[Summary view]

   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  namespace mod_assign;
  18  
  19  use assign;
  20  use core_php_time_limit;
  21  use mod_assign\event\all_submissions_downloaded;
  22  use core\session\manager as sessionmanager;
  23  use core_files\archive_writer;
  24  use stdClass;
  25  use assign_plugin;
  26  use stored_file;
  27  
  28  /**
  29   * Class to download user submissions.
  30   *
  31   * @package    mod_assign
  32   * @copyright  2022 Ferran Recio <ferran@moodle.com>
  33   * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
  34   */
  35  class downloader {
  36      /** @var assign the module manager instance. */
  37      private $manager;
  38  
  39      /** @var stdClass the assign instance record. */
  40      private $instance;
  41  
  42      /** @var array|null the selected user ids, if any. */
  43      private $userids = null;
  44  
  45      /** @var int $groupmode the activity group mode. */
  46      private $groupmode = '';
  47  
  48      /** @var int $groupid the exported groupid. */
  49      private $groupid = 0;
  50  
  51      /** @var array $filesforzipping the files to zipo (path => file) */
  52      protected $filesforzipping;
  53  
  54      /** @var array $prefixes all loaded the student prefixes.
  55       *
  56       * A prefix will be converted into a file prefix or a folder name (depends on downloadasfolders).
  57       */
  58      private $prefixes;
  59  
  60      /** @var int $downloadasfolders the files to zipo (path => file) */
  61      private $downloadasfolders;
  62  
  63      /**
  64       * Class constructor.
  65       *
  66       * @param assign $manager the instance manager
  67       * @param array|null $userids the user ids to download.
  68       */
  69      public function __construct(assign $manager, ?array $userids = null) {
  70          $this->manager = $manager;
  71          $this->userids = $userids;
  72          $this->instance = $manager->get_instance();
  73  
  74          $this->downloadasfolders = get_user_preferences('assign_downloadasfolders', 1);
  75  
  76          $cm = $manager->get_course_module();
  77          $this->groupmode = groups_get_activity_groupmode($cm);
  78          if ($this->groupmode) {
  79              $this->groupid = groups_get_activity_group($cm, true);
  80          }
  81      }
  82  
  83      /**
  84       * Load the filelist.
  85       *
  86       * @return bool true if there are some files to zip.
  87       */
  88      public function load_filelist(): bool {
  89          $manager = $this->manager;
  90          $groupid = $this->groupid;
  91  
  92          // Increase the server timeout to handle the creation and sending of large zip files.
  93          core_php_time_limit::raise();
  94  
  95          $manager->require_view_grades();
  96  
  97          // Load all users with submit.
  98          $students = get_enrolled_users(
  99              $manager->get_context(),
 100              "mod/assign:submit",
 101              0,
 102              'u.*',
 103              null,
 104              0,
 105              0,
 106              $manager->show_only_active_users()
 107          );
 108  
 109          // Build a list of files to zip.
 110          $this->filesforzipping = [];
 111  
 112          // Get all the files for each student.
 113          foreach ($students as $student) {
 114              // Download all assigments submission or only selected users.
 115              if ($this->userids && !in_array($student->id, $this->userids)) {
 116                  continue;
 117              }
 118              if (!groups_is_member($groupid, $student->id) && $this->groupmode && $groupid) {
 119                  continue;
 120              }
 121              $this->load_student_filelist($student);
 122          }
 123          return !empty($this->filesforzipping);
 124      }
 125  
 126      /**
 127       * Load an individual student filelist.
 128       *
 129       * @param stdClass $student the user record
 130       */
 131      private function load_student_filelist(stdClass $student) {
 132          $submission = $this->get_student_submission($student);
 133          if (!$submission) {
 134              return;
 135          }
 136          $prefix = $this->get_student_prefix($student);
 137          if (isset($this->prefixes[$prefix])) {
 138              // We already send that file (in group mode).
 139              return;
 140          }
 141          $this->prefixes[$prefix] = $student->id;
 142  
 143          foreach ($this->manager->get_submission_plugins() as $plugin) {
 144              if (!$plugin->is_enabled() || !$plugin->is_visible()) {
 145                  continue;
 146              }
 147              $this->load_submissionplugin_filelist($student, $plugin, $submission, $prefix);
 148          }
 149      }
 150  
 151      /**
 152       * Return the student submission if any.
 153       *
 154       * @param stdClass $student the user record
 155       * @return stdClass|null the user submission or null if none
 156       */
 157      private function get_student_submission(stdClass $student): ?stdClass {
 158          if ($this->instance->teamsubmission) {
 159              $submission = $this->manager->get_group_submission($student->id, 0, false);
 160          } else {
 161              $submission = $this->manager->get_user_submission($student->id, false);
 162          }
 163          return $submission ?: null;
 164      }
 165  
 166      /**
 167       * Return the file prefix used to generate the each submission folder or file.
 168       *
 169       * @param stdClass $student the user record
 170       * @return string the submission prefix
 171       */
 172      private function get_student_prefix(stdClass $student): string {
 173          $manager = $this->manager;
 174  
 175          // Team submissions are by group, not by student.
 176          if ($this->instance->teamsubmission) {
 177              $submissiongroup = $manager->get_submission_group($student->id);
 178              if ($submissiongroup) {
 179                  $groupname = format_string($submissiongroup->name, true, ['context' => $manager->get_context()]);
 180                  $groupinfo = '_' . $submissiongroup->id;
 181              } else {
 182                  $groupname = get_string('defaultteam', 'mod_assign');
 183                  $groupinfo = '';
 184              }
 185              $prefix = str_replace('_', ' ', $groupname);
 186              return clean_filename($prefix . $groupinfo);
 187          }
 188          // Individual submissions are by user.
 189          if ($manager->is_blind_marking()) {
 190              $fullname = get_string('participant', 'mod_assign');
 191          } else {
 192              $fullname = fullname($student, has_capability('moodle/site:viewfullnames', $manager->get_context()));
 193          }
 194          $prefix = str_replace('_', ' ', $fullname);
 195          $prefix = clean_filename($prefix . '_' . $manager->get_uniqueid_for_user($student->id));
 196          return $prefix;
 197      }
 198  
 199      /**
 200       * Load a submission plugin filelist for a specific user.
 201       *
 202       * @param stdClass $student the user record
 203       * @param assign_plugin $plugin the submission plugin instance
 204       * @param stdClass $submission the submission object
 205       * @param string $prefix the files prefix
 206       */
 207      private function load_submissionplugin_filelist(
 208          stdClass $student,
 209          assign_plugin $plugin,
 210          stdClass $submission,
 211          string $prefix
 212      ) {
 213          $subtype = $plugin->get_subtype();
 214          $type = $plugin->get_type();
 215  
 216          if ($this->downloadasfolders) {
 217              // Create a folder for each user for each assignment plugin.
 218              // This is the default behavior for version of Moodle >= 3.1.
 219              $submission->exportfullpath = true;
 220              $pluginfiles = $plugin->get_files($submission, $student);
 221              foreach ($pluginfiles as $zipfilepath => $file) {
 222                  $zipfilename = basename($zipfilepath);
 223                  $prefixedfilename = clean_filename($prefix . '_' . $subtype . '_' . $type);
 224                  if ($type == 'file') {
 225                      $pathfilename = $prefixedfilename . $file->get_filepath() . $zipfilename;
 226                  } else {
 227                      $pathfilename = $prefixedfilename . '/' . $zipfilename;
 228                  }
 229                  $pathfilename = clean_param($pathfilename, PARAM_PATH);
 230                  $this->filesforzipping[$pathfilename] = $file;
 231              }
 232          } else {
 233              // Create a single folder for all users of all assignment plugins.
 234              // This was the default behavior for version of Moodle < 3.1.
 235              $submission->exportfullpath = false;
 236              $pluginfiles = $plugin->get_files($submission, $student);
 237              foreach ($pluginfiles as $zipfilename => $file) {
 238                  $prefixedfilename = clean_filename($prefix . '_' . $subtype . '_' . $type . '_' . $zipfilename);
 239                  $this->filesforzipping[$prefixedfilename] = $file;
 240              }
 241          }
 242      }
 243  
 244      /**
 245       * Download the exported zip.
 246       *
 247       * This method will terminate the current script when the file is send.
 248       */
 249      public function download_zip() {
 250          $filename = $this->get_zip_filename();
 251          all_submissions_downloaded::create_from_assign($this->manager)->trigger();
 252          sessionmanager::write_close();
 253          $zipwriter = archive_writer::get_stream_writer($filename, archive_writer::ZIP_WRITER);
 254  
 255          // Stream the files into the zip.
 256          foreach ($this->filesforzipping as $pathinzip => $file) {
 257              if ($file instanceof stored_file) {
 258                  // Most of cases are stored_file.
 259                  $zipwriter->add_file_from_stored_file($pathinzip, $file);
 260              } else if (is_array($file)) {
 261                  // Save $file as contents, from onlinetext subplugin.
 262                  $content = reset($file);
 263                  $zipwriter->add_file_from_string($pathinzip, $content);
 264              }
 265          }
 266          // Finish the archive.
 267          $zipwriter->finish();
 268          exit();
 269      }
 270  
 271      /**
 272       * Generate the zip filename.
 273       *
 274       * @return string the zip filename
 275       */
 276      private function get_zip_filename(): string {
 277          $manager = $this->manager;
 278          $filenameparts = [
 279              $manager->get_course()->shortname,
 280              $this->instance->name,
 281          ];
 282          if (!empty($this->groupid)) {
 283              $filenameparts[] = format_string(groups_get_group_name($this->groupid), true, ['context' => $manager->get_context()]);
 284          }
 285          $filenameparts[] = $manager->get_course_module()->id;
 286  
 287          return clean_filename(implode('-', $filenameparts). '.zip');
 288      }
 289  }