forked from 1EdTech/LTI-Tool-Provider-Library-PHP
-
Notifications
You must be signed in to change notification settings - Fork 6
/
ToolProvider.php
1289 lines (1189 loc) · 49.5 KB
/
ToolProvider.php
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
<?php
namespace IMSGlobal\LTI\ToolProvider;
use IMSGlobal\LTI\Profile\Item;
use IMSGlobal\LTI\ToolProvider\DataConnector\DataConnector;
use IMSGlobal\LTI\ToolProvider\MediaType;
use IMSGlobal\LTI\Profile;
use IMSGlobal\LTI\HTTPMessage;
use IMSGlobal\LTI\OAuth;
/**
* Class to represent an LTI Tool Provider
*
* @author Stephen P Vickers <svickers@imsglobal.org>
* @copyright IMS Global Learning Consortium Inc
* @date 2016
* @version 3.0.2
* @license GNU Lesser General Public License, version 3 (<http://www.gnu.org/licenses/lgpl.html>)
*/
class ToolProvider
{
/**
* Default connection error message.
*/
const CONNECTION_ERROR_MESSAGE = 'Sorry, there was an error connecting you to the application.';
/**
* LTI version 1 for messages.
*/
const LTI_VERSION1 = 'LTI-1p0';
/**
* LTI version 2 for messages.
*/
const LTI_VERSION2 = 'LTI-2p0';
/**
* Use ID value only.
*/
const ID_SCOPE_ID_ONLY = 0;
/**
* Prefix an ID with the consumer key.
*/
const ID_SCOPE_GLOBAL = 1;
/**
* Prefix the ID with the consumer key and context ID.
*/
const ID_SCOPE_CONTEXT = 2;
/**
* Prefix the ID with the consumer key and resource ID.
*/
const ID_SCOPE_RESOURCE = 3;
/**
* Character used to separate each element of an ID.
*/
const ID_SCOPE_SEPARATOR = ':';
/**
* Permitted LTI versions for messages.
*/
private static $LTI_VERSIONS = array(self::LTI_VERSION1, self::LTI_VERSION2);
/**
* List of supported message types and associated class methods.
*/
private static $MESSAGE_TYPES = array('basic-lti-launch-request' => 'onLaunch',
'ContentItemSelectionRequest' => 'onContentItem',
'ToolProxyRegistrationRequest' => 'register');
/**
* List of supported message types and associated class methods
*
* @var array $METHOD_NAMES
*/
private static $METHOD_NAMES = array('basic-lti-launch-request' => 'onLaunch',
'ContentItemSelectionRequest' => 'onContentItem',
'ToolProxyRegistrationRequest' => 'onRegister');
/**
* Names of LTI parameters to be retained in the consumer settings property.
*
* @var array $LTI_CONSUMER_SETTING_NAMES
*/
private static $LTI_CONSUMER_SETTING_NAMES = array('custom_tc_profile_url', 'custom_system_setting_url');
/**
* Names of LTI parameters to be retained in the context settings property.
*
* @var array $LTI_CONTEXT_SETTING_NAMES
*/
private static $LTI_CONTEXT_SETTING_NAMES = array('custom_context_setting_url',
'custom_lineitems_url', 'custom_results_url',
'custom_context_memberships_url');
/**
* Names of LTI parameters to be retained in the resource link settings property.
*
* @var array $LTI_RESOURCE_LINK_SETTING_NAMES
*/
private static $LTI_RESOURCE_LINK_SETTING_NAMES = array('lis_result_sourcedid', 'lis_outcome_service_url',
'ext_ims_lis_basic_outcome_url', 'ext_ims_lis_resultvalue_sourcedids',
'ext_ims_lis_memberships_id', 'ext_ims_lis_memberships_url',
'ext_ims_lti_tool_setting', 'ext_ims_lti_tool_setting_id', 'ext_ims_lti_tool_setting_url',
'custom_link_setting_url',
'custom_lineitem_url', 'custom_result_url');
/**
* Names of LTI custom parameter substitution variables (or capabilities) and their associated default message parameter names.
*
* @var array $CUSTOM_SUBSTITUTION_VARIABLES
*/
private static $CUSTOM_SUBSTITUTION_VARIABLES = array('User.id' => 'user_id',
'User.image' => 'user_image',
'User.username' => 'username',
'User.scope.mentor' => 'role_scope_mentor',
'Membership.role' => 'roles',
'Person.sourcedId' => 'lis_person_sourcedid',
'Person.name.full' => 'lis_person_name_full',
'Person.name.family' => 'lis_person_name_family',
'Person.name.given' => 'lis_person_name_given',
'Person.email.primary' => 'lis_person_contact_email_primary',
'Context.id' => 'context_id',
'Context.type' => 'context_type',
'Context.title' => 'context_title',
'Context.label' => 'context_label',
'CourseOffering.sourcedId' => 'lis_course_offering_sourcedid',
'CourseSection.sourcedId' => 'lis_course_section_sourcedid',
'CourseSection.label' => 'context_label',
'CourseSection.title' => 'context_title',
'ResourceLink.id' => 'resource_link_id',
'ResourceLink.title' => 'resource_link_title',
'ResourceLink.description' => 'resource_link_description',
'Result.sourcedId' => 'lis_result_sourcedid',
'BasicOutcome.url' => 'lis_outcome_service_url',
'ToolConsumerProfile.url' => 'custom_tc_profile_url',
'ToolProxy.url' => 'tool_proxy_url',
'ToolProxy.custom.url' => 'custom_system_setting_url',
'ToolProxyBinding.custom.url' => 'custom_context_setting_url',
'LtiLink.custom.url' => 'custom_link_setting_url',
'LineItems.url' => 'custom_lineitems_url',
'LineItem.url' => 'custom_lineitem_url',
'Results.url' => 'custom_results_url',
'Result.url' => 'custom_result_url',
'ToolProxyBinding.memberships.url' => 'custom_context_memberships_url');
/**
* True if the last request was successful.
*
* @var boolean $ok
*/
public $ok = true;
/**
* Tool Consumer object.
*
* @var ToolConsumer $consumer
*/
public $consumer = null;
/**
* Return URL provided by tool consumer.
*
* @var string $returnUrl
*/
public $returnUrl = null;
/**
* User object.
*
* @var User $user
*/
public $user = null;
/**
* Resource link object.
*
* @var ResourceLink $resourceLink
*/
public $resourceLink = null;
/**
* Context object.
*
* @var Context $context
*/
public $context = null;
/**
* Data connector object.
*
* @var DataConnector $dataConnector
*/
public $dataConnector = null;
/**
* Default email domain.
*
* @var string $defaultEmail
*/
public $defaultEmail = '';
/**
* Scope to use for user IDs.
*
* @var int $idScope
*/
public $idScope = self::ID_SCOPE_ID_ONLY;
/**
* Whether shared resource link arrangements are permitted.
*
* @var boolean $allowSharing
*/
public $allowSharing = false;
/**
* Message for last request processed
*
* @var string $message
*/
public $message = self::CONNECTION_ERROR_MESSAGE;
/**
* Error message for last request processed.
*
* @var string $reason
*/
public $reason = null;
/**
* Details for error message relating to last request processed.
*
* @var array $details
*/
public $details = array();
/**
* Base URL for tool provider service
*
* @var string $baseUrl
*/
public $baseUrl = null;
/**
* Vendor details
*
* @var Item $vendor
*/
public $vendor = null;
/**
* Product details
*
* @var Item $product
*/
public $product = null;
/**
* Services required by Tool Provider
*
* @var array $requiredServices
*/
public $requiredServices = null;
/**
* Optional services used by Tool Provider
*
* @var array $optionalServices
*/
public $optionalServices = null;
/**
* Resource handlers for Tool Provider
*
* @var array $resourceHandlers
*/
public $resourceHandlers = null;
/**
* URL to redirect user to on successful completion of the request.
*
* @var string $redirectUrl
*/
protected $redirectUrl = null;
/**
* URL to redirect user to on successful completion of the request.
*
* @var string $mediaTypes
*/
protected $mediaTypes = null;
/**
* URL to redirect user to on successful completion of the request.
*
* @var string $documentTargets
*/
protected $documentTargets = null;
/**
* HTML to be displayed on a successful completion of the request.
*
* @var string $output
*/
protected $output = null;
/**
* HTML to be displayed on an unsuccessful completion of the request and no return URL is available.
*
* @var string $errorOutput
*/
protected $errorOutput = null;
/**
* Whether debug messages explaining the cause of errors are to be returned to the tool consumer.
*
* @var boolean $debugMode
*/
protected $debugMode = false;
/**
* Callback functions for handling requests.
*
* @var array $callbackHandler
*/
private $callbackHandler = null;
/**
* LTI parameter constraints for auto validation checks.
*
* @var array $constraints
*/
private $constraints = null;
/**
* Class constructor
*
* @param DataConnector $dataConnector Object containing a database connection object
*/
function __construct($dataConnector)
{
$this->constraints = array();
$this->dataConnector = $dataConnector;
$this->ok = !is_null($this->dataConnector);
// Set debug mode
$this->debugMode = isset($_POST['custom_debug']) && (strtolower($_POST['custom_debug']) === 'true');
// Set return URL if available
if (isset($_POST['launch_presentation_return_url'])) {
$this->returnUrl = $_POST['launch_presentation_return_url'];
} else if (isset($_POST['content_item_return_url'])) {
$this->returnUrl = $_POST['content_item_return_url'];
}
$this->vendor = new Profile\Item();
$this->product = new Profile\Item();
$this->requiredServices = array();
$this->optionalServices = array();
$this->resourceHandlers = array();
}
/**
* Process an incoming request
*/
public function handleRequest()
{
if ($this->ok) {
if ($this->authenticate()) {
$this->doCallback();
}
}
$this->result();
}
/**
* Add a parameter constraint to be checked on launch
*
* @param string $name Name of parameter to be checked
* @param boolean $required True if parameter is required (optional, default is true)
* @param int $maxLength Maximum permitted length of parameter value (optional, default is null)
* @param array $messageTypes Array of message types to which the constraint applies (optional, default is all)
*/
public function setParameterConstraint($name, $required = true, $maxLength = null, $messageTypes = null)
{
$name = trim($name);
if (strlen($name) > 0) {
$this->constraints[$name] = array('required' => $required, 'max_length' => $maxLength, 'messages' => $messageTypes);
}
}
/**
* Get an array of defined tool consumers
*
* @return array Array of ToolConsumer objects
*/
public function getConsumers()
{
return $this->dataConnector->getToolConsumers();
}
/**
* Find an offered service based on a media type and HTTP action(s)
*
* @param string $format Media type required
* @param array $methods Array of HTTP actions required
*
* @return object The service object
*/
public function findService($format, $methods)
{
$found = false;
$services = $this->consumer->profile->service_offered;
if (is_array($services)) {
$n = -1;
foreach ($services as $service) {
$n++;
if (!is_array($service->format) || !in_array($format, $service->format)) {
continue;
}
$missing = array();
foreach ($methods as $method) {
if (!is_array($service->action) || !in_array($method, $service->action)) {
$missing[] = $method;
}
}
$methods = $missing;
if (count($methods) <= 0) {
$found = $service;
break;
}
}
}
return $found;
}
/**
* Send the tool proxy to the Tool Consumer
*
* @return boolean True if the tool proxy was accepted
*/
public function doToolProxyService()
{
// Create tool proxy
$toolProxyService = $this->findService('application/vnd.ims.lti.v2.toolproxy+json', array('POST'));
$secret = DataConnector::getRandomString(12);
$toolProxy = new MediaType\ToolProxy($this, $toolProxyService, $secret);
$http = $this->consumer->doServiceRequest($toolProxyService, 'POST', 'application/vnd.ims.lti.v2.toolproxy+json', json_encode($toolProxy));
$ok = $http->ok && ($http->status == 201) && isset($http->responseJson->tool_proxy_guid) && (strlen($http->responseJson->tool_proxy_guid) > 0);
if ($ok) {
$this->consumer->setKey($http->responseJson->tool_proxy_guid);
$this->consumer->secret = $toolProxy->security_contract->shared_secret;
$this->consumer->toolProxy = json_encode($toolProxy);
$this->consumer->save();
}
return $ok;
}
/**
* Get an array of fully qualified user roles
*
* @param mixed $roles Comma-separated list of roles or array of roles
*
* @return array Array of roles
*/
public static function parseRoles($roles)
{
if (!is_array($roles)) {
$roles = explode(',', $roles);
}
$parsedRoles = array();
foreach ($roles as $role) {
$role = trim($role);
if (!empty($role)) {
if (strpos( $role, '://purl.imsglobal.org/vocab/lis/v2/' ) !== false) {
// Get trailing #anchor
$fragment = parse_url($role, PHP_URL_FRAGMENT);
if (!empty( $fragment )) {
$role = $fragment;
}
}
if (substr($role, 0, 4) !== 'urn:') {
$role = 'urn:lti:role:ims/lis/' . $role;
}
$parsedRoles[] = $role;
}
}
return $parsedRoles;
}
/**
* Generate a web page containing an auto-submitted form of parameters.
*
* @param string $url URL to which the form should be submitted
* @param array $params Array of form parameters
* @param string $target Name of target (optional)
* @return string
*/
public static function sendForm($url, $params, $target = '')
{
$page = <<< EOD
<html>
<head>
<title>IMS LTI message</title>
<script type="text/javascript">
//<![CDATA[
function doOnLoad() {
document.forms[0].submit();
}
window.onload=doOnLoad;
//]]>
</script>
</head>
<body>
<form action="{$url}" method="post" target="" encType="application/x-www-form-urlencoded">
EOD;
foreach($params as $key => $value ) {
$key = htmlentities($key, ENT_COMPAT | ENT_HTML401, 'UTF-8');
$value = htmlentities($value, ENT_COMPAT | ENT_HTML401, 'UTF-8');
$page .= <<< EOD
<input type="hidden" name="{$key}" value="{$value}" />
EOD;
}
$page .= <<< EOD
</form>
</body>
</html>
EOD;
return $page;
}
###
### PROTECTED METHODS
###
/**
* Process a valid launch request
*
* @return boolean True if no error
*/
protected function onLaunch()
{
$this->onError();
}
/**
* Process a valid content-item request
*
* @return boolean True if no error
*/
protected function onContentItem()
{
$this->onError();
}
/**
* Process a valid tool proxy registration request
*
* @return boolean True if no error
*/
protected function onRegister() {
$this->onError();
}
/**
* Process a response to an invalid request
*
* @return boolean True if no further error processing required
*/
protected function onError()
{
$this->doCallback('onError');
}
###
### PRIVATE METHODS
###
/**
* Call any callback function for the requested action.
*
* This function may set the redirect_url and output properties.
*
* @param string|null $method
*
* @return void True if no error reported
*/
private function doCallback($method = null)
{
$callback = $method;
if (is_null($callback)) {
$callback = self::$METHOD_NAMES[$_POST['lti_message_type']];
}
if (method_exists($this, $callback)) {
$result = $this->$callback();
} else if (is_null($method) && $this->ok) {
$this->ok = false;
$this->reason = "Message type not supported: {$_POST['lti_message_type']}";
}
if ($this->ok && ($_POST['lti_message_type'] == 'ToolProxyRegistrationRequest')) {
$this->consumer->save();
}
}
/**
* Perform the result of an action.
*
* This function may redirect the user to another URL rather than returning a value.
*
* @return string Output to be displayed (redirection, or display HTML or message)
*/
private function result()
{
$ok = false;
if (!$this->ok) {
$ok = $this->onError();
}
if (!$ok) {
if (!$this->ok) {
// If not valid, return an error message to the tool consumer if a return URL is provided
if (!empty($this->returnUrl)) {
$errorUrl = $this->returnUrl;
if (strpos($errorUrl, '?') === false) {
$errorUrl .= '?';
} else {
$errorUrl .= '&';
}
if ($this->debugMode && !is_null($this->reason)) {
$errorUrl .= 'lti_errormsg=' . urlencode("Debug error: $this->reason");
} else {
$errorUrl .= 'lti_errormsg=' . urlencode($this->message);
if (!is_null($this->reason)) {
$errorUrl .= '<i_errorlog=' . urlencode("Debug error: $this->reason");
}
}
if (!is_null($this->consumer) && isset($_POST['lti_message_type']) && ($_POST['lti_message_type'] === 'ContentItemSelectionRequest')) {
$formParams = array();
if (isset($_POST['data'])) {
$formParams['data'] = $_POST['data'];
}
$version = (isset($_POST['lti_version'])) ? $_POST['lti_version'] : self::LTI_VERSION1;
$formParams = $this->consumer->signParameters($errorUrl, 'ContentItemSelection', $version, $formParams);
$page = self::sendForm($errorUrl, $formParams);
echo $page;
} else {
header("Location: {$errorUrl}");
}
exit;
} else {
if (!is_null($this->errorOutput)) {
echo $this->errorOutput;
} else if ($this->debugMode && !empty($this->reason)) {
echo "Debug error: {$this->reason}";
} else {
echo "Error: {$this->message}";
}
}
} else if (!is_null($this->redirectUrl)) {
header("Location: {$this->redirectUrl}");
exit;
} else if (!is_null($this->output)) {
echo $this->output;
}
}
}
/**
* Check the authenticity of the LTI launch request.
*
* The consumer, resource link and user objects will be initialised if the request is valid.
*
* @return boolean True if the request has been successfully validated.
*/
private function authenticate()
{
// Get the consumer
$doSaveConsumer = false;
// Check all required launch parameters
$this->ok = isset($_POST['lti_message_type']) && array_key_exists($_POST['lti_message_type'], self::$MESSAGE_TYPES);
if (!$this->ok) {
$this->reason = 'Invalid or missing lti_message_type parameter.';
}
if ($this->ok) {
$this->ok = isset($_POST['lti_version']) && in_array($_POST['lti_version'], self::$LTI_VERSIONS);
if (!$this->ok) {
$this->reason = 'Invalid or missing lti_version parameter.';
}
}
if ($this->ok) {
if ($_POST['lti_message_type'] === 'basic-lti-launch-request') {
$this->ok = isset($_POST['resource_link_id']) && (strlen(trim($_POST['resource_link_id'])) > 0);
if (!$this->ok) {
$this->reason = 'Missing resource link ID.';
}
} else if ($_POST['lti_message_type'] === 'ContentItemSelectionRequest') {
if (isset($_POST['accept_media_types']) && (strlen(trim($_POST['accept_media_types'])) > 0)) {
$mediaTypes = array_filter(explode(',', str_replace(' ', '', $_POST['accept_media_types'])), 'strlen');
$mediaTypes = array_unique($mediaTypes);
$this->ok = count($mediaTypes) > 0;
if (!$this->ok) {
$this->reason = 'No accept_media_types found.';
} else {
$this->mediaTypes = $mediaTypes;
}
} else {
$this->ok = false;
}
if ($this->ok && isset($_POST['accept_presentation_document_targets']) && (strlen(trim($_POST['accept_presentation_document_targets'])) > 0)) {
$documentTargets = array_filter(explode(',', str_replace(' ', '', $_POST['accept_presentation_document_targets'])), 'strlen');
$documentTargets = array_unique($documentTargets);
$this->ok = count($documentTargets) > 0;
if (!$this->ok) {
$this->reason = 'Missing or empty accept_presentation_document_targets parameter.';
} else {
foreach ($documentTargets as $documentTarget) {
$this->ok = $this->checkValue($documentTarget, array('embed', 'frame', 'iframe', 'window', 'popup', 'overlay', 'none'),
'Invalid value in accept_presentation_document_targets parameter: %s.');
if (!$this->ok) {
break;
}
}
if ($this->ok) {
$this->documentTargets = $documentTargets;
}
}
} else {
$this->ok = false;
}
if ($this->ok) {
$this->ok = isset($_POST['content_item_return_url']) && (strlen(trim($_POST['content_item_return_url'])) > 0);
if (!$this->ok) {
$this->reason = 'Missing content_item_return_url parameter.';
}
}
} else if ($_POST['lti_message_type'] == 'ToolProxyRegistrationRequest') {
$this->ok = ((isset($_POST['reg_key']) && (strlen(trim($_POST['reg_key'])) > 0)) &&
(isset($_POST['reg_password']) && (strlen(trim($_POST['reg_password'])) > 0)) &&
(isset($_POST['tc_profile_url']) && (strlen(trim($_POST['tc_profile_url'])) > 0)) &&
(isset($_POST['launch_presentation_return_url']) && (strlen(trim($_POST['launch_presentation_return_url'])) > 0)));
if ($this->debugMode && !$this->ok) {
$this->reason = 'Missing message parameters.';
}
}
}
$now = time();
// Check consumer key
if ($this->ok && ($_POST['lti_message_type'] != 'ToolProxyRegistrationRequest')) {
$this->ok = isset($_POST['oauth_consumer_key']);
if (!$this->ok) {
$this->reason = 'Missing consumer key.';
}
if ($this->ok) {
$this->consumer = new ToolConsumer($_POST['oauth_consumer_key'], $this->dataConnector);
$this->ok = !is_null($this->consumer->created);
if (!$this->ok) {
$this->reason = 'Invalid consumer key.';
}
}
if ($this->ok) {
$today = date('Y-m-d', $now);
if (is_null($this->consumer->lastAccess)) {
$doSaveConsumer = true;
} else {
$last = date('Y-m-d', $this->consumer->lastAccess);
$doSaveConsumer = $doSaveConsumer || ($last !== $today);
}
$this->consumer->lastAccess = $now;
try {
$store = new OAuthDataStore($this);
$server = new OAuth\OAuthServer($store);
$method = new OAuth\OAuthSignatureMethod_HMAC_SHA1();
$server->add_signature_method($method);
$request = OAuth\OAuthRequest::from_request();
$res = $server->verify_request($request);
} catch (\Exception $e) {
$this->ok = false;
if (empty($this->reason)) {
if ($this->debugMode) {
$consumer = new OAuth\OAuthConsumer($this->consumer->getKey(), $this->consumer->secret);
$signature = $request->build_signature($method, $consumer, false);
$this->reason = $e->getMessage();
if (empty($this->reason)) {
$this->reason = 'OAuth exception';
}
$this->details[] = 'Timestamp: ' . time();
$this->details[] = "Signature: {$signature}";
$this->details[] = "Base string: {$request->base_string}]";
} else {
$this->reason = 'OAuth signature check failed - perhaps an incorrect secret or timestamp.';
}
}
}
}
if ($this->ok) {
$today = date('Y-m-d', $now);
if (is_null($this->consumer->lastAccess)) {
$doSaveConsumer = true;
} else {
$last = date('Y-m-d', $this->consumer->lastAccess);
$doSaveConsumer = $doSaveConsumer || ($last !== $today);
}
$this->consumer->lastAccess = $now;
if ($this->consumer->protected) {
if (!is_null($this->consumer->consumerGuid)) {
$this->ok = empty($_POST['tool_consumer_instance_guid']) ||
($this->consumer->consumerGuid === $_POST['tool_consumer_instance_guid']);
if (!$this->ok) {
$this->reason = 'Request is from an invalid tool consumer.';
}
} else {
$this->ok = isset($_POST['tool_consumer_instance_guid']);
if (!$this->ok) {
$this->reason = 'A tool consumer GUID must be included in the launch request.';
}
}
}
if ($this->ok) {
$this->ok = $this->consumer->enabled;
if (!$this->ok) {
$this->reason = 'Tool consumer has not been enabled by the tool provider.';
}
}
if ($this->ok) {
$this->ok = is_null($this->consumer->enableFrom) || ($this->consumer->enableFrom <= $now);
if ($this->ok) {
$this->ok = is_null($this->consumer->enableUntil) || ($this->consumer->enableUntil > $now);
if (!$this->ok) {
$this->reason = 'Tool consumer access has expired.';
}
} else {
$this->reason = 'Tool consumer access is not yet available.';
}
}
}
// Validate other message parameter values
if ($this->ok) {
if ($_POST['lti_message_type'] === 'ContentItemSelectionRequest') {
if (isset($_POST['accept_unsigned'])) {
$this->ok = $this->checkValue($_POST['accept_unsigned'], array('true', 'false'), 'Invalid value for accept_unsigned parameter: %s.');
}
if ($this->ok && isset($_POST['accept_multiple'])) {
$this->ok = $this->checkValue($_POST['accept_multiple'], array('true', 'false'), 'Invalid value for accept_multiple parameter: %s.');
}
if ($this->ok && isset($_POST['accept_copy_advice'])) {
$this->ok = $this->checkValue($_POST['accept_copy_advice'], array('true', 'false'), 'Invalid value for accept_copy_advice parameter: %s.');
}
if ($this->ok && isset($_POST['auto_create'])) {
$this->ok = $this->checkValue($_POST['auto_create'], array('true', 'false'), 'Invalid value for auto_create parameter: %s.');
}
if ($this->ok && isset($_POST['can_confirm'])) {
$this->ok = $this->checkValue($_POST['can_confirm'], array('true', 'false'), 'Invalid value for can_confirm parameter: %s.');
}
} else if (isset($_POST['launch_presentation_document_target'])) {
$this->ok = $this->checkValue($_POST['launch_presentation_document_target'], array('embed', 'frame', 'iframe', 'window', 'popup', 'overlay'),
'Invalid value for launch_presentation_document_target parameter: %s.');
}
}
}
if ($this->ok && ($_POST['lti_message_type'] === 'ToolProxyRegistrationRequest')) {
$this->ok = $_POST['lti_version'] == self::LTI_VERSION2;
if (!$this->ok) {
$this->reason = 'Invalid lti_version parameter';
}
if ($this->ok) {
$http = new HTTPMessage($_POST['tc_profile_url'], 'GET', null, 'Accept: application/vnd.ims.lti.v2.toolconsumerprofile+json');
$this->ok = $http->send();
if (!$this->ok) {
$this->reason = 'Tool consumer profile not accessible.';
} else {
$tcProfile = json_decode($http->response);
$this->ok = !is_null($tcProfile);
if (!$this->ok) {
$this->reason = 'Invalid JSON in tool consumer profile.';
}
}
}
// Check for required capabilities
if ($this->ok) {
$this->consumer = new ToolConsumer($_POST['reg_key'], $this->dataConnector);
$this->consumer->profile = $tcProfile;
$capabilities = $this->consumer->profile->capability_offered;
$missing = array();
foreach ($this->resourceHandlers as $resourceHandler) {
foreach ($resourceHandler->requiredMessages as $message) {
if (!in_array($message->type, $capabilities)) {
$missing[$message->type] = true;
}
}
}
foreach ($this->constraints as $name => $constraint) {
if ($constraint['required']) {
if (!in_array($name, $capabilities) && !in_array($name, array_flip($capabilities))) {
$missing[$name] = true;
}
}
}
if (!empty($missing)) {
ksort($missing);
$this->reason = 'Required capability not offered - \'' . implode('\', \'', array_keys($missing)) . '\'';
$this->ok = false;
}
}
// Check for required services
if ($this->ok) {
foreach ($this->requiredServices as $service) {
foreach ($service->formats as $format) {
if (!$this->findService($format, $service->actions)) {
if ($this->ok) {
$this->reason = 'Required service(s) not offered - ';
$this->ok = false;
} else {
$this->reason .= ', ';
}
$this->reason .= "'{$format}' [" . implode(', ', $service->actions) . ']';
}
}
}
}
if ($this->ok) {
if ($_POST['lti_message_type'] === 'ToolProxyRegistrationRequest') {
$this->consumer->profile = $tcProfile;
$this->consumer->secret = $_POST['reg_password'];
$this->consumer->ltiVersion = $_POST['lti_version'];
$this->consumer->name = $tcProfile->product_instance->service_owner->service_owner_name->default_value;
$this->consumer->consumerName = $this->consumer->name;
$this->consumer->consumerVersion = "{$tcProfile->product_instance->product_info->product_family->code}-{$tcProfile->product_instance->product_info->product_version}";
$this->consumer->consumerGuid = $tcProfile->product_instance->guid;
$this->consumer->enabled = true;
$this->consumer->protected = true;
$doSaveConsumer = true;
}
}
} else if ($this->ok && !empty($_POST['custom_tc_profile_url']) && empty($this->consumer->profile)) {
$http = new HTTPMessage($_POST['custom_tc_profile_url'], 'GET', null, 'Accept: application/vnd.ims.lti.v2.toolconsumerprofile+json');
if ($http->send()) {
$tcProfile = json_decode($http->response);
if (!is_null($tcProfile)) {
$this->consumer->profile = $tcProfile;
$doSaveConsumer = true;
}
}
}
// Validate message parameter constraints
if ($this->ok) {
$invalidParameters = array();
foreach ($this->constraints as $name => $constraint) {
if (empty($constraint['messages']) || in_array($_POST['lti_message_type'], $constraint['messages'])) {
$ok = true;
if ($constraint['required']) {
if (!isset($_POST[$name]) || (strlen(trim($_POST[$name])) <= 0)) {
$invalidParameters[] = "{$name} (missing)";
$ok = false;
}
}
if ($ok && !is_null($constraint['max_length']) && isset($_POST[$name])) {
if (strlen(trim($_POST[$name])) > $constraint['max_length']) {
$invalidParameters[] = "{$name} (too long)";
}
}
}
}
if (count($invalidParameters) > 0) {
$this->ok = false;
if (empty($this->reason)) {
$this->reason = 'Invalid parameter(s): ' . implode(', ', $invalidParameters) . '.';
}
}
}
if ($this->ok) {
// Set the request context
if (isset($_POST['context_id'])) {
$this->context = Context::fromConsumer($this->consumer, trim($_POST['context_id']));
$title = '';
if (isset($_POST['context_title'])) {
$title = trim($_POST['context_title']);
}
if (empty($title)) {
$title = "Course {$this->context->getId()}";
}
$this->context->title = $title;
}
// Set the request resource link
if (isset($_POST['resource_link_id'])) {
$contentItemId = '';