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Differences Between: [Versions 310 and 402] [Versions 311 and 402] [Versions 39 and 402]

   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   * Exported post builder class.
  19   *
  20   * @package    mod_forum
  21   * @copyright  2019 Ryan Wyllie <ryan@moodle.com>
  22   * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
  23   */
  24  
  25  namespace mod_forum\local\builders;
  26  
  27  defined('MOODLE_INTERNAL') || die();
  28  
  29  use mod_forum\local\entities\discussion as discussion_entity;
  30  use mod_forum\local\entities\forum as forum_entity;
  31  use mod_forum\local\entities\post as post_entity;
  32  use mod_forum\local\factories\legacy_data_mapper as legacy_data_mapper_factory;
  33  use mod_forum\local\factories\exporter as exporter_factory;
  34  use mod_forum\local\factories\vault as vault_factory;
  35  use mod_forum\local\factories\manager as manager_factory;
  36  use core_tag_tag;
  37  use moodle_exception;
  38  use renderer_base;
  39  use stdClass;
  40  
  41  /**
  42   * Exported post builder class.
  43   *
  44   * This class is an implementation of the builder pattern (loosely). It is responsible
  45   * for taking a set of related forums, discussions, and posts and generate the exported
  46   * version of the posts.
  47   *
  48   * It encapsulates the complexity involved with exporting posts. All of the relevant
  49   * additional resources will be loaded by this class in order to ensure the exporting
  50   * process can happen.
  51   *
  52   * See this doc for more information on the builder pattern:
  53   * https://designpatternsphp.readthedocs.io/en/latest/Creational/Builder/README.html
  54   *
  55   * @copyright  2019 Ryan Wyllie <ryan@moodle.com>
  56   * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
  57   */
  58  class exported_posts {
  59      /** @var renderer_base $renderer Core renderer */
  60      private $renderer;
  61  
  62      /** @var legacy_data_mapper_factory $legacydatamapperfactory Data mapper factory */
  63      private $legacydatamapperfactory;
  64  
  65      /** @var exporter_factory $exporterfactory Exporter factory */
  66      private $exporterfactory;
  67  
  68      /** @var vault_factory $vaultfactory Vault factory */
  69      private $vaultfactory;
  70  
  71      /** @var rating_manager $ratingmanager Rating manager */
  72      private $ratingmanager;
  73  
  74      /** @var manager_factory $managerfactory Manager factory */
  75      private $managerfactory;
  76  
  77      /**
  78       * Constructor.
  79       *
  80       * @param renderer_base $renderer Core renderer
  81       * @param legacy_data_mapper_factory $legacydatamapperfactory Legacy data mapper factory
  82       * @param exporter_factory $exporterfactory Exporter factory
  83       * @param vault_factory $vaultfactory Vault factory
  84       * @param manager_factory $managerfactory Manager factory
  85       */
  86      public function __construct(
  87          renderer_base $renderer,
  88          legacy_data_mapper_factory $legacydatamapperfactory,
  89          exporter_factory $exporterfactory,
  90          vault_factory $vaultfactory,
  91          manager_factory $managerfactory
  92      ) {
  93          $this->renderer = $renderer;
  94          $this->legacydatamapperfactory = $legacydatamapperfactory;
  95          $this->exporterfactory = $exporterfactory;
  96          $this->vaultfactory = $vaultfactory;
  97          $this->managerfactory = $managerfactory;
  98          $this->ratingmanager = $managerfactory->get_rating_manager();
  99      }
 100  
 101      /**
 102       * Build the exported posts for a given set of forums, discussions, and posts.
 103       *
 104       * This will typically be used for a list of posts in the same discussion/forum however
 105       * it does support exporting any arbitrary list of posts as long as the caller also provides
 106       * a unique list of all discussions for the list of posts and all forums for the list of discussions.
 107       *
 108       * Increasing the number of different forums being processed will increase the processing time
 109       * due to processing multiple contexts (for things like capabilities, files, etc). The code attempts
 110       * to load the additional resources as efficiently as possible but there is no way around some of
 111       * the additional overhead.
 112       *
 113       * Note: Some posts will be removed as part of the build process according to capabilities.
 114       * A one-to-one mapping should not be expected.
 115       *
 116       * @param stdClass $user The user to export the posts for.
 117       * @param forum_entity[] $forums A list of all forums that each of the $discussions belong to
 118       * @param discussion_entity[] $discussions A list of all discussions that each of the $posts belong to
 119       * @param post_entity[] $posts The list of posts to export.
 120       * @param bool $includeinlineattachments Whether inline attachments should be included or not.
 121       * @return stdClass[] List of exported posts in the same order as the $posts array.
 122       */
 123      public function build(
 124          stdClass $user,
 125          array $forums,
 126          array $discussions,
 127          array $posts,
 128          bool $includeinlineattachments = false
 129      ) : array {
 130          // Format the forums and discussion to make them more easily accessed later.
 131          $forums = array_reduce($forums, function($carry, $forum) {
 132              $carry[$forum->get_id()] = $forum;
 133              return $carry;
 134          }, []);
 135          $discussions = array_reduce($discussions, function($carry, $discussion) {
 136              $carry[$discussion->get_id()] = $discussion;
 137              return $carry;
 138          }, []);
 139  
 140          // Group the posts by discussion and forum so that we can load the resources in
 141          // batches to improve performance.
 142          $groupedposts = $this->group_posts_by_discussion($forums, $discussions, $posts);
 143          // Load all of the resources we need in order to export the posts.
 144          $authorsbyid = $this->get_authors_for_posts($posts);
 145          $authorcontextids = $this->get_author_context_ids(array_keys($authorsbyid));
 146          $attachmentsbypostid = $this->get_attachments_for_posts($groupedposts);
 147          $inlineattachments = [];
 148          if ($includeinlineattachments) {
 149              $inlineattachments = $this->get_inline_attachments_for_posts($groupedposts);
 150          }
 151          $groupsbycourseandauthorid = $this->get_author_groups_from_posts($groupedposts);
 152          $tagsbypostid = $this->get_tags_from_posts($posts);
 153          $ratingbypostid = $this->get_ratings_from_posts($user, $groupedposts);
 154          $readreceiptcollectionbyforumid = $this->get_read_receipts_from_posts($user, $groupedposts);
 155          $exportedposts = [];
 156  
 157          // Export each set of posts per discussion because it's the largest chunks we can
 158          // break them into due to constraints on capability checks.
 159          foreach ($groupedposts as $grouping) {
 160              [
 161                  'forum' => $forum,
 162                  'discussion' => $discussion,
 163                  'posts' => $groupedposts
 164              ] = $grouping;
 165  
 166              // Exclude posts the user cannot see, such as certain posts in Q and A forums.
 167              $capabilitymanager = $this->managerfactory->get_capability_manager($forum);
 168              $groupedposts = array_filter($groupedposts, function($post) use ($capabilitymanager, $user, $discussion) {
 169                  return $capabilitymanager->can_view_post($user, $discussion, $post);
 170              });
 171  
 172              $forumid = $forum->get_id();
 173              $courseid = $forum->get_course_record()->id;
 174              $postsexporter = $this->exporterfactory->get_posts_exporter(
 175                  $user,
 176                  $forum,
 177                  $discussion,
 178                  $groupedposts,
 179                  $authorsbyid,
 180                  $authorcontextids,
 181                  $attachmentsbypostid,
 182                  $groupsbycourseandauthorid[$courseid],
 183                  $readreceiptcollectionbyforumid[$forumid] ?? null,
 184                  $tagsbypostid,
 185                  $ratingbypostid,
 186                  true,
 187                  $inlineattachments
 188              );
 189              ['posts' => $exportedgroupedposts] = (array) $postsexporter->export($this->renderer);
 190              $exportedposts = array_merge($exportedposts, $exportedgroupedposts);
 191          }
 192  
 193          if (count($forums) == 1 && count($discussions) == 1) {
 194              // All of the posts belong to a single discussion in a single forum so
 195              // the exported order will match the given $posts array.
 196              return $exportedposts;
 197          } else {
 198              // Since we grouped the posts by discussion and forum the ordering of the
 199              // exported posts may be different to the given $posts array so we should
 200              // sort it back into the correct order for the caller.
 201              return $this->sort_exported_posts($posts, $exportedposts);
 202          }
 203      }
 204  
 205      /**
 206       * Group the posts by which discussion they belong to in order for them to be processed
 207       * in chunks by the exporting.
 208       *
 209       * Returns a list of groups where each group has a forum, discussion, and list of posts.
 210       * E.g.
 211       * [
 212       *      [
 213       *          'forum' => <forum_entity>,
 214       *          'discussion' => <discussion_entity>,
 215       *          'posts' => [
 216       *              <post_entity in discussion>,
 217       *              <post_entity in discussion>,
 218       *              <post_entity in discussion>
 219       *          ]
 220       *      ]
 221       * ]
 222       *
 223       * @param forum_entity[] $forums A list of all forums that each of the $discussions belong to, indexed by id.
 224       * @param discussion_entity[] $discussions A list of all discussions that each of the $posts belong to, indexed by id.
 225       * @param post_entity[] $posts The list of posts to process.
 226       * @return array List of grouped posts. Each group has a discussion, forum, and posts.
 227       */
 228      private function group_posts_by_discussion(array $forums, array $discussions, array $posts) : array {
 229          return array_reduce($posts, function($carry, $post) use ($forums, $discussions) {
 230              $discussionid = $post->get_discussion_id();
 231              if (!isset($discussions[$discussionid])) {
 232                  throw new moodle_exception('Unable to find discussion with id ' . $discussionid);
 233              }
 234  
 235              if (isset($carry[$discussionid])) {
 236                  $carry[$discussionid]['posts'][] = $post;
 237              } else {
 238                  $discussion = $discussions[$discussionid];
 239                  $forumid = $discussion->get_forum_id();
 240  
 241                  if (!isset($forums[$forumid])) {
 242                      throw new moodle_exception('Unable to find forum with id ' . $forumid);
 243                  }
 244  
 245                  $carry[$discussionid] = [
 246                      'forum' => $forums[$forumid],
 247                      'discussion' => $discussions[$discussionid],
 248                      'posts' => [$post]
 249                  ];
 250              }
 251  
 252              return $carry;
 253          }, []);
 254      }
 255  
 256      /**
 257       * Load the list of authors for the given posts.
 258       *
 259       * The list of authors will be indexed by the author id.
 260       *
 261       * @param post_entity[] $posts The list of posts to process.
 262       * @return author_entity[]
 263       */
 264      private function get_authors_for_posts(array $posts) : array {
 265          $authorvault = $this->vaultfactory->get_author_vault();
 266          return $authorvault->get_authors_for_posts($posts);
 267      }
 268  
 269      /**
 270       * Get the user context ids for each of the authors.
 271       *
 272       * @param int[] $authorids The list of author ids to fetch context ids for.
 273       * @return int[] Context ids indexed by author id
 274       */
 275      private function get_author_context_ids(array $authorids) : array {
 276          $authorvault = $this->vaultfactory->get_author_vault();
 277          return $authorvault->get_context_ids_for_author_ids($authorids);
 278      }
 279  
 280      /**
 281       * Load the list of all inline attachments for the posts. The list of attachments will be
 282       * indexed by the post id.
 283       *
 284       * @param array $groupedposts List of posts grouped by discussions.
 285       * @return stored_file[]
 286       */
 287      private function get_inline_attachments_for_posts(array $groupedposts) : array {
 288          $inlineattachmentsbypostid = [];
 289          $postattachmentvault = $this->vaultfactory->get_post_attachment_vault();
 290          $postsbyforum = array_reduce($groupedposts, function($carry, $grouping) {
 291              ['forum' => $forum, 'posts' => $posts] = $grouping;
 292  
 293              $forumid = $forum->get_id();
 294              if (!isset($carry[$forumid])) {
 295                  $carry[$forumid] = [
 296                      'forum' => $forum,
 297                      'posts' => []
 298                  ];
 299              }
 300  
 301              $carry[$forumid]['posts'] = array_merge($carry[$forumid]['posts'], $posts);
 302              return $carry;
 303          }, []);
 304  
 305          foreach ($postsbyforum as $grouping) {
 306              ['forum' => $forum, 'posts' => $posts] = $grouping;
 307              $inlineattachments = $postattachmentvault->get_inline_attachments_for_posts($forum->get_context(), $posts);
 308  
 309              // Have to loop in order to maintain the correct indexes since they are numeric.
 310              foreach ($inlineattachments as $postid => $attachment) {
 311                  $inlineattachmentsbypostid[$postid] = $attachment;
 312              }
 313          }
 314  
 315          return $inlineattachmentsbypostid;
 316      }
 317  
 318      /**
 319       * Load the list of all attachments for the posts. The list of attachments will be
 320       * indexed by the post id.
 321       *
 322       * @param array $groupedposts List of posts grouped by discussions.
 323       * @return stored_file[]
 324       */
 325      private function get_attachments_for_posts(array $groupedposts) : array {
 326          $attachmentsbypostid = [];
 327          $postattachmentvault = $this->vaultfactory->get_post_attachment_vault();
 328          $postsbyforum = array_reduce($groupedposts, function($carry, $grouping) {
 329              ['forum' => $forum, 'posts' => $posts] = $grouping;
 330  
 331              $forumid = $forum->get_id();
 332              if (!isset($carry[$forumid])) {
 333                  $carry[$forumid] = [
 334                      'forum' => $forum,
 335                      'posts' => []
 336                  ];
 337              }
 338  
 339              $carry[$forumid]['posts'] = array_merge($carry[$forumid]['posts'], $posts);
 340              return $carry;
 341          }, []);
 342  
 343          foreach ($postsbyforum as $grouping) {
 344              ['forum' => $forum, 'posts' => $posts] = $grouping;
 345              $attachments = $postattachmentvault->get_attachments_for_posts($forum->get_context(), $posts);
 346  
 347              // Have to loop in order to maintain the correct indexes since they are numeric.
 348              foreach ($attachments as $postid => $attachment) {
 349                  $attachmentsbypostid[$postid] = $attachment;
 350              }
 351          }
 352  
 353          return $attachmentsbypostid;
 354      }
 355  
 356      /**
 357       * Get the groups for each author of the given posts.
 358       *
 359       * The results are grouped by course and then author id because the groups are
 360       * contextually related to the course, e.g. a single author can be part of two different
 361       * sets of groups in two different courses.
 362       *
 363       * @param array $groupedposts List of posts grouped by discussions.
 364       * @return array List of groups indexed by forum id and then author id.
 365       */
 366      private function get_author_groups_from_posts(array $groupedposts) : array {
 367          $groupsbyauthorid = [];
 368          $authoridsbycourseid = [];
 369  
 370          // Get the unique list of author ids for each course in the grouped
 371          // posts. Grouping by course is the largest grouping we can achieve.
 372          foreach ($groupedposts as $grouping) {
 373              ['forum' => $forum, 'posts' => $posts] = $grouping;
 374              $course = $forum->get_course_record();
 375              $courseid = $course->id;
 376  
 377              if (!isset($authoridsbycourseid[$courseid])) {
 378                  $coursemodule = $forum->get_course_module_record();
 379                  $authoridsbycourseid[$courseid] = [
 380                      'groupingid' => $coursemodule->groupingid,
 381                      'authorids' => []
 382                  ];
 383              }
 384  
 385              $authorids = array_map(function($post) {
 386                  return $post->get_author_id();
 387              }, $posts);
 388  
 389              foreach ($authorids as $authorid) {
 390                  $authoridsbycourseid[$courseid]['authorids'][$authorid] = $authorid;
 391              }
 392          }
 393  
 394          // Load each set of groups per course.
 395          foreach ($authoridsbycourseid as $courseid => $values) {
 396              ['groupingid' => $groupingid, 'authorids' => $authorids] = $values;
 397              $authorgroups = groups_get_all_groups(
 398                  $courseid,
 399                  array_keys($authorids),
 400                  $groupingid,
 401                  'g.*, gm.id, gm.groupid, gm.userid'
 402              );
 403  
 404              if (!isset($groupsbyauthorid[$courseid])) {
 405                  $groupsbyauthorid[$courseid] = [];
 406              }
 407  
 408              foreach ($authorgroups as $group) {
 409                  // Clean up data returned from groups_get_all_groups.
 410                  $userid = $group->userid;
 411                  $groupid = $group->groupid;
 412  
 413                  unset($group->userid);
 414                  unset($group->groupid);
 415                  $group->id = $groupid;
 416  
 417                  if (!isset($groupsbyauthorid[$courseid][$userid])) {
 418                      $groupsbyauthorid[$courseid][$userid] = [];
 419                  }
 420  
 421                  $groupsbyauthorid[$courseid][$userid][] = $group;
 422              }
 423          }
 424  
 425          return $groupsbyauthorid;
 426      }
 427  
 428      /**
 429       * Get the list of tags for each of the posts. The tags will be returned in an
 430       * array indexed by the post id.
 431       *
 432       * @param post_entity[] $posts The list of posts to load tags for.
 433       * @return array Sets of tags indexed by post id.
 434       */
 435      private function get_tags_from_posts(array $posts) : array {
 436          $postids = array_map(function($post) {
 437              return $post->get_id();
 438          }, $posts);
 439          return core_tag_tag::get_items_tags('mod_forum', 'forum_posts', $postids);
 440      }
 441  
 442      /**
 443       * Get the list of ratings for each post. The ratings are returned in an array
 444       * indexed by the post id.
 445       *
 446       * @param stdClass $user The user viewing the ratings.
 447       * @param array $groupedposts List of posts grouped by discussions.
 448       * @return array Sets of ratings indexed by post id.
 449       */
 450      private function get_ratings_from_posts(stdClass $user, array $groupedposts) {
 451          $ratingsbypostid = [];
 452          $postsdatamapper = $this->legacydatamapperfactory->get_post_data_mapper();
 453          $postsbyforum = array_reduce($groupedposts, function($carry, $grouping) {
 454              ['forum' => $forum, 'posts' => $posts] = $grouping;
 455  
 456              $forumid = $forum->get_id();
 457              if (!isset($carry[$forumid])) {
 458                  $carry[$forumid] = [
 459                      'forum' => $forum,
 460                      'posts' => []
 461                  ];
 462              }
 463  
 464              $carry[$forumid]['posts'] = array_merge($carry[$forumid]['posts'], $posts);
 465              return $carry;
 466          }, []);
 467  
 468          foreach ($postsbyforum as $grouping) {
 469              ['forum' => $forum, 'posts' => $posts] = $grouping;
 470  
 471              if (!$forum->has_rating_aggregate()) {
 472                  continue;
 473              }
 474  
 475              $items = $postsdatamapper->to_legacy_objects($posts);
 476              $ratingoptions = (object) [
 477                  'context' => $forum->get_context(),
 478                  'component' => 'mod_forum',
 479                  'ratingarea' => 'post',
 480                  'items' => $items,
 481                  'aggregate' => $forum->get_rating_aggregate(),
 482                  'scaleid' => $forum->get_scale(),
 483                  'userid' => $user->id,
 484                  'assesstimestart' => $forum->get_assess_time_start(),
 485                  'assesstimefinish' => $forum->get_assess_time_finish()
 486              ];
 487  
 488              $rm = $this->ratingmanager;
 489              $items = $rm->get_ratings($ratingoptions);
 490  
 491              foreach ($items as $item) {
 492                  $ratingsbypostid[$item->id] = empty($item->rating) ? null : $item->rating;
 493              }
 494          }
 495  
 496          return $ratingsbypostid;
 497      }
 498  
 499      /**
 500       * Get the read receipt collections for the given viewing user and each forum. The
 501       * receipt collections will only be loaded for posts in forums that the user is tracking.
 502       *
 503       * The receipt collections are returned in an array indexed by the forum ids.
 504       *
 505       * @param stdClass $user The user viewing the posts.
 506       * @param array $groupedposts List of posts grouped by discussions.
 507       */
 508      private function get_read_receipts_from_posts(stdClass $user, array $groupedposts) {
 509          $forumdatamapper = $this->legacydatamapperfactory->get_forum_data_mapper();
 510          $trackedforums = [];
 511          $trackedpostids = [];
 512  
 513          foreach ($groupedposts as $group) {
 514              ['forum' => $forum, 'posts' => $posts] = $group;
 515              $forumid = $forum->get_id();
 516  
 517              if (!isset($trackedforums[$forumid])) {
 518                  $forumrecord = $forumdatamapper->to_legacy_object($forum);
 519                  $trackedforums[$forumid] = forum_tp_is_tracked($forumrecord, $user);
 520              }
 521  
 522              if ($trackedforums[$forumid]) {
 523                  foreach ($posts as $post) {
 524                      $trackedpostids[] = $post->get_id();
 525                  }
 526              }
 527          }
 528  
 529          if (empty($trackedpostids)) {
 530              return [];
 531          }
 532  
 533          // We can just load a single receipt collection for all tracked posts.
 534          $receiptvault = $this->vaultfactory->get_post_read_receipt_collection_vault();
 535          $readreceiptcollection = $receiptvault->get_from_user_id_and_post_ids($user->id, $trackedpostids);
 536          $receiptsbyforumid = [];
 537  
 538          // Assign the collection to all forums that are tracked.
 539          foreach ($trackedforums as $forumid => $tracked) {
 540              if ($tracked) {
 541                  $receiptsbyforumid[$forumid] = $readreceiptcollection;
 542              }
 543          }
 544  
 545          return $receiptsbyforumid;
 546      }
 547  
 548      /**
 549       * Sort the list of exported posts back into the same order as the given posts.
 550       * The ordering of the exported posts can often deviate from the given posts due
 551       * to the process of exporting them so we need to sort them back into the order
 552       * that the calling code expected.
 553       *
 554       * @param post_entity[] $posts The posts in the expected order.
 555       * @param stdClass[] $exportedposts The list of exported posts in any order.
 556       * @return stdClass[] Sorted exported posts.
 557       */
 558      private function sort_exported_posts(array $posts, array $exportedposts) {
 559          $postindexes = [];
 560          foreach (array_values($posts) as $index => $post) {
 561              $postindexes[$post->get_id()] = $index;
 562          }
 563  
 564          $sortedexportedposts = [];
 565  
 566          foreach ($exportedposts as $exportedpost) {
 567              $index = $postindexes[$exportedpost->id];
 568              $sortedexportedposts[$index] = $exportedpost;
 569          }
 570  
 571          return $sortedexportedposts;
 572      }
 573  }