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Differences Between: [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   * Any access indicator.
  19   *
  20   * @package   core
  21   * @copyright 2019 David Monllao {@link http://www.davidmonllao.com}
  22   * @license   http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
  23   */
  24  
  25  namespace core\analytics\indicator;
  26  
  27  defined('MOODLE_INTERNAL') || die();
  28  
  29  /**
  30   * Any access indicator.
  31   *
  32   * @package   core
  33   * @copyright 2019 David Monllao {@link http://www.davidmonllao.com}
  34   * @license   http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
  35   */
  36  class any_course_access extends \core_analytics\local\indicator\binary {
  37  
  38      /**
  39       * Returns the name.
  40       *
  41       * If there is a corresponding '_help' string this will be shown as well.
  42       *
  43       * @return \lang_string
  44       */
  45      public static function get_name() : \lang_string {
  46          return new \lang_string('indicator:anycourseaccess');
  47      }
  48  
  49      /**
  50       * required_sample_data
  51       *
  52       * @return string[]
  53       */
  54      public static function required_sample_data() {
  55          return array('course', 'user');
  56      }
  57  
  58      /**
  59       * Store userid => timeaccess relation if the provided analysable is a course.
  60       *
  61       * @param  \core_analytics\analysable $analysable
  62       * @return null
  63       */
  64      public function fill_per_analysable_caches(\core_analytics\analysable $analysable) {
  65          global $DB;
  66  
  67          if ($analysable instanceof \core_analytics\course) {
  68              // Indexed by userid (there is a UNIQUE KEY at DB level).
  69              $this->lastaccesses = $DB->get_records('user_lastaccess', ['courseid' => $analysable->get_id()],
  70                  '', 'userid, timeaccess');
  71          }
  72      }
  73  
  74      /**
  75       * calculate_sample
  76       *
  77       * @param int $sampleid
  78       * @param string $sampleorigin
  79       * @param int $starttime
  80       * @param int $endtime
  81       * @return float
  82       */
  83      protected function calculate_sample($sampleid, $sampleorigin, $starttime = false, $endtime = false) {
  84  
  85          $course = $this->retrieve('course', $sampleid);
  86          $user = $this->retrieve('user', $sampleid);
  87  
  88          // We first try using user_lastaccess as it is much faster than the log table.
  89          if (empty($this->lastaccesses[$user->id]->timeaccess)) {
  90              // The user never accessed.
  91              return self::get_min_value();
  92          } else if (!$starttime && !$endtime) {
  93              // No time restrictions, so all good as long as there is a record.
  94              return self::get_max_value();
  95          } else if ($starttime && $this->lastaccesses[$user->id]->timeaccess < $starttime) {
  96              // The last access is prior to $starttime.
  97              return self::get_min_value();
  98          } else if ($endtime && $this->lastaccesses[$user->id]->timeaccess < $endtime) {
  99              // The last access is before the $endtime.
 100              return self::get_max_value();
 101          } else if ($starttime && !$endtime && $starttime <= $this->lastaccesses[$user->id]->timeaccess) {
 102              // No end time, so max value as long as the last access is after $starttime.
 103              return self::get_max_value();
 104          }
 105  
 106          // If the last access is after $endtime we can not know for sure if the user accessed or not
 107          // between $starttime and $endtime, we need to check the logs table in this case. Note that
 108          // it is unlikely that we will reach this point as this indicator will be used in models whose
 109          // dates are in the past.
 110  
 111          if (!$logstore = \core_analytics\manager::get_analytics_logstore()) {
 112              throw new \coding_exception('No available log stores');
 113          }
 114  
 115          // Filter by context to use the logstore_standard_log db table index.
 116          $select = "userid = :userid AND courseid = :courseid";
 117          $params = ['courseid' => $course->id, 'userid' => $user->id];
 118  
 119          if ($starttime) {
 120              $select .= " AND timecreated > :starttime";
 121              $params['starttime'] = $starttime;
 122          }
 123          if ($endtime) {
 124              $select .= " AND timecreated <= :endtime";
 125              $params['endtime'] = $endtime;
 126          }
 127  
 128          $nlogs = $logstore->get_events_select_count($select, $params);
 129          if ($nlogs) {
 130              return self::get_max_value();
 131          } else {
 132              return self::get_min_value();
 133          }
 134      }
 135  }