privacy/classes/local/request/writer.php

   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  * This file contains the interface required to implmeent a content writer.
  19  *
  20  * @package core_privacy
  21  * @copyright 2018 Andrew Nicols <andrew@nicols.co.uk>
  22  * @license http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
  23  */
  24 namespace core_privacy\local\request;
  25
  26 defined('MOODLE_INTERNAL') || die();
  27
  28 /**
  29  * The writer factory class used to fetch and work with the content_writer.
  30  *
  31  * @copyright 2018 Andrew Nicols <andrew@nicols.co.uk>
  32  * @license     http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
  33  */
  34 class writer {
  35     /**
  36      * @var writer The singleton instance of this writer.
  37      */
  38     protected static $instance = null;
  39
  40     /**
  41      * @var content_writer The current content_writer instance.
  42      */
  43     protected $realwriter = null;
  44
  45     /**
  46      * Constructor for the content writer.
  47      *
  48      * Protected to prevent direct instantiation.
  49      */
  50     protected function __construct() {
  51     }
  52
  53     /**
  54      * Singleton to return or create and return a copy of a content_writer.
  55      *
  56      * @return  content_writer
  57      */
  58     protected function get_writer_instance() : content_writer {
  59         if (null === $this->realwriter) {
  60             if (PHPUNIT_TEST) {
  61                 $this->realwriter = new \core_privacy\tests\request\content_writer(static::instance());
  62             } else {
  63                 $this->realwriter = new moodle_content_writer(static::instance());
  64             }
  65         }
  66
  67         return $this->realwriter;
  68     }
  69
  70     /**
  71      * Create a real content_writer for use by PHPUnit tests,
  72      * where a mock writer will not suffice.
  73      *
  74      * @return  content_writer
  75      */
  76     public static function setup_real_writer_instance() {
  77         if (!PHPUNIT_TEST) {
  78             throw new coding_exception('setup_real_writer_instance() is only for use with PHPUnit tests.');
  79         }
  80
  81         $instance = static::instance();
  82
  83         if (null === $instance->realwriter) {
  84             $instance->realwriter = new moodle_content_writer(static::instance());
  85         }
  86     }
  87
  88     /**
  89      * Return an instance of
  90      */
  91     protected static final function instance() {
  92         if (null === self::$instance) {
  93             self::$instance = new static();
  94         }
  95
  96         return self::$instance;
  97     }
  98
  99     /**
 100      * Reset the writer and content_writer.
 101      */
 102     public static final function reset() {
 103         static::$instance = null;
 104     }
 105
 106     /**
 107      * Provide an instance of the writer with the specified context applied.
 108      *
 109      * @param   \context        $context    The context to apply
 110      * @return  content_writer              The content_writer
 111      */
 112     public static function with_context(\context $context) : content_writer {
 113         return static::instance()
 114             ->get_writer_instance()
 115             ->set_context($context);
 116     }
 117
 118     /**
 119      * Export the specified user preference.
 120      *
 121      * @param   string          $component  The name of the component.
 122      * @param   string          $key        The name of th key to be exported.
 123      * @param   string          $value      The value of the preference
 124      * @param   string          $description    A description of the value
 125      * @return  content_writer
 126      */
 127     public static function export_user_preference(
 128         string $component,
 129         string $key,
 130         string $value,
 131         string $description
 132     ) : content_writer {
 133         return static::with_context(\context_system::instance())
 134             ->export_user_preference($component, $key, $value, $description);
 135     }
 136 }