lib/licenselib.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 /**
  20  * A namespace contains license specific functions
  21  *
  22  * @since      Moodle 2.0
  23  * @package    core
  24  * @subpackage lib
  25  * @copyright  2010 Dongsheng Cai <dongsheng@moodle.com>
  26  * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
  27  */
  28
  29 defined('MOODLE_INTERNAL') || die();
  30
  31 class license_manager {
  32
  33     /**
  34      * License is a core license and can not be updated or deleted.
  35      */
  36     const CORE_LICENSE = 0;
  37
  38     /**
  39      * License is a custom license and can be updated and/or deleted.
  40      */
  41     const CUSTOM_LICENSE = 1;
  42
  43     /**
  44      * Integer representation of boolean for a license that is enabled.
  45      */
  46     const LICENSE_ENABLED = 1;
  47
  48     /**
  49      * Integer representation of boolean for a license that is disabled.
  50      */
  51     const LICENSE_DISABLED = 0;
  52
  53     /**
  54      * Integer for moving a license up order.
  55      */
  56     const LICENSE_MOVE_UP = -1;
  57
  58     /**
  59      * Integer for moving a license down order.
  60      */
  61     const LICENSE_MOVE_DOWN = 1;
  62
  63     /**
  64      * Save a license record.
  65      *
  66      * @param object $license {
  67      *            shortname => string a shortname of license, will be refered by files table[required]
  68      *            fullname  => string the fullname of the license [required]
  69      *            source => string the homepage of the license type[required]
  70      *            enabled => int is it enabled?
  71      *            version  => int a version number used by moodle [required]
  72      * }
  73      */
  74     static public function save($license) {
  75
  76         $existinglicense = self::get_license_by_shortname($license->shortname);
  77
  78         if (!empty($existinglicense)) {
  79             $id = $existinglicense->id;
  80             if ($existinglicense->custom == self::CORE_LICENSE) {
  81                 // Can only update the enabled status and sortorder for core licenses.
  82                 $existinglicense->enabled = $license->enabled;
  83                 $existinglicense->sortorder = $license->sortorder;
  84                 $license = $existinglicense;
  85             }
  86             $license->id = $id;
  87             self::update($license);
  88         } else {
  89             self::create($license);
  90         }
  91
  92         return true;
  93     }
  94
  95     /**
  96      * @deprecated Since Moodle 3.9, MDL-45184.
  97      */
  98     public function add() {
  99         throw new coding_exception('license_manager::add() is deprecated. Please use license_manager::save() instead.');
 100     }
 101
 102     /**
 103      * Create a license record.
 104      *
 105      * @param object $license the license to create record for.
 106      */
 107     static protected function create($license) {
 108         global $DB;
 109
 110         $licensecount = count(self::get_licenses());
 111         $license->sortorder = $licensecount + 1;
 112         // Enable all created license by default.
 113         $license->enabled = self::LICENSE_ENABLED;
 114         // API can only create custom licenses, core licenses
 115         // are directly created at install or upgrade.
 116         $license->custom = self::CUSTOM_LICENSE;
 117
 118         $DB->insert_record('license', $license);
 119         self::reset_license_cache();
 120         // Update the config setting of active licenses.
 121         self::set_active_licenses();
 122     }
 123
 124     /**
 125      * Read licens record(s) from database.
 126      *
 127      * @param array $params license parameters to return licenses for.
 128      *
 129      * @return array $filteredlicenses object[] of licenses.
 130      */
 131     static public function read(array $params = []) {
 132         $licenses = self::get_licenses();
 133
 134         $filteredlicenses = [];
 135
 136         foreach ($licenses as $shortname => $license) {
 137             $filtermatch = true;
 138             foreach ($params as $key => $value) {
 139                 if ($license->$key != $value) {
 140                     $filtermatch = false;
 141                 }
 142             }
 143             if ($filtermatch) {
 144                 $filteredlicenses[$shortname] = $license;
 145             }
 146         }
 147         return $filteredlicenses;
 148
 149     }
 150
 151     /**
 152      * Update a license record.
 153      *
 154      * @param object $license the license to update record for.
 155      *
 156      * @throws \moodle_exception if attempting to update a core license.
 157      */
 158     static protected function update($license) {
 159         global $DB;
 160
 161         $DB->update_record('license', $license);
 162         self::reset_license_cache();
 163     }
 164
 165     /**
 166      * Delete a custom license.
 167      *
 168      * @param string $licenseshortname the shortname of license.
 169      *
 170      * @throws \moodle_exception when attempting to delete a license you are not allowed to.
 171      */
 172     static public function delete($licenseshortname) {
 173         global $DB;
 174
 175         $licensetodelete = self::get_license_by_shortname($licenseshortname);
 176
 177         if (!empty($licensetodelete)) {
 178             if ($licensetodelete->custom == self::CUSTOM_LICENSE) {
 179                 // Check that the license is not in use by any files, if so it cannot be deleted.
 180                 $countfilesusinglicense = $DB->count_records('files', ['license' => $licenseshortname]);
 181                 if ($countfilesusinglicense > 0) {
 182                     throw new moodle_exception('cannotdeletelicenseinuse', 'license');
 183                 }
 184                 $deletedsortorder = $licensetodelete->sortorder;
 185                 $DB->delete_records('license', ['id' => $licensetodelete->id]);
 186
 187                 // We've deleted a license, so update our list of licenses so we don't save the deleted license again.
 188                 self::reset_license_cache();
 189                 $licenses = self::get_licenses();
 190
 191                 foreach ($licenses as $license) {
 192                     if ($license->sortorder > $deletedsortorder) {
 193                         $license->sortorder = $license->sortorder - 1;
 194                         self::save($license);
 195                     }
 196                 }
 197
 198                 // Update the config setting of active licenses as well.
 199                 self::set_active_licenses();
 200
 201             } else {
 202                 throw new moodle_exception('cannotdeletecore', 'license');
 203             }
 204         } else {
 205             throw new moodle_exception('licensenotfoundshortname', 'license', $licenseshortname);
 206         }
 207     }
 208
 209     /**
 210      * Get license records.
 211      *
 212      * @return array|false object[] of license records of false if none.
 213      */
 214     static public function get_licenses() {
 215         global $DB;
 216
 217         $cache = \cache::make('core', 'license');
 218         $licenses = $cache->get('licenses');
 219
 220         if ($licenses === false) {
 221             $licenses = [];
 222             $records = $DB->get_records_select('license', null, null, 'sortorder ASC');
 223             foreach ($records as $license) {
 224                 $licenses[$license->shortname] = $license;
 225             }
 226             $cache->set('licenses', $licenses);
 227         }
 228
 229         foreach ($licenses as $license) {
 230             // Localise the license names.
 231             if ($license->custom == self::CORE_LICENSE) {
 232                 $license->fullname = get_string($license->shortname, 'core_license');
 233             } else {
 234                 $license->fullname = format_string($license->fullname);
 235             }
 236         }
 237
 238         return $licenses;
 239     }
 240
 241     /**
 242      * Change the sort order of a license (and it's sibling license as a result).
 243      *
 244      * @param int $direction value to change sortorder of license by.
 245      * @param string $licenseshortname the shortname of license to changes sortorder for.
 246      *
 247      * @throws \moodle_exception if attempting to use invalid direction value.
 248      */
 249     static public function change_license_sortorder(int $direction, string $licenseshortname) : void {
 250
 251         if ($direction != self::LICENSE_MOVE_UP && $direction != self::LICENSE_MOVE_DOWN) {
 252             throw new coding_exception(
 253                 'Must use a valid licence API move direction constant (LICENSE_MOVE_UP or LICENSE_MOVE_DOWN)');
 254         }
 255
 256         $licenses = self::get_licenses();
 257         $licensetoupdate = $licenses[$licenseshortname];
 258
 259         $currentsortorder = $licensetoupdate->sortorder;
 260         $targetsortorder = $currentsortorder + $direction;
 261
 262         if ($targetsortorder > 0 && $targetsortorder <= count($licenses) ) {
 263             foreach ($licenses as $license) {
 264                 if ($license->sortorder == $targetsortorder) {
 265                     $license->sortorder = $license->sortorder - $direction;
 266                     self::update($license);
 267                 }
 268             }
 269             $licensetoupdate->sortorder = $targetsortorder;
 270             self::update($licensetoupdate);
 271         }
 272     }
 273
 274     /**
 275      * Get license record by shortname
 276      *
 277      * @param string $name the shortname of license
 278      * @return object|null the license or null if no license found.
 279      */
 280     static public function get_license_by_shortname(string $name) {
 281         $licenses = self::read(['shortname' => $name]);
 282
 283         if (!empty($licenses)) {
 284             $license = reset($licenses);
 285         } else {
 286             $license = null;
 287         }
 288
 289         return $license;
 290     }
 291
 292     /**
 293      * Enable a license
 294      * @param string $license the shortname of license
 295      * @return boolean
 296      */
 297     static public function enable($license) {
 298         if ($license = self::get_license_by_shortname($license)) {
 299             $license->enabled = self::LICENSE_ENABLED;
 300             self::update($license);
 301         }
 302         self::set_active_licenses();
 303
 304         return true;
 305     }
 306
 307     /**
 308      * Disable a license
 309      * @param string $license the shortname of license
 310      * @return boolean
 311      */
 312     static public function disable($license) {
 313         global $CFG;
 314         // Site default license cannot be disabled!
 315         if ($license == $CFG->sitedefaultlicense) {
 316             throw new \moodle_exception('error');
 317         }
 318         if ($license = self::get_license_by_shortname($license)) {
 319             $license->enabled = self::LICENSE_DISABLED;
 320             self::update($license);
 321         }
 322         self::set_active_licenses();
 323
 324         return true;
 325     }
 326
 327     /**
 328      * Store active licenses in global config.
 329      */
 330     static protected function set_active_licenses() {
 331         $licenses = self::read(['enabled' => self::LICENSE_ENABLED]);
 332         $result = array();
 333         foreach ($licenses as $l) {
 334             $result[] = $l->shortname;
 335         }
 336         set_config('licenses', implode(',', $result));
 337     }
 338
 339     /**
 340      * Get the globally configured active licenses.
 341      *
 342      * @return array of license objects.
 343      * @throws \coding_exception
 344      */
 345     static public function get_active_licenses() {
 346         global $CFG;
 347
 348         $result = [];
 349
 350         if (!empty($CFG->licenses)) {
 351             $activelicenses = explode(',', $CFG->licenses);
 352             $licenses = self::get_licenses();
 353             foreach ($licenses as $license) {
 354                 if (in_array($license->shortname, $activelicenses)) {
 355                     $result[$license->shortname] = $license;
 356                 }
 357             }
 358         }
 359
 360         return $result;
 361     }
 362
 363     /**
 364      * Get the globally configured active licenses as an array.
 365      *
 366      * @return array $licenses an associative array of licenses shaped as ['shortname' => 'fullname']
 367      */
 368     static public function get_active_licenses_as_array() {
 369         $activelicenses = self::get_active_licenses();
 370
 371         $licenses = [];
 372         foreach ($activelicenses as $license) {
 373             $licenses[$license->shortname] = $license->fullname;
 374         }
 375
 376         return $licenses;
 377     }
 378
 379     /**
 380      * Install moodle built-in licenses.
 381      */
 382     static public function install_licenses() {
 383         global $CFG;
 384
 385         require_once($CFG->libdir . '/db/upgradelib.php');
 386
 387         upgrade_core_licenses();
 388     }
 389
 390     /**
 391      * Reset the license cache so it rebuilds next time licenses are fetched.
 392      */
 393     static public function reset_license_cache() {
 394         $cache = \cache::make('core', 'license');
 395         $cache->delete('licenses');
 396     }
 397 }