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Differences Between: [Versions 310 and 401] [Versions 311 and 401] [Versions 39 and 401]

   1  <?php
   2  // This file is part of Moodle - http://moodle.org/
   3  //
   4  // Moodle is free software: you can redistribute it and/or modify
   5  // it under the terms of the GNU General Public License as published by
   6  // the Free Software Foundation, either version 3 of the License, or
   7  // (at your option) any later version.
   8  //
   9  // Moodle is distributed in the hope that it will be useful,
  10  // but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12  // GNU General Public License for more details.
  13  //
  14  // You should have received a copy of the GNU General Public License
  15  // along with Moodle.  If not, see <http://www.gnu.org/licenses/>.
  16  
  17  /**
  18   * Handles synchronising members using the enrolment LTI.
  19   *
  20   * @package    enrol_lti
  21   * @copyright  2016 Mark Nelson <markn@moodle.com>
  22   * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
  23   */
  24  
  25  namespace enrol_lti\task;
  26  
  27  defined('MOODLE_INTERNAL') || die();
  28  
  29  use core\task\scheduled_task;
  30  use core_user;
  31  use enrol_lti\data_connector;
  32  use enrol_lti\helper;
  33  use IMSGlobal\LTI\ToolProvider\Context;
  34  use IMSGlobal\LTI\ToolProvider\ResourceLink;
  35  use IMSGlobal\LTI\ToolProvider\ToolConsumer;
  36  use IMSGlobal\LTI\ToolProvider\User;
  37  use stdClass;
  38  
  39  require_once($CFG->dirroot . '/user/lib.php');
  40  
  41  /**
  42   * Task for synchronising members using the enrolment LTI.
  43   *
  44   * @package    enrol_lti
  45   * @copyright  2016 Mark Nelson <markn@moodle.com>
  46   * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
  47   */
  48  class sync_members extends scheduled_task {
  49  
  50      /** @var array Array of user photos. */
  51      protected $userphotos = [];
  52  
  53      /** @var data_connector $dataconnector A data_connector instance. */
  54      protected $dataconnector;
  55  
  56      /**
  57       * Get a descriptive name for this task.
  58       *
  59       * @return string
  60       */
  61      public function get_name() {
  62          return get_string('tasksyncmembers', 'enrol_lti');
  63      }
  64  
  65      /**
  66       * Performs the synchronisation of members.
  67       */
  68      public function execute() {
  69          if (!is_enabled_auth('lti')) {
  70              mtrace('Skipping task - ' . get_string('pluginnotenabled', 'auth', get_string('pluginname', 'auth_lti')));
  71              return;
  72          }
  73  
  74          // Check if the enrolment plugin is disabled - isn't really necessary as the task should not run if
  75          // the plugin is disabled, but there is no harm in making sure core hasn't done something wrong.
  76          if (!enrol_is_enabled('lti')) {
  77              mtrace('Skipping task - ' . get_string('enrolisdisabled', 'enrol_lti'));
  78              return;
  79          }
  80  
  81          $this->dataconnector = new data_connector();
  82  
  83          // Get all the enabled tools.
  84          $tools = helper::get_lti_tools(array('status' => ENROL_INSTANCE_ENABLED, 'membersync' => 1,
  85              'ltiversion' => 'LTI-1p0/LTI-2p0'));
  86          foreach ($tools as $tool) {
  87              mtrace("Starting - Member sync for published tool '$tool->id' for course '$tool->courseid'.");
  88  
  89              // Variables to keep track of information to display later.
  90              $usercount = 0;
  91              $enrolcount = 0;
  92              $unenrolcount = 0;
  93  
  94              // Fetch consumer records mapped to this tool.
  95              $consumers = $this->dataconnector->get_consumers_mapped_to_tool($tool->id);
  96  
  97              // Perform processing for each consumer.
  98              foreach ($consumers as $consumer) {
  99                  mtrace("Requesting membership service for the tool consumer '{$consumer->getRecordId()}'");
 100  
 101                  // Get members through this tool consumer.
 102                  $members = $this->fetch_members_from_consumer($consumer);
 103  
 104                  // Check if we were able to fetch the members.
 105                  if ($members === false) {
 106                      mtrace("Skipping - Membership service request failed.\n");
 107                      continue;
 108                  }
 109  
 110                  // Fetched members count.
 111                  $membercount = count($members);
 112                  $usercount += $membercount;
 113                  mtrace("$membercount members received.\n");
 114  
 115                  // Process member information.
 116                  list($users, $enrolledcount) = $this->sync_member_information($tool, $consumer, $members);
 117                  $enrolcount += $enrolledcount;
 118  
 119                  // Now sync unenrolments for the consumer.
 120                  $unenrolcount += $this->sync_unenrol($tool, $consumer->getKey(), $users);
 121              }
 122  
 123              mtrace("Completed - Synced members for tool '$tool->id' in the course '$tool->courseid'. " .
 124                   "Processed $usercount users; enrolled $enrolcount members; unenrolled $unenrolcount members.\n");
 125          }
 126  
 127          // Sync the user profile photos.
 128          mtrace("Started - Syncing user profile images.");
 129          $countsyncedimages = $this->sync_profile_images();
 130          mtrace("Completed - Synced $countsyncedimages profile images.");
 131      }
 132  
 133      /**
 134       * Fetches the members that belong to a ToolConsumer.
 135       *
 136       * @param ToolConsumer $consumer
 137       * @return bool|User[]
 138       */
 139      protected function fetch_members_from_consumer(ToolConsumer $consumer) {
 140          $dataconnector = $this->dataconnector;
 141  
 142          // Get membership URL template from consumer profile data.
 143          $defaultmembershipsurl = null;
 144          if (isset($consumer->profile->service_offered)) {
 145              $servicesoffered = $consumer->profile->service_offered;
 146              foreach ($servicesoffered as $service) {
 147                  if (isset($service->{'@id'}) && strpos($service->{'@id'}, 'tcp:ToolProxyBindingMemberships') !== false &&
 148                      isset($service->endpoint)) {
 149                      $defaultmembershipsurl = $service->endpoint;
 150                      if (isset($consumer->profile->product_instance->product_info->product_family->vendor->code)) {
 151                          $vendorcode = $consumer->profile->product_instance->product_info->product_family->vendor->code;
 152                          $defaultmembershipsurl = str_replace('{vendor_code}', $vendorcode, $defaultmembershipsurl);
 153                      }
 154                      $defaultmembershipsurl = str_replace('{product_code}', $consumer->getKey(), $defaultmembershipsurl);
 155                      break;
 156                  }
 157              }
 158          }
 159  
 160          $members = false;
 161  
 162          // Fetch the resource link linked to the consumer.
 163          $resourcelink = $dataconnector->get_resourcelink_from_consumer($consumer);
 164          if ($resourcelink !== null) {
 165              // Try to perform a membership service request using this resource link.
 166              $members = $this->do_resourcelink_membership_request($resourcelink);
 167          }
 168  
 169          // If membership service can't be performed through resource link, fallback through context memberships.
 170          if ($members === false) {
 171              // Fetch context records that are mapped to this ToolConsumer.
 172              $contexts = $dataconnector->get_contexts_from_consumer($consumer);
 173  
 174              // Perform membership service request for each of these contexts.
 175              foreach ($contexts as $context) {
 176                  $contextmembership = $this->do_context_membership_request($context, $resourcelink, $defaultmembershipsurl);
 177                  if ($contextmembership) {
 178                      // Add $contextmembership contents to $members array.
 179                      if (is_array($members)) {
 180                          $members = array_merge($members, $contextmembership);
 181                      } else {
 182                          $members = $contextmembership;
 183                      }
 184                  }
 185              }
 186          }
 187  
 188          return $members;
 189      }
 190  
 191      /**
 192       * Method to determine whether to sync unenrolments or not.
 193       *
 194       * @param int $syncmode The tool's membersyncmode.
 195       * @return bool
 196       */
 197      protected function should_sync_unenrol($syncmode) {
 198          return $syncmode == helper::MEMBER_SYNC_ENROL_AND_UNENROL || $syncmode == helper::MEMBER_SYNC_UNENROL_MISSING;
 199      }
 200  
 201      /**
 202       * Method to determine whether to sync enrolments or not.
 203       *
 204       * @param int $syncmode The tool's membersyncmode.
 205       * @return bool
 206       */
 207      protected function should_sync_enrol($syncmode) {
 208          return $syncmode == helper::MEMBER_SYNC_ENROL_AND_UNENROL || $syncmode == helper::MEMBER_SYNC_ENROL_NEW;
 209      }
 210  
 211      /**
 212       * Performs synchronisation of member information and enrolments.
 213       *
 214       * @param stdClass $tool
 215       * @param ToolConsumer $consumer
 216       * @param User[] $members
 217       * @return array An array of users from processed members and the number that were enrolled.
 218       */
 219      protected function sync_member_information(stdClass $tool, ToolConsumer $consumer, $members) {
 220          global $DB;
 221          $users = [];
 222          $enrolcount = 0;
 223  
 224          // Process member information.
 225          foreach ($members as $member) {
 226              // Set the user data.
 227              $user = new stdClass();
 228              $user->username = helper::create_username($consumer->getKey(), $member->ltiUserId);
 229              $user->firstname = core_user::clean_field($member->firstname, 'firstname');
 230              $user->lastname = core_user::clean_field($member->lastname, 'lastname');
 231              $user->email = core_user::clean_field($member->email, 'email');
 232  
 233              // Get the user data from the LTI consumer.
 234              $user = helper::assign_user_tool_data($tool, $user);
 235  
 236              $dbuser = core_user::get_user_by_username($user->username, 'id');
 237              if ($dbuser) {
 238                  // If email is empty remove it, so we don't update the user with an empty email.
 239                  if (empty($user->email)) {
 240                      unset($user->email);
 241                  }
 242  
 243                  $user->id = $dbuser->id;
 244                  user_update_user($user);
 245  
 246                  // Add the information to the necessary arrays.
 247                  $users[$user->id] = $user;
 248                  $this->userphotos[$user->id] = $member->image;
 249              } else {
 250                  if ($this->should_sync_enrol($tool->membersyncmode)) {
 251                      // If the email was stripped/not set then fill it with a default one. This
 252                      // stops the user from being redirected to edit their profile page.
 253                      if (empty($user->email)) {
 254                          $user->email = $user->username .  "@example.com";
 255                      }
 256  
 257                      $user->auth = 'lti';
 258                      $user->id = user_create_user($user);
 259  
 260                      // Add the information to the necessary arrays.
 261                      $users[$user->id] = $user;
 262                      $this->userphotos[$user->id] = $member->image;
 263                  }
 264              }
 265  
 266              // Sync enrolments.
 267              if ($this->should_sync_enrol($tool->membersyncmode)) {
 268                  // Enrol the user in the course.
 269                  if (helper::enrol_user($tool, $user->id) === helper::ENROLMENT_SUCCESSFUL) {
 270                      // Increment enrol count.
 271                      $enrolcount++;
 272                  }
 273  
 274                  // Check if this user has already been registered in the enrol_lti_users table.
 275                  if (!$DB->record_exists('enrol_lti_users', ['toolid' => $tool->id, 'userid' => $user->id])) {
 276                      // Create an initial enrol_lti_user record that we can use later when syncing grades and members.
 277                      $userlog = new stdClass();
 278                      $userlog->userid = $user->id;
 279                      $userlog->toolid = $tool->id;
 280                      $userlog->consumerkey = $consumer->getKey();
 281  
 282                      $DB->insert_record('enrol_lti_users', $userlog);
 283                  }
 284              }
 285          }
 286  
 287          return [$users, $enrolcount];
 288      }
 289  
 290      /**
 291       * Performs unenrolment of users that are no longer enrolled in the consumer side.
 292       *
 293       * @param stdClass $tool The tool record object.
 294       * @param string $consumerkey ensure we only unenrol users from this tool consumer.
 295       * @param array $currentusers The list of current users.
 296       * @return int The number of users that have been unenrolled.
 297       */
 298      protected function sync_unenrol(stdClass $tool, string $consumerkey, array $currentusers) {
 299          global $DB;
 300  
 301          $ltiplugin = enrol_get_plugin('lti');
 302  
 303          if (!$this->should_sync_unenrol($tool->membersyncmode)) {
 304              return 0;
 305          }
 306  
 307          if (empty($currentusers)) {
 308              return 0;
 309          }
 310  
 311          $unenrolcount = 0;
 312  
 313          $select = "toolid = :toolid AND " . $DB->sql_compare_text('consumerkey', 255) . " = :consumerkey";
 314          $ltiusersrs = $DB->get_recordset_select('enrol_lti_users', $select, ['toolid' => $tool->id, 'consumerkey' => $consumerkey],
 315              'lastaccess DESC', 'userid');
 316          // Go through the users and check if any were never listed, if so, remove them.
 317          foreach ($ltiusersrs as $ltiuser) {
 318              if (!array_key_exists($ltiuser->userid, $currentusers)) {
 319                  $instance = new stdClass();
 320                  $instance->id = $tool->enrolid;
 321                  $instance->courseid = $tool->courseid;
 322                  $instance->enrol = 'lti';
 323                  $ltiplugin->unenrol_user($instance, $ltiuser->userid);
 324                  // Increment unenrol count.
 325                  $unenrolcount++;
 326              }
 327          }
 328          $ltiusersrs->close();
 329  
 330          return $unenrolcount;
 331      }
 332  
 333      /**
 334       * Performs synchronisation of user profile images.
 335       */
 336      protected function sync_profile_images() {
 337          $counter = 0;
 338          foreach ($this->userphotos as $userid => $url) {
 339              if ($url) {
 340                  $result = helper::update_user_profile_image($userid, $url);
 341                  if ($result === helper::PROFILE_IMAGE_UPDATE_SUCCESSFUL) {
 342                      $counter++;
 343                      mtrace("Profile image succesfully downloaded and created for user '$userid' from $url.");
 344                  } else {
 345                      mtrace($result);
 346                  }
 347              }
 348          }
 349          return $counter;
 350      }
 351  
 352      /**
 353       * Performs membership service request using an LTI Context object.
 354       *
 355       * If the context has a 'custom_context_memberships_url' setting, we use this to perform the membership service request.
 356       * Otherwise, if a context is associated with resource link, we try first to get the members using the
 357       * ResourceLink::doMembershipsService() method.
 358       * If we're still unable to fetch members from the resource link, we try to build a memberships URL from the memberships URL
 359       * endpoint template that is defined in the ToolConsumer profile and substitute the parameters accordingly.
 360       *
 361       * @param Context $context The context object.
 362       * @param ResourceLink $resourcelink The resource link object.
 363       * @param string $membershipsurltemplate The memberships endpoint URL template.
 364       * @return bool|User[] Array of User objects upon successful membership service request. False, otherwise.
 365       */
 366      protected function do_context_membership_request(Context $context, ResourceLink $resourcelink = null,
 367                                                       $membershipsurltemplate = '') {
 368          $dataconnector = $this->dataconnector;
 369  
 370          // Flag to indicate whether to save the context later.
 371          $contextupdated = false;
 372  
 373          // If membership URL is not set, try to generate using the default membership URL from the consumer profile.
 374          if (!$context->hasMembershipService()) {
 375              if (empty($membershipsurltemplate)) {
 376                  mtrace("Skipping - No membership service available.\n");
 377                  return false;
 378              }
 379  
 380              if ($resourcelink === null) {
 381                  $resourcelink = $dataconnector->get_resourcelink_from_context($context);
 382              }
 383  
 384              if ($resourcelink !== null) {
 385                  // Try to perform a membership service request using this resource link.
 386                  $resourcelinkmembers = $this->do_resourcelink_membership_request($resourcelink);
 387                  if ($resourcelinkmembers) {
 388                      // If we're able to fetch members using this resource link, return these.
 389                      return $resourcelinkmembers;
 390                  }
 391              }
 392  
 393              // If fetching memberships through resource link failed and we don't have a memberships URL, build one from template.
 394              mtrace("'custom_context_memberships_url' not set. Fetching default template: $membershipsurltemplate");
 395              $membershipsurl = $membershipsurltemplate;
 396  
 397              // Check if we need to fetch tool code.
 398              $needstoolcode = strpos($membershipsurl, '{tool_code}') !== false;
 399              if ($needstoolcode) {
 400                  $toolcode = false;
 401  
 402                  // Fetch tool code from the resource link data.
 403                  $lisresultsourcedidjson = $resourcelink->getSetting('lis_result_sourcedid');
 404                  if ($lisresultsourcedidjson) {
 405                      $lisresultsourcedid = json_decode($lisresultsourcedidjson);
 406                      if (isset($lisresultsourcedid->data->typeid)) {
 407                          $toolcode = $lisresultsourcedid->data->typeid;
 408                      }
 409                  }
 410  
 411                  if ($toolcode) {
 412                      // Substitute fetched tool code value.
 413                      $membershipsurl = str_replace('{tool_code}', $toolcode, $membershipsurl);
 414                  } else {
 415                      // We're unable to determine the tool code. End this processing.
 416                      return false;
 417                  }
 418              }
 419  
 420              // Get context_id parameter and substitute, if applicable.
 421              $membershipsurl = str_replace('{context_id}', $context->getId(), $membershipsurl);
 422  
 423              // Get context_type and substitute, if applicable.
 424              if (strpos($membershipsurl, '{context_type}') !== false) {
 425                  $contexttype = $context->type !== null ? $context->type : 'CourseSection';
 426                  $membershipsurl = str_replace('{context_type}', $contexttype, $membershipsurl);
 427              }
 428  
 429              // Save this URL for the context's custom_context_memberships_url setting.
 430              $context->setSetting('custom_context_memberships_url', $membershipsurl);
 431              $contextupdated = true;
 432          }
 433  
 434          // Perform membership service request.
 435          $url = $context->getSetting('custom_context_memberships_url');
 436          mtrace("Performing membership service request from context with URL {$url}.");
 437          $members = $context->getMembership();
 438  
 439          // Save the context if membership request succeeded and if it has been updated.
 440          if ($members && $contextupdated) {
 441              $context->save();
 442          }
 443  
 444          return $members;
 445      }
 446  
 447      /**
 448       * Performs membership service request using ResourceLink::doMembershipsService() method.
 449       *
 450       * @param ResourceLink $resourcelink
 451       * @return bool|User[] Array of User objects upon successful membership service request. False, otherwise.
 452       */
 453      protected function do_resourcelink_membership_request(ResourceLink $resourcelink) {
 454          $members = false;
 455          $membershipsurl = $resourcelink->getSetting('ext_ims_lis_memberships_url');
 456          $membershipsid = $resourcelink->getSetting('ext_ims_lis_memberships_id');
 457          if ($membershipsurl && $membershipsid) {
 458              mtrace("Performing membership service request from resource link with membership URL: " . $membershipsurl);
 459              $members = $resourcelink->doMembershipsService(true);
 460          }
 461          return $members;
 462      }
 463  }