PHP stored_file::get_repository_id方法代码示例

    /**
     * Performs synchronisation of an external file if the previous one has expired.
     *
     * This function must be implemented for external repositories supporting
     * FILE_REFERENCE, it is called for existing aliases when their filesize,
     * contenthash or timemodified are requested. It is not called for internal
     * repositories (see {@link repository::has_moodle_files()}), references to
     * internal files are updated immediately when source is modified.
     *
     * Referenced files may optionally keep their content in Moodle filepool (for
     * thumbnail generation or to be able to serve cached copy). In this
     * case both contenthash and filesize need to be synchronized. Otherwise repositories
     * should use contenthash of empty file and correct filesize in bytes.
     *
     * Note that this function may be run for EACH file that needs to be synchronised at the
     * moment. If anything is being downloaded or requested from external sources there
     * should be a small timeout. The synchronisation is performed to update the size of
     * the file and/or to update image and re-generated image preview. There is nothing
     * fatal if syncronisation fails but it is fatal if syncronisation takes too long
     * and hangs the script generating a page.
     *
     * Note: If you wish to call $file->get_filesize(), $file->get_contenthash() or
     * $file->get_timemodified() make sure that recursion does not happen.
     *
     * Called from {@link stored_file::sync_external_file()}
     *
     * @uses stored_file::set_missingsource()
     * @uses stored_file::set_synchronized()
     * @param stored_file $file
     * @return bool false when file does not need synchronisation, true if it was synchronised
     */
    public function sync_reference(stored_file $file) {
        if ($file->get_repository_id() != $this->id) {
            // This should not really happen because the function can be called from stored_file only.
            return false;
        }

        if ($this->has_moodle_files()) {
            // References to local files need to be synchronised only once.
            // Later they will be synchronised automatically when the source is changed.
            if ($file->get_referencelastsync()) {
                return false;
            }
            $fs = get_file_storage();
            $params = file_storage::unpack_reference($file->get_reference(), true);
            if (!is_array($params) || !($storedfile = $fs->get_file($params['contextid'],
                    $params['component'], $params['filearea'], $params['itemid'], $params['filepath'],
                    $params['filename']))) {
                $file->set_missingsource();
            } else {
                $file->set_synchronized($storedfile->get_contenthash(), $storedfile->get_filesize());
            }
            return true;
        }

        // Backward compatibility (Moodle 2.3-2.5) implementation that calls
        // methods repository::get_reference_file_lifetime(), repository::sync_individual_file()
        // and repository::get_file_by_reference(). These methods are removed from the
        // base repository class but may still be implemented by the child classes.

        // THIS IS NOT A GOOD EXAMPLE of implementation. For good examples see the overwriting methods.

        if (!method_exists($this, 'get_file_by_reference')) {
            // Function get_file_by_reference() is not implemented. No synchronisation.
            return false;
        }

        // Check if the previous sync result is still valid.
        if (method_exists($this, 'get_reference_file_lifetime')) {
            $lifetime = $this->get_reference_file_lifetime($file->get_reference());
        } else {
            // Default value that was hardcoded in Moodle 2.3 - 2.5.
            $lifetime =  60 * 60 * 24;
        }
        if (($lastsynced = $file->get_referencelastsync()) && $lastsynced + $lifetime >= time()) {
            return false;
        }

        $cache = cache::make('core', 'repositories');
        if (($lastsyncresult = $cache->get('sync:'.$file->get_referencefileid())) !== false) {
            if ($lastsyncresult === true) {
                // We are in the process of synchronizing this reference.
                // Avoid recursion when calling $file->get_filesize() and $file->get_contenthash().
                return false;
            } else {
                // We have synchronised the same reference inside this request already.
                // It looks like the object $file was created before the synchronisation and contains old data.
                if (!empty($lastsyncresult['missing'])) {
                    $file->set_missingsource();
                } else {
                    $cache->set('sync:'.$file->get_referencefileid(), true);
                    if ($file->get_contenthash() != $lastsyncresult['contenthash'] ||
                            $file->get_filesize() != $lastsyncresult['filesize']) {
                        $file->set_synchronized($lastsyncresult['contenthash'], $lastsyncresult['filesize']);
                    }
                    $cache->set('sync:'.$file->get_referencefileid(), $lastsyncresult);
                }
                return true;
            }
        }
//.........这里部分代码省略.........

 /**
  * Performs synchronisation of an external file if the previous one has expired.
  *
  * This function must be implemented for external repositories supporting
  * FILE_REFERENCE, it is called for existing aliases when their filesize,
  * contenthash or timemodified are requested. It is not called for internal
  * repositories (see {@link repository::has_moodle_files()}), references to
  * internal files are updated immediately when source is modified.
  *
  * Referenced files may optionally keep their content in Moodle filepool (for
  * thumbnail generation or to be able to serve cached copy). In this
  * case both contenthash and filesize need to be synchronized. Otherwise repositories
  * should use contenthash of empty file and correct filesize in bytes.
  *
  * Note that this function may be run for EACH file that needs to be synchronised at the
  * moment. If anything is being downloaded or requested from external sources there
  * should be a small timeout. The synchronisation is performed to update the size of
  * the file and/or to update image and re-generated image preview. There is nothing
  * fatal if syncronisation fails but it is fatal if syncronisation takes too long
  * and hangs the script generating a page.
  *
  * Note: If you wish to call $file->get_filesize(), $file->get_contenthash() or
  * $file->get_timemodified() make sure that recursion does not happen.
  *
  * Called from {@link stored_file::sync_external_file()}
  *
  * @uses stored_file::set_missingsource()
  * @uses stored_file::set_synchronized()
  * @param stored_file $file
  * @return bool false when file does not need synchronisation, true if it was synchronised
  */
 public function sync_reference(stored_file $file)
 {
     if ($file->get_repository_id() != $this->id) {
         // This should not really happen because the function can be called from stored_file only.
         return false;
     }
     if ($this->has_moodle_files()) {
         // References to local files need to be synchronised only once.
         // Later they will be synchronised automatically when the source is changed.
         if ($file->get_referencelastsync()) {
             return false;
         }
         $fs = get_file_storage();
         $params = file_storage::unpack_reference($file->get_reference(), true);
         if (!is_array($params) || !($storedfile = $fs->get_file($params['contextid'], $params['component'], $params['filearea'], $params['itemid'], $params['filepath'], $params['filename']))) {
             $file->set_missingsource();
         } else {
             $file->set_synchronized($storedfile->get_contenthash(), $storedfile->get_filesize(), 0, $storedfile->get_timemodified());
         }
         return true;
     }
     return false;
 }

 /**
  * Downloads the file from external repository and saves it in moodle filepool.
  * This function is different from {@link repository::sync_external_file()} because it has
  * bigger request timeout and always downloads the content.
  *
  * This function is invoked when we try to unlink the file from the source and convert
  * a reference into a true copy.
  *
  * @throws exception when file could not be imported
  *
  * @param stored_file $file
  * @param int $maxbytes throw an exception if file size is bigger than $maxbytes (0 means no limit)
  */
 public function import_external_file_contents(stored_file $file, $maxbytes = 0)
 {
     if (!$file->is_external_file()) {
         // nothing to import if the file is not a reference
         return;
     } else {
         if ($file->get_repository_id() != $this->id) {
             // error
             debugging('Repository instance id does not match');
             return;
         } else {
             if ($this->has_moodle_files()) {
                 // files that are references to local files are already in moodle filepool
                 // just validate the size
                 if ($maxbytes > 0 && $file->get_filesize() > $maxbytes) {
                     throw new file_exception('maxbytes');
                 }
                 return;
             } else {
                 if ($maxbytes > 0 && $file->get_filesize() > $maxbytes) {
                     // note that stored_file::get_filesize() also calls synchronisation
                     throw new file_exception('maxbytes');
                 }
                 $fs = get_file_storage();
                 $contentexists = $fs->content_exists($file->get_contenthash());
                 if ($contentexists && $file->get_filesize() && $file->get_contenthash() === sha1('')) {
                     // even when 'file_storage::content_exists()' returns true this may be an empty
                     // content for the file that was not actually downloaded
                     $contentexists = false;
                 }
                 $now = time();
                 if ($file->get_referencelastsync() + $file->get_referencelifetime() >= $now && !$file->get_status() && $contentexists) {
                     // we already have the content in moodle filepool and it was synchronised recently.
                     // Repositories may overwrite it if they want to force synchronisation anyway!
                     return;
                 } else {
                     // attempt to get a file
                     try {
                         $fileinfo = $this->get_file($file->get_reference());
                         if (isset($fileinfo['path'])) {
                             list($contenthash, $filesize, $newfile) = $fs->add_file_to_pool($fileinfo['path']);
                             // set this file and other similar aliases synchronised
                             $lifetime = $this->get_reference_file_lifetime($file->get_reference());
                             $file->set_synchronized($contenthash, $filesize, 0, $lifetime);
                         } else {
                             throw new moodle_exception('errorwhiledownload', 'repository', '', '');
                         }
                     } catch (Exception $e) {
                         if ($contentexists) {
                             // better something than nothing. We have a copy of file. It's sync time
                             // has expired but it is still very likely that it is the last version
                         } else {
                             throw $e;
                         }
                     }
                 }
             }
         }
     }
 }