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Differences Between: [Versions 311 and 401] [Versions 311 and 402] [Versions 311 and 403]

   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   * Class to manage subscriptions.
  19   *
  20   * @package    tool_monitor
  21   * @copyright  2014 onwards Ankit Agarwal <ankit.agrr@gmail.com>
  22   * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
  23   */
  24  
  25  namespace tool_monitor;
  26  
  27  defined('MOODLE_INTERNAL') || die();
  28  
  29  /**
  30   * Class to manage subscriptions.
  31   *
  32   * @since      Moodle 2.8
  33   * @package    tool_monitor
  34   * @copyright  2014 onwards Ankit Agarwal <ankit.agrr@gmail.com>
  35   * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
  36   */
  37  class subscription_manager {
  38  
  39      /** @const Period of time, in days, after which an inactive subscription will be removed completely.*/
  40      const INACTIVE_SUBSCRIPTION_LIFESPAN_IN_DAYS = 30;
  41  
  42      /**
  43       * Subscribe a user to a given rule.
  44       *
  45       * @param int $ruleid  Rule id.
  46       * @param int $courseid Course id.
  47       * @param int $cmid Course module id.
  48       * @param int $userid User who is subscribing, defaults to $USER.
  49       *
  50       * @return bool|int returns id of the created subscription.
  51       */
  52      public static function create_subscription($ruleid, $courseid, $cmid, $userid = 0) {
  53          global $DB, $USER;
  54  
  55          $subscription = new \stdClass();
  56          $subscription->ruleid = $ruleid;
  57          $subscription->courseid = $courseid;
  58          $subscription->cmid = $cmid;
  59          $subscription->userid = empty($userid) ? $USER->id : $userid;
  60          if ($DB->record_exists('tool_monitor_subscriptions', (array)$subscription)) {
  61              // Subscription already exists.
  62              return false;
  63          }
  64  
  65          $subscription->timecreated = time();
  66          $subscription->id = $DB->insert_record('tool_monitor_subscriptions', $subscription);
  67  
  68          // Trigger a subscription created event.
  69          if ($subscription->id) {
  70              if (!empty($subscription->courseid)) {
  71                  $courseid = $subscription->courseid;
  72                  $context = \context_course::instance($subscription->courseid);
  73              } else {
  74                  $courseid = 0;
  75                  $context = \context_system::instance();
  76              }
  77  
  78              $params = array(
  79                  'objectid' => $subscription->id,
  80                  'courseid' => $courseid,
  81                  'context' => $context
  82              );
  83              $event = \tool_monitor\event\subscription_created::create($params);
  84              $event->trigger();
  85  
  86              // Let's invalidate the cache.
  87              $cache = \cache::make('tool_monitor', 'eventsubscriptions');
  88              $cache->delete($courseid);
  89          }
  90  
  91          return $subscription->id;
  92      }
  93  
  94      /**
  95       * Delete a subscription.
  96       *
  97       * @param subscription|int $subscriptionorid an instance of subscription class or id.
  98       * @param bool $checkuser Check if the subscription belongs to current user before deleting.
  99       *
 100       * @return bool
 101       * @throws \coding_exception if $checkuser is true and the subscription doesn't belong to the current user.
 102       */
 103      public static function delete_subscription($subscriptionorid, $checkuser = true) {
 104          global $DB, $USER;
 105          if (is_object($subscriptionorid)) {
 106              $subscription = $subscriptionorid;
 107          } else {
 108              $subscription = self::get_subscription($subscriptionorid);
 109          }
 110          if ($checkuser && $subscription->userid != $USER->id) {
 111              throw new \coding_exception('Invalid subscription supplied');
 112          }
 113  
 114          // Store the subscription before we delete it.
 115          $subscription = $DB->get_record('tool_monitor_subscriptions', array('id' => $subscription->id));
 116  
 117          $success = $DB->delete_records('tool_monitor_subscriptions', array('id' => $subscription->id));
 118  
 119          // If successful trigger a subscription_deleted event.
 120          if ($success) {
 121              if (!empty($subscription->courseid) &&
 122                      ($coursecontext = \context_course::instance($subscription->courseid, IGNORE_MISSING))) {
 123                  $courseid = $subscription->courseid;
 124                  $context = $coursecontext;
 125              } else {
 126                  $courseid = 0;
 127                  $context = \context_system::instance();
 128              }
 129  
 130              $params = array(
 131                  'objectid' => $subscription->id,
 132                  'courseid' => $courseid,
 133                  'context' => $context
 134              );
 135              $event = \tool_monitor\event\subscription_deleted::create($params);
 136              $event->add_record_snapshot('tool_monitor_subscriptions', $subscription);
 137              $event->trigger();
 138  
 139              // Let's invalidate the cache.
 140              $cache = \cache::make('tool_monitor', 'eventsubscriptions');
 141              $cache->delete($courseid);
 142          }
 143  
 144          return $success;
 145      }
 146  
 147      /**
 148       * Delete all subscriptions for a user.
 149       *
 150       * @param int $userid user id.
 151       *
 152       * @return mixed
 153       */
 154      public static function delete_user_subscriptions($userid) {
 155          global $DB;
 156          return $DB->delete_records('tool_monitor_subscriptions', array('userid' => $userid));
 157      }
 158  
 159      /**
 160       * Delete all subscriptions for a course module.
 161       *
 162       * @param int $cmid cm id.
 163       *
 164       * @return mixed
 165       */
 166      public static function delete_cm_subscriptions($cmid) {
 167          global $DB;
 168          return $DB->delete_records('tool_monitor_subscriptions', array('cmid' => $cmid));
 169      }
 170  
 171      /**
 172       * Delete all subscribers for a given rule.
 173       *
 174       * @param int $ruleid rule id.
 175       * @param \context|null $coursecontext the context of the course - this is passed when we
 176       *      can not get the context via \context_course as the course has been deleted.
 177       *
 178       * @return bool
 179       */
 180      public static function remove_all_subscriptions_for_rule($ruleid, $coursecontext = null) {
 181          global $DB;
 182  
 183          // Store all the subscriptions we have to delete.
 184          $subscriptions = $DB->get_recordset('tool_monitor_subscriptions', array('ruleid' => $ruleid));
 185  
 186          // Now delete them.
 187          $success = $DB->delete_records('tool_monitor_subscriptions', array('ruleid' => $ruleid));
 188  
 189          // If successful and there were subscriptions that were deleted trigger a subscription deleted event.
 190          if ($success && $subscriptions) {
 191              foreach ($subscriptions as $subscription) {
 192                  // It is possible that we are deleting rules associated with a deleted course, so we should be
 193                  // passing the context as the second parameter.
 194                  if (!is_null($coursecontext)) {
 195                      $context = $coursecontext;
 196                      $courseid = $subscription->courseid;
 197                  } else if (!empty($subscription->courseid) && ($coursecontext =
 198                          \context_course::instance($subscription->courseid, IGNORE_MISSING))) {
 199                      $courseid = $subscription->courseid;
 200                      $context = $coursecontext;
 201                  } else {
 202                      $courseid = 0;
 203                      $context = \context_system::instance();
 204                  }
 205  
 206                  $params = array(
 207                      'objectid' => $subscription->id,
 208                      'courseid' => $courseid,
 209                      'context' => $context
 210                  );
 211                  $event = \tool_monitor\event\subscription_deleted::create($params);
 212                  $event->add_record_snapshot('tool_monitor_subscriptions', $subscription);
 213                  $event->trigger();
 214  
 215                  // Let's invalidate the cache.
 216                  $cache = \cache::make('tool_monitor', 'eventsubscriptions');
 217                  $cache->delete($courseid);
 218              }
 219          }
 220  
 221          $subscriptions->close();
 222  
 223          return $success;
 224      }
 225  
 226      /**
 227       * Delete all subscriptions in a course.
 228       *
 229       * This is called after a course was deleted, context no longer exists but we kept the object
 230       *
 231       * @param \context_course $coursecontext the context of the course
 232       */
 233      public static function remove_all_subscriptions_in_course($coursecontext) {
 234          global $DB;
 235  
 236          // Store all the subscriptions we have to delete.
 237          if ($subscriptions = $DB->get_records('tool_monitor_subscriptions', ['courseid' => $coursecontext->instanceid])) {
 238              // Delete subscriptions in bulk.
 239              $DB->delete_records('tool_monitor_subscriptions', ['courseid' => $coursecontext->instanceid]);
 240  
 241              // Trigger events one by one.
 242              foreach ($subscriptions as $subscription) {
 243                  $params = ['objectid' => $subscription->id, 'context' => $coursecontext];
 244                  $event = \tool_monitor\event\subscription_deleted::create($params);
 245                  $event->add_record_snapshot('tool_monitor_subscriptions', $subscription);
 246                  $event->trigger();
 247              }
 248          }
 249      }
 250  
 251      /**
 252       * Get a subscription instance for an given subscription id.
 253       *
 254       * @param subscription|int $subscriptionorid an instance of subscription class or id.
 255       *
 256       * @return subscription returns a instance of subscription class.
 257       */
 258      public static function get_subscription($subscriptionorid) {
 259          global $DB;
 260  
 261          if (is_object($subscriptionorid)) {
 262              return new subscription($subscriptionorid);
 263          }
 264  
 265          $sql = self::get_subscription_join_rule_sql();
 266          $sql .= "WHERE s.id = :id";
 267          $sub = $DB->get_record_sql($sql, array('id' => $subscriptionorid), MUST_EXIST);
 268          return new subscription($sub);
 269      }
 270  
 271      /**
 272       * Get an array of subscriptions for a given user in a given course.
 273       *
 274       * @param int $courseid course id.
 275       * @param int $limitfrom Limit from which to fetch rules.
 276       * @param int $limitto  Limit to which rules need to be fetched.
 277       * @param int $userid Id of the user for which the subscription needs to be fetched. Defaults to $USER;
 278       * @param string $order Order to sort the subscriptions.
 279       *
 280       * @return array list of subscriptions
 281       */
 282      public static function get_user_subscriptions_for_course($courseid, $limitfrom = 0, $limitto = 0, $userid = 0,
 283              $order = 's.timecreated DESC' ) {
 284          global $DB, $USER;
 285          if ($userid == 0) {
 286              $userid = $USER->id;
 287          }
 288          $sql = self::get_subscription_join_rule_sql();
 289          $sql .= "WHERE s.courseid = :courseid AND s.userid = :userid ORDER BY $order";
 290  
 291          return self::get_instances($DB->get_records_sql($sql, array('courseid' => $courseid, 'userid' => $userid), $limitfrom,
 292                  $limitto));
 293      }
 294  
 295      /**
 296       * Get count of subscriptions for a given user in a given course.
 297       *
 298       * @param int $courseid course id.
 299       * @param int $userid Id of the user for which the subscription needs to be fetched. Defaults to $USER;
 300       *
 301       * @return int number of subscriptions
 302       */
 303      public static function count_user_subscriptions_for_course($courseid, $userid = 0) {
 304          global $DB, $USER;
 305          if ($userid == 0) {
 306              $userid = $USER->id;
 307          }
 308          $sql = self::get_subscription_join_rule_sql(true);
 309          $sql .= "WHERE s.courseid = :courseid AND s.userid = :userid";
 310  
 311          return $DB->count_records_sql($sql, array('courseid' => $courseid, 'userid' => $userid));
 312      }
 313  
 314      /**
 315       * Get an array of subscriptions for a given user.
 316       *
 317       * @param int $limitfrom Limit from which to fetch rules.
 318       * @param int $limitto  Limit to which rules need to be fetched.
 319       * @param int $userid Id of the user for which the subscription needs to be fetched. Defaults to $USER;
 320       * @param string $order Order to sort the subscriptions.
 321       *
 322       * @return array list of subscriptions
 323       */
 324      public static function get_user_subscriptions($limitfrom = 0, $limitto = 0, $userid = 0,
 325                                                               $order = 's.courseid ASC, r.name' ) {
 326          global $DB, $USER;
 327          if ($userid == 0) {
 328              $userid = $USER->id;
 329          }
 330          $sql = self::get_subscription_join_rule_sql();
 331          $sql .= "WHERE s.userid = :userid ORDER BY $order";
 332  
 333          return self::get_instances($DB->get_records_sql($sql, array('userid' => $userid), $limitfrom, $limitto));
 334      }
 335  
 336      /**
 337       * Get count of subscriptions for a given user.
 338       *
 339       * @param int $userid Id of the user for which the subscription needs to be fetched. Defaults to $USER;
 340       *
 341       * @return int number of subscriptions
 342       */
 343      public static function count_user_subscriptions($userid = 0) {
 344          global $DB, $USER;;
 345          if ($userid == 0) {
 346              $userid = $USER->id;
 347          }
 348          $sql = self::get_subscription_join_rule_sql(true);
 349          $sql .= "WHERE s.userid = :userid";
 350  
 351          return $DB->count_records_sql($sql, array('userid' => $userid));
 352      }
 353  
 354      /**
 355       * Return a list of subscriptions for a given event.
 356       *
 357       * @param \stdClass $event the event object.
 358       *
 359       * @return array
 360       */
 361      public static function get_subscriptions_by_event(\stdClass $event) {
 362          global $DB;
 363  
 364          $sql = self::get_subscription_join_rule_sql();
 365          if ($event->contextlevel == CONTEXT_MODULE && $event->contextinstanceid != 0) {
 366              $sql .= "WHERE r.eventname = :eventname AND s.courseid = :courseid AND (s.cmid = :cmid OR s.cmid = 0)";
 367              $params = array('eventname' => $event->eventname, 'courseid' => $event->courseid, 'cmid' => $event->contextinstanceid);
 368          } else {
 369              $sql .= "WHERE r.eventname = :eventname AND (s.courseid = :courseid OR s.courseid = 0)";
 370              $params = array('eventname' => $event->eventname, 'courseid' => $event->courseid);
 371          }
 372          return self::get_instances($DB->get_records_sql($sql, $params));
 373      }
 374  
 375      /**
 376       * Return sql to join rule and subscription table.
 377       *
 378       * @param bool $count Weather if this is a count query or not.
 379       *
 380       * @return string the sql.
 381       */
 382      protected static function get_subscription_join_rule_sql($count = false) {
 383          if ($count) {
 384              $select = "SELECT COUNT(s.id) ";
 385          } else {
 386              $select = "SELECT s.*, r.description, r.descriptionformat, r.name, r.userid as ruleuserid, r.courseid as rulecourseid,
 387              r.plugin, r.eventname, r.template, r.templateformat, r.frequency, r.timewindow";
 388          }
 389          $sql = $select . "
 390                    FROM {tool_monitor_rules} r
 391                    JOIN {tool_monitor_subscriptions} s
 392                          ON r.id = s.ruleid ";
 393          return $sql;
 394      }
 395  
 396      /**
 397       * Helper method to convert db records to instances.
 398       *
 399       * @param array $arr of subscriptions.
 400       *
 401       * @return array of subscriptions as instances.
 402       */
 403      protected static function get_instances($arr) {
 404          $result = array();
 405          foreach ($arr as $key => $sub) {
 406              $result[$key] = new subscription($sub);
 407          }
 408          return $result;
 409      }
 410  
 411      /**
 412       * Get count of subscriptions for a given rule.
 413       *
 414       * @param int $ruleid rule id of the subscription.
 415       *
 416       * @return int number of subscriptions
 417       */
 418      public static function count_rule_subscriptions($ruleid) {
 419          global $DB;
 420          $sql = self::get_subscription_join_rule_sql(true);
 421          $sql .= "WHERE s.ruleid = :ruleid";
 422  
 423          return $DB->count_records_sql($sql, array('ruleid' => $ruleid));
 424      }
 425  
 426      /**
 427       * Returns true if an event in a particular course has a subscription.
 428       *
 429       * @param string $eventname the name of the event
 430       * @param int $courseid the course id
 431       * @return bool returns true if the event has subscriptions in a given course, false otherwise.
 432       */
 433      public static function event_has_subscriptions($eventname, $courseid) {
 434          global $DB;
 435  
 436          // Check if we can return these from cache.
 437          $cache = \cache::make('tool_monitor', 'eventsubscriptions');
 438  
 439          // The SQL we will be using to fill the cache if it is empty.
 440          $sql = "SELECT DISTINCT(r.eventname)
 441                    FROM {tool_monitor_subscriptions} s
 442              INNER JOIN {tool_monitor_rules} r
 443                      ON s.ruleid = r.id
 444                   WHERE s.courseid = :courseid";
 445  
 446          $sitesubscriptions = $cache->get(0);
 447          // If we do not have the site subscriptions in the cache then return them from the DB.
 448          if ($sitesubscriptions === false) {
 449              // Set the array for the cache.
 450              $sitesubscriptions = array();
 451              if ($subscriptions = $DB->get_records_sql($sql, array('courseid' => 0))) {
 452                  foreach ($subscriptions as $subscription) {
 453                      $sitesubscriptions[$subscription->eventname] = true;
 454                  }
 455              }
 456              $cache->set(0, $sitesubscriptions);
 457          }
 458  
 459          // Check if a subscription exists for this event site wide.
 460          if (isset($sitesubscriptions[$eventname])) {
 461              return true;
 462          }
 463  
 464          // If the course id is for the site, and we reached here then there is no site wide subscription for this event.
 465          if (empty($courseid)) {
 466              return false;
 467          }
 468  
 469          $coursesubscriptions = $cache->get($courseid);
 470          // If we do not have the course subscriptions in the cache then return them from the DB.
 471          if ($coursesubscriptions === false) {
 472              // Set the array for the cache.
 473              $coursesubscriptions = array();
 474              if ($subscriptions = $DB->get_records_sql($sql, array('courseid' => $courseid))) {
 475                  foreach ($subscriptions as $subscription) {
 476                      $coursesubscriptions[$subscription->eventname] = true;
 477                  }
 478              }
 479              $cache->set($courseid, $coursesubscriptions);
 480          }
 481  
 482          // Check if a subscription exists for this event in this course.
 483          if (isset($coursesubscriptions[$eventname])) {
 484              return true;
 485          }
 486  
 487          return false;
 488      }
 489  
 490      /**
 491       * Activates a group of subscriptions based on an input array of ids.
 492       *
 493       * @since 3.2.0
 494       * @param array $ids of subscription ids.
 495       * @return bool true if the operation was successful, false otherwise.
 496       */
 497      public static function activate_subscriptions(array $ids) {
 498          global $DB;
 499          if (!empty($ids)) {
 500              list($sql, $params) = $DB->get_in_or_equal($ids);
 501              $success = $DB->set_field_select('tool_monitor_subscriptions', 'inactivedate', '0', 'id ' . $sql, $params);
 502              return $success;
 503          }
 504          return false;
 505      }
 506  
 507      /**
 508       * Deactivates a group of subscriptions based on an input array of ids.
 509       *
 510       * @since 3.2.0
 511       * @param array $ids of subscription ids.
 512       * @return bool true if the operation was successful, false otherwise.
 513       */
 514      public static function deactivate_subscriptions(array $ids) {
 515          global $DB;
 516          if (!empty($ids)) {
 517              $inactivedate = time();
 518              list($sql, $params) = $DB->get_in_or_equal($ids);
 519              $success = $DB->set_field_select('tool_monitor_subscriptions', 'inactivedate', $inactivedate, 'id ' . $sql,
 520                                               $params);
 521              return $success;
 522          }
 523          return false;
 524      }
 525  
 526      /**
 527       * Deletes subscriptions which have been inactive for a period of time.
 528       *
 529       * @since 3.2.0
 530       * @param int $userid if provided, only this user's stale subscriptions will be deleted.
 531       * @return bool true if the operation was successful, false otherwise.
 532       */
 533      public static function delete_stale_subscriptions($userid = 0) {
 534          global $DB;
 535          // Get the expiry duration, in days.
 536          $cutofftime = strtotime("-" . self::INACTIVE_SUBSCRIPTION_LIFESPAN_IN_DAYS . " days", time());
 537  
 538          if (!empty($userid)) {
 539              // Remove any stale subscriptions for the desired user only.
 540              $success = $DB->delete_records_select('tool_monitor_subscriptions',
 541                                                    'userid = ? AND inactivedate < ? AND inactivedate <> 0',
 542                                                    array($userid, $cutofftime));
 543  
 544          } else {
 545              // Remove all stale subscriptions.
 546              $success = $DB->delete_records_select('tool_monitor_subscriptions',
 547                                                    'inactivedate < ? AND inactivedate <> 0',
 548                                                    array($cutofftime));
 549          }
 550          return $success;
 551      }
 552  
 553      /**
 554       * Check whether a subscription is active.
 555       *
 556       * @since 3.2.0
 557       * @param \tool_monitor\subscription $subscription instance.
 558       * @return bool true if the subscription is active, false otherwise.
 559       */
 560      public static function subscription_is_active(subscription $subscription) {
 561          return empty($subscription->inactivedate);
 562      }
 563  }