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Differences Between: [Versions 310 and 311] [Versions 311 and 400] [Versions 311 and 401] [Versions 311 and 402] [Versions 311 and 403] [Versions 39 and 311]

   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   * Content bank class
  19   *
  20   * @package    core_contentbank
  21   * @copyright  2020 Amaia Anabitarte <amaia@moodle.com>
  22   * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
  23   */
  24  
  25  namespace core_contentbank;
  26  
  27  use core_plugin_manager;
  28  use stored_file;
  29  use context;
  30  
  31  /**
  32   * Content bank class
  33   *
  34   * @package    core_contentbank
  35   * @copyright  2020 Amaia Anabitarte <amaia@moodle.com>
  36   * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
  37   */
  38  class contentbank {
  39  
  40      /** @var array All the context levels allowed in the content bank */
  41      private const ALLOWED_CONTEXT_LEVELS = [CONTEXT_SYSTEM, CONTEXT_COURSECAT, CONTEXT_COURSE];
  42  
  43      /** @var array Enabled content types. */
  44      private $enabledcontenttypes = null;
  45  
  46      /**
  47       * Obtains the list of core_contentbank_content objects currently active.
  48       *
  49       * The list does not include players which are disabled.
  50       *
  51       * @return string[] Array of contentbank contenttypes.
  52       */
  53      public function get_enabled_content_types(): array {
  54          if (!is_null($this->enabledcontenttypes)) {
  55              return $this->enabledcontenttypes;
  56          }
  57  
  58          $enabledtypes = \core\plugininfo\contenttype::get_enabled_plugins();
  59          $types = [];
  60          foreach ($enabledtypes as $name) {
  61              $contenttypeclassname = "\\contenttype_$name\\contenttype";
  62              $contentclassname = "\\contenttype_$name\\content";
  63              if (class_exists($contenttypeclassname) && class_exists($contentclassname)) {
  64                  $types[$contenttypeclassname] = $name;
  65              }
  66          }
  67          return $this->enabledcontenttypes = $types;
  68      }
  69  
  70      /**
  71       * Obtains an array of supported extensions by active plugins.
  72       *
  73       * @return array The array with all the extensions supported and the supporting plugin names.
  74       */
  75      public function load_all_supported_extensions(): array {
  76          $extensionscache = \cache::make('core', 'contentbank_enabled_extensions');
  77          $supportedextensions = $extensionscache->get('enabled_extensions');
  78          if ($supportedextensions === false) {
  79              // Load all enabled extensions.
  80              $supportedextensions = [];
  81              foreach ($this->get_enabled_content_types() as $type) {
  82                  $classname = "\\contenttype_$type\\contenttype";
  83                  $contenttype = new $classname;
  84                  if ($contenttype->is_feature_supported($contenttype::CAN_UPLOAD)) {
  85                      $extensions = $contenttype->get_manageable_extensions();
  86                      foreach ($extensions as $extension) {
  87                          if (array_key_exists($extension, $supportedextensions)) {
  88                              $supportedextensions[$extension][] = $type;
  89                          } else {
  90                              $supportedextensions[$extension] = [$type];
  91                          }
  92                      }
  93                  }
  94              }
  95              $extensionscache->set('enabled_extensions', $supportedextensions);
  96          }
  97          return $supportedextensions;
  98      }
  99  
 100      /**
 101       * Obtains an array of supported extensions in the given context.
 102       *
 103       * @param context $context Optional context to check (default null)
 104       * @return array The array with all the extensions supported and the supporting plugin names.
 105       */
 106      public function load_context_supported_extensions(context $context = null): array {
 107          $extensionscache = \cache::make('core', 'contentbank_context_extensions');
 108  
 109          $contextextensions = $extensionscache->get($context->id);
 110          if ($contextextensions === false) {
 111              $contextextensions = [];
 112              $supportedextensions = $this->load_all_supported_extensions();
 113              foreach ($supportedextensions as $extension => $types) {
 114                  foreach ($types as $type) {
 115                      $classname = "\\contenttype_$type\\contenttype";
 116                      $contenttype = new $classname($context);
 117                      if ($contenttype->can_upload()) {
 118                          $contextextensions[$extension] = $type;
 119                          break;
 120                      }
 121                  }
 122              }
 123              $extensionscache->set($context->id, $contextextensions);
 124          }
 125          return $contextextensions;
 126      }
 127  
 128      /**
 129       * Obtains a string with all supported extensions by active plugins.
 130       * Mainly to use as filepicker options parameter.
 131       *
 132       * @param context $context   Optional context to check (default null)
 133       * @return string A string with all the extensions supported.
 134       */
 135      public function get_supported_extensions_as_string(context $context = null) {
 136          $supported = $this->load_context_supported_extensions($context);
 137          $extensions = array_keys($supported);
 138          return implode(',', $extensions);
 139      }
 140  
 141      /**
 142       * Returns the file extension for a file.
 143       *
 144       * @param  string $filename The name of the file
 145       * @return string The extension of the file
 146       */
 147      public function get_extension(string $filename) {
 148          $dot = strrpos($filename, '.');
 149          if ($dot === false) {
 150              return '';
 151          }
 152          return strtolower(substr($filename, $dot));
 153      }
 154  
 155      /**
 156       * Get the first content bank plugin supports a file extension.
 157       *
 158       * @param string $extension Content file extension
 159       * @param context $context $context     Optional context to check (default null)
 160       * @return string contenttype name supports the file extension or null if the extension is not supported by any allowed plugin.
 161       */
 162      public function get_extension_supporter(string $extension, context $context = null): ?string {
 163          $supporters = $this->load_context_supported_extensions($context);
 164          if (array_key_exists($extension, $supporters)) {
 165              return $supporters[$extension];
 166          }
 167          return null;
 168      }
 169  
 170      /**
 171       * Find the contents with %$search% in the contextid defined.
 172       * If contextid and search are empty, all contents are returned.
 173       * In all the cases, only the contents for the enabled contentbank-type plugins are returned.
 174       * No content-type permissions are validated here. It is the caller responsability to check that the user can access to them.
 175       * The only validation done here is, for each content, a call to the method $content->is_view_allowed().
 176       *
 177       * @param  string|null $search Optional string to search (for now it will search only into the name).
 178       * @param  int $contextid Optional contextid to search.
 179       * @param  array $contenttypenames Optional array with the list of content-type names to search.
 180       * @return array The contents for the enabled contentbank-type plugins having $search as name and placed in $contextid.
 181       */
 182      public function search_contents(?string $search = null, ?int $contextid = 0, ?array $contenttypenames = null): array {
 183          global $DB;
 184  
 185          $contents = [];
 186  
 187          // Get only contents for enabled content-type plugins.
 188          $contenttypes = [];
 189          $enabledcontenttypes = $this->get_enabled_content_types();
 190          foreach ($enabledcontenttypes as $contenttypename) {
 191              if (empty($contenttypenames) || in_array($contenttypename, $contenttypenames)) {
 192                  $contenttypes[] = "contenttype_$contenttypename";
 193              }
 194          }
 195  
 196          if (empty($contenttypes)) {
 197              // Early return if there are no content-type plugins enabled.
 198              return $contents;
 199          }
 200  
 201          list($sqlcontenttypes, $params) = $DB->get_in_or_equal($contenttypes, SQL_PARAMS_NAMED);
 202          $sql = " contenttype $sqlcontenttypes ";
 203  
 204          // Filter contents on this context (if defined).
 205          if (!empty($contextid)) {
 206              $params['contextid'] = $contextid;
 207              $sql .= ' AND contextid = :contextid ';
 208          }
 209  
 210          // Search for contents having this string (if defined).
 211          if (!empty($search)) {
 212              $sql .= ' AND ' . $DB->sql_like('name', ':name', false, false);
 213              $params['name'] = '%' . $DB->sql_like_escape($search) . '%';
 214          }
 215  
 216          $records = $DB->get_records_select('contentbank_content', $sql, $params, 'name ASC');
 217          foreach ($records as $record) {
 218              $content = $this->get_content_from_id($record->id);
 219              if ($content->is_view_allowed()) {
 220                  $contents[] = $content;
 221              }
 222          }
 223  
 224          return $contents;
 225      }
 226  
 227      /**
 228       * Create content from a file information.
 229       *
 230       * @throws file_exception If file operations fail
 231       * @throws dml_exception if the content creation fails
 232       * @param \context $context Context where to upload the file and content.
 233       * @param int $userid Id of the user uploading the file.
 234       * @param stored_file $file The file to get information from
 235       * @return content
 236       */
 237      public function create_content_from_file(\context $context, int $userid, stored_file $file): ?content {
 238          global $USER;
 239          if (empty($userid)) {
 240              $userid = $USER->id;
 241          }
 242          // Get the contenttype to manage given file's extension.
 243          $filename = $file->get_filename();
 244          $extension = $this->get_extension($filename);
 245          $plugin = $this->get_extension_supporter($extension, $context);
 246          $classname = '\\contenttype_'.$plugin.'\\contenttype';
 247          $record = new \stdClass();
 248          $record->name = $filename;
 249          $record->usercreated = $userid;
 250          $contentype = new $classname($context);
 251          $content = $contentype->upload_content($file, $record);
 252          $event = \core\event\contentbank_content_uploaded::create_from_record($content->get_content());
 253          $event->trigger();
 254          return $content;
 255      }
 256  
 257      /**
 258       * Delete content bank content by context.
 259       *
 260       * @param context $context The context to delete content from.
 261       * @return bool
 262       */
 263      public function delete_contents(context $context): bool {
 264          global $DB;
 265  
 266          $result = true;
 267          $records = $DB->get_records('contentbank_content', ['contextid' => $context->id]);
 268          foreach ($records as $record) {
 269              $content = $this->get_content_from_id($record->id);
 270              $contenttype = $content->get_content_type_instance();
 271              if (!$contenttype->delete_content($content)) {
 272                  $result = false;
 273              }
 274          }
 275          return $result;
 276      }
 277  
 278      /**
 279       * Move content bank content from a context to another.
 280       *
 281       * @param context $from The context to get content from.
 282       * @param context $to The context to move content to.
 283       * @return bool
 284       */
 285      public function move_contents(context $from, context $to): bool {
 286          global $DB;
 287  
 288          $result = true;
 289          $records = $DB->get_records('contentbank_content', ['contextid' => $from->id]);
 290          foreach ($records as $record) {
 291              $content = $this->get_content_from_id($record->id);
 292              $contenttype = $content->get_content_type_instance();
 293              if (!$contenttype->move_content($content, $to)) {
 294                  $result = false;
 295              }
 296          }
 297          return $result;
 298      }
 299  
 300      /**
 301       * Get the list of content types that have the requested feature.
 302       *
 303       * @param string $feature Feature code e.g CAN_UPLOAD.
 304       * @param null|\context $context Optional context to check the permission to use the feature.
 305       * @param bool $enabled Whether check only the enabled content types or all of them.
 306       *
 307       * @return string[] List of content types where the user has permission to access the feature.
 308       */
 309      public function get_contenttypes_with_capability_feature(string $feature, \context $context = null, bool $enabled = true): array {
 310          $contenttypes = [];
 311          // Check enabled content types or all of them.
 312          if ($enabled) {
 313              $contenttypestocheck = $this->get_enabled_content_types();
 314          } else {
 315              $plugins = core_plugin_manager::instance()->get_plugins_of_type('contenttype');
 316              foreach ($plugins as $plugin) {
 317                  $contenttypeclassname = "\\{$plugin->type}_{$plugin->name}\\contenttype";
 318                  $contenttypestocheck[$contenttypeclassname] = $plugin->name;
 319              }
 320          }
 321  
 322          foreach ($contenttypestocheck as $classname => $name) {
 323              $contenttype = new $classname($context);
 324              // The method names that check the features permissions must follow the pattern can_feature.
 325              if ($contenttype->{"can_$feature"}()) {
 326                  $contenttypes[$classname] = $name;
 327              }
 328          }
 329  
 330          return $contenttypes;
 331      }
 332  
 333      /**
 334       * Return a content class form a content id.
 335       *
 336       * @throws coding_exception if the ID is not valid or some class does no exists
 337       * @param int $id the content id
 338       * @return content the content class instance
 339       */
 340      public function get_content_from_id(int $id): content {
 341          global $DB;
 342          $record = $DB->get_record('contentbank_content', ['id' => $id], '*', MUST_EXIST);
 343          $contentclass = "\\$record->contenttype\\content";
 344          return new $contentclass($record);
 345      }
 346  
 347      /**
 348       * Whether the context is allowed.
 349       *
 350       * @param context $context Context to check.
 351       * @return bool
 352       */
 353      public function is_context_allowed(context $context): bool {
 354          return in_array($context->contextlevel, self::ALLOWED_CONTEXT_LEVELS);
 355      }
 356  }