lib/dtl/xml_database_exporter.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  * XML format exporter class
  19  *
  20  * @package    core_dtl
  21  * @copyright  2008 Andrei Bautu
  22  * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
  23  */
  24
  25 defined('MOODLE_INTERNAL') || die();
  26
  27 /**
  28  * XML format exporter class.
  29  * Provides logic for writing XML tags and data inside appropriate callbacks.
  30  * Subclasses should define XML data sinks.
  31  */
  32 abstract class xml_database_exporter extends database_exporter {
  33     /**
  34      * Generic output method. Subclasses should implement it with code specific
  35      * to the target XML sink.
  36      */
  37     protected abstract function output($text);
  38
  39     /**
  40      * Callback function. Outputs open XML PI and moodle_database opening tag.
  41      *
  42      * @param float $version the version of the system which generating the data
  43      * @param string $release moodle release info
  44      * @param string $timestamp the timestamp of the data (in ISO 8601) format.
  45      * @param string $description a user description of the data.
  46      * @return void
  47      */
  48     public function begin_database_export($version, $release, $timestamp, $description) {
  49         $this->output('<?xml version="1.0" encoding="utf-8"?>');
  50         //TODO add xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" and schema information
  51         $this->output('<moodle_database version="'.$version.'" release="'.$release.'" timestamp="'.$timestamp.'"'.(empty ($description) ? '' : ' comment="'.htmlspecialchars($description, ENT_QUOTES, 'UTF-8').'"').'>');
  52     }
  53
  54     /**
  55      * Callback function. Outputs table opening tag.
  56      *
  57      * @param xmldb_table $table - XMLDB object for the exported table
  58      * @return void
  59      */
  60     public function begin_table_export(xmldb_table $table) {
  61         $this->output('<table name="'.$table->getName().'" schemaHash="'.$table->getHash().'">');
  62     }
  63
  64     /**
  65      * Callback function. Outputs table closing tag.
  66      *
  67      * @param xmldb_table $table - XMLDB object for the exported table
  68      */
  69     public function finish_table_export(xmldb_table $table) {
  70         $this->output('</table>');
  71     }
  72
  73     /**
  74      * Callback function. Outputs moodle_database closing tag.
  75      */
  76     public function finish_database_export() {
  77         $this->output('</moodle_database>');
  78     }
  79
  80     /**
  81      * Callback function. Outputs record tag with field subtags and data.
  82      *
  83      * @param xmldb_table $table - XMLDB object of the table from which data was retrieved
  84      * @param object $data - data object (fields and values from record)
  85      * @return void
  86      */
  87     public function export_table_data(xmldb_table $table, $data) {
  88         $this->output('<record>');
  89         foreach ($data as $key => $value) {
  90             if (is_null($value)) {
  91                 $this->output('<field name="'.$key.'" value="null" />');
  92             } else {
  93                 $this->output('<field name="'.$key.'">'.htmlspecialchars($value, ENT_NOQUOTES, 'UTF-8').'</field>');
  94             }
  95         }
  96         $this->output('</record>');
  97     }
  98 }