repository/s3/lib.php

   1 <?php
   2
   3 // This file is part of Moodle - http://moodle.org/
   4 //
   5 // Moodle is free software: you can redistribute it and/or modify
   6 // it under the terms of the GNU General Public License as published by
   7 // the Free Software Foundation, either version 3 of the License, or
   8 // (at your option) any later version.
   9 //
  10 // Moodle is distributed in the hope that it will be useful,
  11 // but WITHOUT ANY WARRANTY; without even the implied warranty of
  12 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13 // GNU General Public License for more details.
  14 //
  15 // You should have received a copy of the GNU General Public License
  16 // along with Moodle.  If not, see <http://www.gnu.org/licenses/>.
  17
  18 /**
  19  * This plugin is used to access s3 files
  20  *
  21  * @since 2.0
  22  * @package    repository_s3
  23  * @copyright  2010 Dongsheng Cai {@link http://dongsheng.org}
  24  * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
  25  */
  26 require_once($CFG->dirroot . '/repository/lib.php');
  27 require_once($CFG->dirroot . '/repository/s3/S3.php');
  28
  29 /**
  30  * This is a repository class used to browse Amazon S3 content.
  31  *
  32  * @since 2.0
  33  * @package    repository_s3
  34  * @copyright  2009 Dongsheng Cai {@link http://dongsheng.org}
  35  * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
  36  */
  37 class repository_s3 extends repository {
  38
  39     /**
  40      * Constructor
  41      * @param int $repositoryid
  42      * @param object $context
  43      * @param array $options
  44      */
  45     public function __construct($repositoryid, $context = SYSCONTEXTID, $options = array()) {
  46         parent::__construct($repositoryid, $context, $options);
  47         $this->access_key = get_config('s3', 'access_key');
  48         $this->secret_key = get_config('s3', 'secret_key');
  49         $this->s = new S3($this->access_key, $this->secret_key);
  50         $this->s->setExceptions(true);
  51     }
  52
  53     /**
  54      * Extracts the Bucket and URI from the path
  55      *
  56      * @param string $path path in this format 'bucket/path/to/folder/and/file'
  57      * @return array including bucket and uri
  58      */
  59     protected function explode_path($path) {
  60         $parts = explode('/', $path, 2);
  61         if (isset($parts[1]) && $parts[1] !== '') {
  62             list($bucket, $uri) = $parts;
  63         } else {
  64             $bucket = $parts[0];
  65             $uri = '';
  66         }
  67         return array($bucket, $uri);
  68     }
  69
  70     /**
  71      * Get S3 file list
  72      *
  73      * @param string $path
  74      * @return array The file list and options
  75      */
  76     public function get_listing($path = '', $page = '') {
  77         global $CFG, $OUTPUT;
  78         if (empty($this->access_key)) {
  79             throw new moodle_exception('needaccesskey', 'repository_s3');
  80         }
  81
  82         $list = array();
  83         $list['list'] = array();
  84         $list['path'] = array(
  85             array('name' => get_string('pluginname', 'repository_s3'), 'path' => '')
  86         );
  87
  88         // the management interface url
  89         $list['manage'] = false;
  90         // dynamically loading
  91         $list['dynload'] = true;
  92         // the current path of this list.
  93         // set to true, the login link will be removed
  94         $list['nologin'] = true;
  95         // set to true, the search button will be removed
  96         $list['nosearch'] = true;
  97
  98         $tree = array();
  99
 100         if (empty($path)) {
 101             try {
 102                 $buckets = $this->s->listBuckets();
 103             } catch (S3Exception $e) {
 104                 throw new moodle_exception('errorwhilecommunicatingwith', 'repository', '', $this->get_name());
 105             }
 106             foreach ($buckets as $bucket) {
 107                 $folder = array(
 108                     'title' => $bucket,
 109                     'children' => array(),
 110                     'thumbnail' => $OUTPUT->pix_url(file_folder_icon(90))->out(false),
 111                     'path' => $bucket
 112                     );
 113                 $tree[] = $folder;
 114             }
 115         } else {
 116             $files = array();
 117             $folders = array();
 118             list($bucket, $uri) = $this->explode_path($path);
 119
 120             try {
 121                 $contents = $this->s->getBucket($bucket, $uri, null, null, '/', true);
 122             } catch (S3Exception $e) {
 123                 throw new moodle_exception('errorwhilecommunicatingwith', 'repository', '', $this->get_name());
 124             }
 125             foreach ($contents as $object) {
 126
 127                 // If object has a prefix, it is a 'CommonPrefix', which we consider a folder
 128                 if (isset($object['prefix'])) {
 129                     $title = rtrim($object['prefix'], '/');
 130                 } else {
 131                     $title = $object['name'];
 132                 }
 133
 134                 // Removes the prefix (folder path) from the title
 135                 if (strlen($uri) > 0) {
 136                     $title = substr($title, strlen($uri));
 137                     // Check if title is empty and not zero
 138                     if (empty($title) && !is_numeric($title)) {
 139                         // Amazon returns the prefix itself, we skip it
 140                         continue;
 141                     }
 142                 }
 143
 144                 // This is a so-called CommonPrefix, we consider it as a folder
 145                 if (isset($object['prefix'])) {
 146                     $folders[] = array(
 147                         'title' => $title,
 148                         'children' => array(),
 149                         'thumbnail'=> $OUTPUT->pix_url(file_folder_icon(90))->out(false),
 150                         'path' => $bucket . '/' . $object['prefix']
 151                     );
 152                 } else {
 153                     $files[] = array(
 154                         'title' => $title,
 155                         'size' => $object['size'],
 156                         'datemodified' => $object['time'],
 157                         'source' => $bucket . '/' . $object['name'],
 158                         'thumbnail' => $OUTPUT->pix_url(file_extension_icon($title, 90))->out(false)
 159                     );
 160                 }
 161             }
 162             $tree = array_merge($folders, $files);
 163         }
 164
 165         $trail = '';
 166         if (!empty($path)) {
 167             $parts = explode('/', $path);
 168             if (count($parts) > 1) {
 169                 foreach ($parts as $part) {
 170                     if (!empty($part)) {
 171                         $trail .= $part . '/';
 172                         $list['path'][] = array('name' => $part, 'path' => $trail);
 173                     }
 174                 }
 175             } else {
 176                 $list['path'][] = array('name' => $path, 'path' => $path);
 177             }
 178         }
 179
 180         $list['list'] = $tree;
 181
 182         return $list;
 183     }
 184
 185     /**
 186      * Download S3 files to moodle
 187      *
 188      * @param string $filepath
 189      * @param string $file The file path in moodle
 190      * @return array The local stored path
 191      */
 192     public function get_file($filepath, $file = '') {
 193         list($bucket, $uri) = $this->explode_path($filepath);
 194         $path = $this->prepare_file($file);
 195         try {
 196             $this->s->getObject($bucket, $uri, $path);
 197         } catch (S3Exception $e) {
 198             throw new moodle_exception('errorwhilecommunicatingwith', 'repository', '', $this->get_name());
 199         }
 200         return array('path' => $path);
 201     }
 202
 203     /**
 204      * Return the source information
 205      *
 206      * @param stdClass $filepath
 207      * @return string
 208      */
 209     public function get_file_source_info($filepath) {
 210         return 'Amazon S3: ' . $filepath;
 211     }
 212
 213     /**
 214      * S3 doesn't require login
 215      *
 216      * @return bool
 217      */
 218     public function check_login() {
 219         return true;
 220     }
 221
 222     /**
 223      * S3 doesn't provide search
 224      *
 225      * @return bool
 226      */
 227     public function global_search() {
 228         return false;
 229     }
 230
 231     public static function get_type_option_names() {
 232         return array('access_key', 'secret_key', 'pluginname');
 233     }
 234
 235     public static function type_config_form($mform, $classname = 'repository') {
 236         parent::type_config_form($mform);
 237         $strrequired = get_string('required');
 238         $mform->addElement('text', 'access_key', get_string('access_key', 'repository_s3'));
 239         $mform->addElement('text', 'secret_key', get_string('secret_key', 'repository_s3'));
 240         $mform->addRule('access_key', $strrequired, 'required', null, 'client');
 241         $mform->addRule('secret_key', $strrequired, 'required', null, 'client');
 242     }
 243
 244     /**
 245      * S3 plugins doesn't support return links of files
 246      *
 247      * @return int
 248      */
 249     public function supported_returntypes() {
 250         return FILE_INTERNAL;
 251     }
 252 }