |
211 | |
9b0fa2a6 |
212 | sub _load_flash { |
213 | my $c = shift; |
1dbf4cd5 |
214 | return if $c->_tried_loading_flash_data; |
215 | $c->_tried_loading_flash_data(1); |
9b0fa2a6 |
216 | |
e5b2372a |
217 | if ( my $sid = $c->sessionid ) { |
4207ce8d |
218 | if ( my $flash_data = $c->_flash |
219 | || $c->_flash( $c->get_session_data("flash:$sid") ) ) |
220 | { |
f4d79f85 |
221 | $c->_flash_key_hashes({ map { $_ => Object::Signature::signature( \$flash_data->{$_} ) } keys %$flash_data }); |
e5b2372a |
222 | |
9b0fa2a6 |
223 | return $flash_data; |
224 | } |
225 | } |
226 | |
1dbf4cd5 |
227 | return; |
9b0fa2a6 |
228 | } |
229 | |
d44bc687 |
230 | sub _expire_session_keys { |
b7acf64e |
231 | my ( $c, $data ) = @_; |
232 | |
233 | my $now = time; |
234 | |
e5b2372a |
235 | my $expire_times = ( $data || $c->_session || {} )->{__expire_keys} || {}; |
236 | foreach my $key ( grep { $expire_times->{$_} < $now } keys %$expire_times ) { |
b7acf64e |
237 | delete $c->_session->{$key}; |
e5b2372a |
238 | delete $expire_times->{$key}; |
b7acf64e |
239 | } |
9e447f9d |
240 | } |
241 | |
242 | sub delete_session { |
9a9252c2 |
243 | my ( $c, $msg ) = @_; |
9e447f9d |
244 | |
9a9252c2 |
245 | # delete the session data |
e5b2372a |
246 | my $sid = $c->sessionid || return; |
4207ce8d |
247 | $c->delete_session_data("${_}:${sid}") for qw/session expires flash/; |
9e447f9d |
248 | |
e5b2372a |
249 | $c->delete_session_id; |
250 | |
9a9252c2 |
251 | # reset the values in the context object |
ab634fee |
252 | # see the BEGIN block |
253 | $c->$_(undef) for @session_data_accessors; |
6687905d |
254 | |
29d15411 |
255 | $c->_session_delete_reason($msg); |
256 | } |
257 | |
258 | sub session_delete_reason { |
259 | my $c = shift; |
260 | |
e5b2372a |
261 | $c->session_is_valid; # check that it was loaded |
29d15411 |
262 | |
4207ce8d |
263 | $c->_session_delete_reason(@_); |
9e447f9d |
264 | } |
265 | |
6687905d |
266 | sub session_expires { |
e5b2372a |
267 | my $c = shift; |
6687905d |
268 | |
e5b2372a |
269 | if ( defined( my $expires = $c->_session_expires ) ) { |
270 | return $expires; |
1dbf4cd5 |
271 | } elsif ( defined( $expires = $c->_load_session_expires ) ) { |
272 | $c->_session_expires($expires); |
273 | return $expires; |
e5b2372a |
274 | } else { |
1dbf4cd5 |
275 | return 0; |
e5b2372a |
276 | } |
277 | } |
6687905d |
278 | |
e5b2372a |
279 | sub extend_session_expires { |
280 | my ( $c, $expires ) = @_; |
e5b2372a |
281 | $c->_session_expires( my $updated = $c->calculate_extended_session_expires( $expires ) ); |
4c79feb6 |
282 | $c->extend_session_id( $c->sessionid, $updated ); |
e5b2372a |
283 | return $updated; |
284 | } |
6687905d |
285 | |
e5b2372a |
286 | sub calculate_initial_session_expires { |
287 | my $c = shift; |
288 | return ( time() + $c->config->{session}{expires} ); |
289 | } |
290 | |
291 | sub calculate_extended_session_expires { |
292 | my ( $c, $prev ) = @_; |
293 | $c->calculate_initial_session_expires; |
294 | } |
295 | |
296 | sub reset_session_expires { |
297 | my ( $c, $sid ) = @_; |
298 | $c->_session_expires( my $exp = $c->calculate_initial_session_expires ); |
299 | $exp; |
6687905d |
300 | } |
301 | |
0974ac06 |
302 | sub sessionid { |
4207ce8d |
303 | my $c = shift; |
e5b2372a |
304 | |
1dbf4cd5 |
305 | return $c->_sessionid || $c->_load_sessionid; |
306 | } |
307 | |
308 | sub _load_sessionid { |
309 | my $c = shift; |
310 | return if $c->_tried_loading_session_id; |
311 | $c->_tried_loading_session_id(1); |
312 | |
313 | if ( defined( my $sid = $c->get_session_id ) ) { |
314 | if ( $c->validate_session_id($sid) ) { |
315 | $c->_sessionid( $sid ); |
316 | return $sid; |
317 | } else { |
318 | my $err = "Tried to set invalid session ID '$sid'"; |
319 | $c->log->error($err); |
320 | Catalyst::Exception->throw($err); |
4207ce8d |
321 | } |
322 | } |
1dbf4cd5 |
323 | |
324 | return; |
e5b2372a |
325 | } |
326 | |
327 | sub session_is_valid { |
328 | my $c = shift; |
4207ce8d |
329 | |
1dbf4cd5 |
330 | $c->_load_session; # check expiry and also __address, etc |
4207ce8d |
331 | |
e5b2372a |
332 | if ( $c->_session ) { |
333 | return 1; |
334 | } else { |
335 | return; |
336 | } |
0974ac06 |
337 | } |
338 | |
339 | sub validate_session_id { |
4207ce8d |
340 | my ( $c, $sid ) = @_; |
0974ac06 |
341 | |
4207ce8d |
342 | $sid and $sid =~ /^[a-f\d]+$/i; |
0974ac06 |
343 | } |
344 | |
9e447f9d |
345 | sub session { |
9a9252c2 |
346 | my $c = shift; |
9e447f9d |
347 | |
29d15411 |
348 | $c->_session || $c->_load_session || do { |
1dbf4cd5 |
349 | $c->create_session_id_if_needed; |
29d15411 |
350 | $c->initialize_session_data; |
4207ce8d |
351 | }; |
9e447f9d |
352 | } |
353 | |
f4d79f85 |
354 | sub keep_flash { |
355 | my ( $c, @keys ) = @_; |
2e412459 |
356 | my $href = $c->_flash_keep_keys || $c->_flash_keep_keys({}); |
357 | (@{$href}{@keys}) = ((undef) x @keys); |
f4d79f85 |
358 | } |
359 | |
873f7011 |
360 | sub flash { |
361 | my $c = shift; |
78476ce0 |
362 | $c->_flash || $c->_load_flash || do { |
1dbf4cd5 |
363 | $c->create_session_id_if_needed; |
78476ce0 |
364 | $c->_flash( {} ); |
1dbf4cd5 |
365 | } |
873f7011 |
366 | } |
367 | |
b7acf64e |
368 | sub session_expire_key { |
369 | my ( $c, %keys ) = @_; |
370 | |
371 | my $now = time; |
4207ce8d |
372 | @{ $c->session->{__expire_keys} }{ keys %keys } = |
373 | map { $now + $_ } values %keys; |
b7acf64e |
374 | } |
375 | |
9e447f9d |
376 | sub initialize_session_data { |
9a9252c2 |
377 | my $c = shift; |
9e447f9d |
378 | |
9a9252c2 |
379 | my $now = time; |
9e447f9d |
380 | |
4207ce8d |
381 | return $c->_session( |
382 | { |
383 | __created => $now, |
384 | __updated => $now, |
385 | |
386 | ( |
387 | $c->config->{session}{verify_address} |
388 | ? ( __address => $c->request->address ) |
389 | : () |
390 | ), |
391 | } |
392 | ); |
9e447f9d |
393 | } |
394 | |
9e447f9d |
395 | sub generate_session_id { |
396 | my $c = shift; |
397 | |
398 | my $digest = $c->_find_digest(); |
399 | $digest->add( $c->session_hash_seed() ); |
400 | return $digest->hexdigest; |
401 | } |
402 | |
1dbf4cd5 |
403 | sub create_session_id_if_needed { |
78476ce0 |
404 | my $c = shift; |
1dbf4cd5 |
405 | $c->create_session_id unless $c->sessionid; |
406 | } |
78476ce0 |
407 | |
1dbf4cd5 |
408 | sub create_session_id { |
409 | my $c = shift; |
410 | |
e5b2372a |
411 | my $sid = $c->generate_session_id; |
78476ce0 |
412 | |
e5b2372a |
413 | $c->log->debug(qq/Created session "$sid"/) if $c->debug; |
78476ce0 |
414 | |
e5b2372a |
415 | $c->_sessionid($sid); |
416 | $c->reset_session_expires; |
417 | $c->set_session_id($sid); |
418 | |
419 | return $sid; |
78476ce0 |
420 | } |
421 | |
9e447f9d |
422 | my $counter; |
9a9252c2 |
423 | |
9e447f9d |
424 | sub session_hash_seed { |
9a9252c2 |
425 | my $c = shift; |
426 | |
427 | return join( "", ++$counter, time, rand, $$, {}, overload::StrVal($c), ); |
9e447f9d |
428 | } |
429 | |
430 | my $usable; |
9a9252c2 |
431 | |
9e447f9d |
432 | sub _find_digest () { |
9a9252c2 |
433 | unless ($usable) { |
d44bc687 |
434 | foreach my $alg (qw/SHA-1 SHA-256 MD5/) { |
4207ce8d |
435 | if ( eval { Digest->new($alg) } ) { |
5faaa4b0 |
436 | $usable = $alg; |
437 | last; |
438 | } |
7d139eeb |
439 | } |
4207ce8d |
440 | Catalyst::Exception->throw( |
9a9252c2 |
441 | "Could not find a suitable Digest module. Please install " |
4207ce8d |
442 | . "Digest::SHA1, Digest::SHA, or Digest::MD5" ) |
443 | unless $usable; |
9a9252c2 |
444 | } |
9e447f9d |
445 | |
446 | return Digest->new($usable); |
447 | } |
448 | |
99b2191e |
449 | sub dump_these { |
450 | my $c = shift; |
451 | |
452 | ( |
453 | $c->NEXT::dump_these(), |
454 | |
455 | $c->sessionid |
456 | ? ( [ "Session ID" => $c->sessionid ], [ Session => $c->session ], ) |
457 | : () |
458 | ); |
459 | } |
460 | |
e5b2372a |
461 | |
462 | sub get_session_id { shift->NEXT::get_session_id(@_) } |
463 | sub set_session_id { shift->NEXT::set_session_id(@_) } |
464 | sub delete_session_id { shift->NEXT::delete_session_id(@_) } |
4c79feb6 |
465 | sub extend_session_id { shift->NEXT::extend_session_id(@_) } |
e5b2372a |
466 | |
9e447f9d |
467 | __PACKAGE__; |
468 | |
469 | __END__ |
470 | |
471 | =pod |
472 | |
473 | =head1 NAME |
474 | |
475 | Catalyst::Plugin::Session - Generic Session plugin - ties together server side |
fb1a4ac3 |
476 | storage and client side state required to maintain session data. |
9e447f9d |
477 | |
478 | =head1 SYNOPSIS |
479 | |
8f0b4c16 |
480 | # To get sessions to "just work", all you need to do is use these plugins: |
481 | |
482 | use Catalyst qw/ |
483 | Session |
484 | Session::Store::FastMmap |
485 | Session::State::Cookie |
486 | /; |
487 | |
488 | # you can replace Store::FastMmap with Store::File - both have sensible |
489 | # default configurations (see their docs for details) |
490 | |
491 | # more complicated backends are available for other scenarios (DBI storage, |
492 | # etc) |
493 | |
494 | |
495 | # after you've loaded the plugins you can save session data |
496 | # For example, if you are writing a shopping cart, it could be implemented |
497 | # like this: |
9e447f9d |
498 | |
229a5b53 |
499 | sub add_item : Local { |
500 | my ( $self, $c ) = @_; |
501 | |
502 | my $item_id = $c->req->param("item"); |
503 | |
8f0b4c16 |
504 | # $c->session is a hash ref, a bit like $c->stash |
505 | # the difference is that it' preserved across requests |
229a5b53 |
506 | |
507 | push @{ $c->session->{items} }, $item_id; |
508 | |
509 | $c->forward("MyView"); |
510 | } |
511 | |
512 | sub display_items : Local { |
513 | my ( $self, $c ) = @_; |
514 | |
515 | # values in $c->session are restored |
516 | $c->stash->{items_to_display} = |
8f0b4c16 |
517 | [ map { MyModel->retrieve($_) } @{ $c->session->{items} } ]; |
229a5b53 |
518 | |
519 | $c->forward("MyView"); |
520 | } |
521 | |
9e447f9d |
522 | =head1 DESCRIPTION |
523 | |
524 | The Session plugin is the base of two related parts of functionality required |
525 | for session management in web applications. |
526 | |
527 | The first part, the State, is getting the browser to repeat back a session key, |
528 | so that the web application can identify the client and logically string |
529 | several requests together into a session. |
530 | |
531 | The second part, the Store, deals with the actual storage of information about |
532 | the client. This data is stored so that the it may be revived for every request |
533 | made by the same client. |
534 | |
535 | This plugin links the two pieces together. |
536 | |
8f0b4c16 |
537 | =head1 RECCOMENDED BACKENDS |
538 | |
539 | =over 4 |
540 | |
541 | =item Session::State::Cookie |
542 | |
543 | The only really sane way to do state is using cookies. |
544 | |
545 | =item Session::Store::File |
546 | |
547 | A portable backend, based on Cache::File. |
548 | |
549 | =item Session::Store::FastMmap |
550 | |
551 | A fast and flexible backend, based on Cache::FastMmap. |
552 | |
553 | =back |
554 | |
9e447f9d |
555 | =head1 METHODS |
556 | |
557 | =over 4 |
558 | |
559 | =item sessionid |
560 | |
561 | An accessor for the session ID value. |
562 | |
563 | =item session |
564 | |
565 | Returns a hash reference that might contain unserialized values from previous |
566 | requests in the same session, and whose modified value will be saved for future |
567 | requests. |
568 | |
569 | This method will automatically create a new session and session ID if none |
570 | exists. |
571 | |
ab634fee |
572 | =item session_expires |
573 | |
574 | =item session_expires $reset |
575 | |
576 | This method returns the time when the current session will expire, or 0 if |
577 | there is no current session. If there is a session and it already expired, it |
578 | will delete the session and return 0 as well. |
579 | |
580 | If the C<$reset> parameter is true, and there is a session ID the expiry time |
581 | will be reset to the current time plus the time to live (see |
582 | L</CONFIGURATION>). This is used when creating a new session. |
583 | |
07e714d2 |
584 | =item flash |
585 | |
586 | This is like Ruby on Rails' flash data structure. Think of it as a stash that |
44ab6d1c |
587 | lasts for longer than one request, letting you redirect instead of forward. |
588 | |
589 | The flash data will be cleaned up only on requests on which actually use |
590 | $c->flash (thus allowing multiple redirections), and the policy is to delete |
bf6bd311 |
591 | all the keys which haven't changed since the flash data was loaded at the end |
592 | of every request. |
07e714d2 |
593 | |
594 | sub moose : Local { |
595 | my ( $self, $c ) = @_; |
596 | |
597 | $c->flash->{beans} = 10; |
598 | $c->response->redirect( $c->uri_for("foo") ); |
599 | } |
600 | |
601 | sub foo : Local { |
602 | my ( $self, $c ) = @_; |
603 | |
604 | my $value = $c->flash->{beans}; |
605 | |
606 | # ... |
607 | |
608 | $c->response->redirect( $c->uri_for("bar") ); |
609 | } |
610 | |
611 | sub bar : Local { |
612 | my ( $self, $c ) = @_; |
613 | |
614 | if ( exists $c->flash->{beans} ) { # false |
615 | |
616 | } |
617 | } |
618 | |
bf6bd311 |
619 | =item keep_flash @keys |
620 | |
621 | If you wawnt to keep a flash key for the next request too, even if it hasn't |
622 | changed, call C<keep_flash> and pass in the keys as arguments. |
623 | |
fffeb18f |
624 | =item delete_session REASON |
625 | |
626 | This method is used to invalidate a session. It takes an optional parameter |
627 | which will be saved in C<session_delete_reason> if provided. |
628 | |
9e447f9d |
629 | =item session_delete_reason |
630 | |
631 | This accessor contains a string with the reason a session was deleted. Possible |
632 | values include: |
633 | |
634 | =over 4 |
635 | |
636 | =item * |
637 | |
638 | C<address mismatch> |
639 | |
640 | =item * |
641 | |
642 | C<session expired> |
643 | |
644 | =back |
645 | |
b7acf64e |
646 | =item session_expire_key $key, $ttl |
647 | |
648 | Mark a key to expire at a certain time (only useful when shorter than the |
649 | expiry time for the whole session). |
650 | |
651 | For example: |
652 | |
653 | __PACKAGE__->config->{session}{expires} = 1000000000000; # forever |
654 | |
655 | # later |
656 | |
657 | $c->session_expire_key( __user => 3600 ); |
658 | |
659 | Will make the session data survive, but the user will still be logged out after |
660 | an hour. |
661 | |
662 | Note that these values are not auto extended. |
663 | |
8f0b4c16 |
664 | =back |
665 | |
10c72079 |
666 | =head1 INTERNAL METHODS |
8f0b4c16 |
667 | |
668 | =over 4 |
669 | |
9e447f9d |
670 | =item setup |
671 | |
672 | This method is extended to also make calls to |
673 | C<check_session_plugin_requirements> and C<setup_session>. |
674 | |
675 | =item check_session_plugin_requirements |
676 | |
677 | This method ensures that a State and a Store plugin are also in use by the |
678 | application. |
679 | |
680 | =item setup_session |
681 | |
682 | This method populates C<< $c->config->{session} >> with the default values |
683 | listed in L</CONFIGURATION>. |
684 | |
685 | =item prepare_action |
686 | |
68fd02ae |
687 | This methoid is extended. |
688 | |
689 | It's only effect is if the (off by default) C<flash_to_stash> configuration |
690 | parameter is on - then it will copy the contents of the flash to the stash at |
691 | prepare time. |
9e447f9d |
692 | |
693 | =item finalize |
694 | |
695 | This method is extended and will extend the expiry time, as well as persist the |
696 | session data if a session exists. |
697 | |
9e447f9d |
698 | =item initialize_session_data |
699 | |
700 | This method will initialize the internal structure of the session, and is |
701 | called by the C<session> method if appropriate. |
702 | |
68fd02ae |
703 | =item create_session_id |
704 | |
705 | Creates a new session id using C<generate_session_id> if there is no session ID |
706 | yet. |
707 | |
ab634fee |
708 | =item validate_session_id SID |
709 | |
710 | Make sure a session ID is of the right format. |
711 | |
712 | This currently ensures that the session ID string is any amount of case |
713 | insensitive hexadecimal characters. |
714 | |
229a5b53 |
715 | =item generate_session_id |
716 | |
717 | This method will return a string that can be used as a session ID. It is |
718 | supposed to be a reasonably random string with enough bits to prevent |
719 | collision. It basically takes C<session_hash_seed> and hashes it using SHA-1, |
720 | MD5 or SHA-256, depending on the availibility of these modules. |
721 | |
722 | =item session_hash_seed |
723 | |
724 | This method is actually rather internal to generate_session_id, but should be |
725 | overridable in case you want to provide more random data. |
726 | |
727 | Currently it returns a concatenated string which contains: |
728 | |
729 | =over 4 |
730 | |
731 | =item * |
732 | |
733 | A counter |
734 | |
735 | =item * |
736 | |
737 | The current time |
738 | |
739 | =item * |
740 | |
741 | One value from C<rand>. |
742 | |
743 | =item * |
744 | |
745 | The stringified value of a newly allocated hash reference |
746 | |
747 | =item * |
748 | |
749 | The stringified value of the Catalyst context object |
750 | |
751 | =back |
752 | |
753 | In the hopes that those combined values are entropic enough for most uses. If |
754 | this is not the case you can replace C<session_hash_seed> with e.g. |
755 | |
756 | sub session_hash_seed { |
757 | open my $fh, "<", "/dev/random"; |
758 | read $fh, my $bytes, 20; |
759 | close $fh; |
760 | return $bytes; |
761 | } |
762 | |
763 | Or even more directly, replace C<generate_session_id>: |
764 | |
765 | sub generate_session_id { |
766 | open my $fh, "<", "/dev/random"; |
767 | read $fh, my $bytes, 20; |
768 | close $fh; |
769 | return unpack("H*", $bytes); |
770 | } |
771 | |
772 | Also have a look at L<Crypt::Random> and the various openssl bindings - these |
773 | modules provide APIs for cryptographically secure random data. |
774 | |
99b2191e |
775 | =item dump_these |
776 | |
777 | See L<Catalyst/dump_these> - ammends the session data structure to the list of |
778 | dumped objects if session ID is defined. |
779 | |
9e447f9d |
780 | =back |
781 | |
a92c8aeb |
782 | =head1 USING SESSIONS DURING PREPARE |
783 | |
784 | The earliest point in time at which you may use the session data is after |
785 | L<Catalyst::Plugin::Session>'s C<prepare_action> has finished. |
786 | |
787 | State plugins must set $c->session ID before C<prepare_action>, and during |
788 | C<prepare_action> L<Catalyst::Plugin::Session> will actually load the data from |
789 | the store. |
790 | |
791 | sub prepare_action { |
792 | my $c = shift; |
793 | |
794 | # don't touch $c->session yet! |
b1cd7d77 |
795 | |
a92c8aeb |
796 | $c->NEXT::prepare_action( @_ ); |
797 | |
798 | $c->session; # this is OK |
799 | $c->sessionid; # this is also OK |
800 | } |
801 | |
9e447f9d |
802 | =head1 CONFIGURATION |
803 | |
229a5b53 |
804 | $c->config->{session} = { |
805 | expires => 1234, |
806 | }; |
9e447f9d |
807 | |
808 | All configuation parameters are provided in a hash reference under the |
809 | C<session> key in the configuration hash. |
810 | |
811 | =over 4 |
812 | |
813 | =item expires |
814 | |
815 | The time-to-live of each session, expressed in seconds. Defaults to 7200 (two |
816 | hours). |
817 | |
818 | =item verify_address |
819 | |
8c7e922c |
820 | When true, C<<$c->request->address>> will be checked at prepare time. If it is |
821 | not the same as the address that initiated the session, the session is deleted. |
9e447f9d |
822 | |
68fd02ae |
823 | =item flash_to_stash |
824 | |
825 | This option makes it easier to have actions behave the same whether they were |
826 | forwarded to or redirected to. On prepare time it copies the contents of |
827 | C<flash> (if any) to the stash. |
828 | |
9e447f9d |
829 | =back |
830 | |
831 | =head1 SPECIAL KEYS |
832 | |
833 | The hash reference returned by C<< $c->session >> contains several keys which |
834 | are automatically set: |
835 | |
836 | =over 4 |
837 | |
838 | =item __expires |
839 | |
ab634fee |
840 | This key no longer exists. Use C<session_expires> instead. |
9e447f9d |
841 | |
842 | =item __updated |
843 | |
d44bc687 |
844 | The last time a session was saved to the store. |
9e447f9d |
845 | |
846 | =item __created |
847 | |
848 | The time when the session was first created. |
849 | |
850 | =item __address |
851 | |
852 | The value of C<< $c->request->address >> at the time the session was created. |
8c7e922c |
853 | This value is only populated if C<verify_address> is true in the configuration. |
9e447f9d |
854 | |
855 | =back |
856 | |
c80e9f04 |
857 | =head1 CAVEATS |
858 | |
a552e4b5 |
859 | =head2 Round the Robin Proxies |
860 | |
c80e9f04 |
861 | C<verify_address> could make your site inaccessible to users who are behind |
862 | load balanced proxies. Some ISPs may give a different IP to each request by the |
863 | same client due to this type of proxying. If addresses are verified these |
864 | users' sessions cannot persist. |
865 | |
866 | To let these users access your site you can either disable address verification |
867 | as a whole, or provide a checkbox in the login dialog that tells the server |
868 | that it's OK for the address of the client to change. When the server sees that |
869 | this box is checked it should delete the C<__address> sepcial key from the |
870 | session hash when the hash is first created. |
871 | |
a552e4b5 |
872 | =head2 Race Conditions |
873 | |
874 | In this day and age where cleaning detergents and dutch football (not the |
875 | american kind) teams roam the plains in great numbers, requests may happen |
876 | simultaneously. This means that there is some risk of session data being |
877 | overwritten, like this: |
878 | |
879 | =over 4 |
880 | |
881 | =item 1. |
882 | |
883 | request a starts, request b starts, with the same session id |
884 | |
885 | =item 2. |
886 | |
887 | session data is loaded in request a |
888 | |
889 | =item 3. |
890 | |
891 | session data is loaded in request b |
892 | |
893 | =item 4. |
894 | |
895 | session data is changed in request a |
896 | |
897 | =item 5. |
898 | |
899 | request a finishes, session data is updated and written to store |
900 | |
901 | =item 6. |
902 | |
903 | request b finishes, session data is updated and written to store, overwriting |
904 | changes by request a |
905 | |
906 | =back |
907 | |
908 | If this is a concern in your application, a soon to be developed locking |
909 | solution is the only safe way to go. This will have a bigger overhead. |
910 | |
911 | For applications where any given user is only making one request at a time this |
912 | plugin should be safe enough. |
913 | |
d45028d6 |
914 | =head1 AUTHORS |
915 | |
baa9db9c |
916 | =over 4 |
917 | |
918 | =item Andy Grundman |
919 | |
920 | =item Christian Hansen |
921 | |
922 | =item Yuval Kogman, C<nothingmuch@woobling.org> (current maintainer) |
923 | |
924 | =item Sebastian Riedel |
925 | |
926 | =back |
927 | |
928 | And countless other contributers from #catalyst. Thanks guys! |
d45028d6 |
929 | |
cc40ae4b |
930 | =head1 COPYRIGHT & LICENSE |
d45028d6 |
931 | |
932 | Copyright (c) 2005 the aforementioned authors. All rights |
933 | reserved. This program is free software; you can redistribute |
934 | it and/or modify it under the same terms as Perl itself. |
935 | |
9e447f9d |
936 | =cut |
937 | |
938 | |