lib/xmldb/xmldb_file.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 class represent one XMLDB file
  19  *
  20  * @package    core_xmldb
  21  * @copyright  1999 onwards Martin Dougiamas     http://dougiamas.com
  22  *             2001-3001 Eloy Lafuente (stronk7) http://contiento.com
  23  * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
  24  */
  25
  26 defined('MOODLE_INTERNAL') || die();
  27
  28
  29 class xmldb_file extends xmldb_object {
  30
  31     /** @var string path to file */
  32     protected $path;
  33
  34     /** @var string path to schema */
  35     protected $schema;
  36
  37     /** @var  string document dtd */
  38     protected $dtd;
  39
  40     /** @var xmldb_structure the structure stored in file */
  41     protected $xmldb_structure;
  42
  43     /**
  44      * Constructor of the xmldb_file
  45      * @param string $path
  46      */
  47     public function __construct($path) {
  48         parent::__construct($path);
  49         $this->path = $path;
  50         $this->xmldb_structure = null;
  51     }
  52
  53     /**
  54      * Determine if the XML file exists
  55      * @return bool
  56      */
  57     public function fileExists() {
  58         if (file_exists($this->path) && is_readable($this->path)) {
  59             return true;
  60         }
  61         return false;
  62     }
  63
  64     /**
  65      * Determine if the XML is writeable
  66      * @return bool
  67      */
  68     public function fileWriteable() {
  69         if (is_writeable(dirname($this->path))) {
  70             return true;
  71         }
  72         return false;
  73     }
  74
  75     public function getStructure() {
  76         return $this->xmldb_structure;
  77     }
  78
  79     /**
  80      * This function will check/validate the XML file for correctness
  81      * Dynamically if will use the best available checker/validator
  82      * (expat syntax checker or DOM schema validator
  83      * @return true
  84      */
  85     public function validateXMLStructure() {
  86
  87         // Create and load XML file
  88         $parser = new DOMDocument();
  89         $contents = file_get_contents($this->path);
  90         if (strpos($contents, '<STATEMENTS>')) {
  91             //delete the removed STATEMENTS section, it would not validate
  92             $contents = preg_replace('|<STATEMENTS>.*</STATEMENTS>|s', '', $contents);
  93         }
  94
  95         // Let's capture errors
  96         $olderrormode = libxml_use_internal_errors(true);
  97
  98         // Clear XML error flag so that we don't incorrectly report failure
  99         // when a previous xml parse failed
 100         libxml_clear_errors();
 101
 102         $parser->loadXML($contents);
 103         // Only validate if we have a schema
 104         if (!empty($this->schema) && file_exists($this->schema)) {
 105             $parser->schemaValidate($this->schema);
 106         }
 107         // Check for errors
 108         $errors = libxml_get_errors();
 109
 110         // Stop capturing errors
 111         libxml_use_internal_errors($olderrormode);
 112
 113         // Prepare errors
 114         if (!empty($errors)) {
 115             // Create one structure to store errors
 116             $structure = new xmldb_structure($this->path);
 117             // Add errors to structure
 118             $structure->errormsg = 'XML Error: ';
 119             foreach ($errors as $error) {
 120                 $structure->errormsg .= sprintf("%s at line %d. ",
 121                                                  trim($error->message, "\n\r\t ."),
 122                                                  $error->line);
 123             }
 124             // Add structure to file
 125             $this->xmldb_structure = $structure;
 126             // Check has failed
 127             return false;
 128         }
 129
 130         return true;
 131     }
 132
 133     /**
 134      * Load and the XMLDB structure from file
 135      * @return true
 136      */
 137     public function loadXMLStructure() {
 138         if ($this->fileExists()) {
 139             // Let's validate the XML file
 140             if (!$this->validateXMLStructure()) {
 141                 return false;
 142             }
 143             $contents = file_get_contents($this->path);
 144             if (strpos($contents, '<STATEMENTS>')) {
 145                 //delete the removed STATEMENTS section, it would not validate
 146                 $contents = preg_replace('|<STATEMENTS>.*</STATEMENTS>|s', '', $contents);
 147                 debugging('STATEMENTS section is not supported any more, please use db/install.php or db/log.php');
 148             }
 149             // File exists, so let's process it
 150             // Load everything to a big array
 151             $xmlarr = xmlize($contents);
 152             // Convert array to xmldb structure
 153             $this->xmldb_structure = $this->arr2xmldb_structure($xmlarr);
 154             // Analyze results
 155             if ($this->xmldb_structure->isLoaded()) {
 156                 $this->loaded = true;
 157                 return true;
 158             } else {
 159                 return false;
 160             }
 161         }
 162         return true;
 163     }
 164
 165     /**
 166      * This function takes an xmlized array and put it into one xmldb_structure
 167      * @param array $xmlarr
 168      * @return xmldb_structure
 169      */
 170     public function arr2xmldb_structure ($xmlarr) {
 171         $structure = new xmldb_structure($this->path);
 172         $structure->arr2xmldb_structure($xmlarr);
 173         return $structure;
 174     }
 175
 176     /**
 177      * This function sets the DTD of the XML file
 178      * @param string
 179      */
 180     public function setDTD($path) {
 181         $this->dtd = $path;
 182     }
 183
 184     /**
 185      * This function sets the schema of the XML file
 186      * @param string
 187      */
 188     public function setSchema($path) {
 189         $this->schema = $path;
 190     }
 191
 192     /**
 193      * This function saves the whole xmldb_structure to its file
 194      * @return int|bool false on failure, number of written bytes on success
 195      */
 196     public function saveXMLFile() {
 197
 198         $structure = $this->getStructure();
 199
 200         $result = file_put_contents($this->path, $structure->xmlOutput());
 201
 202         return $result;
 203     }
 204 }