Proyectos de Subversion Moodle

<?php

// This file is part of Moodle - http://moodle.org/

//

// Moodle is free software: you can redistribute it and/or modify

// it under the terms of the GNU General Public License as published by

// the Free Software Foundation, either version 3 of the License, or

// (at your option) any later version.

//

// Moodle is distributed in the hope that it will be useful,

// but WITHOUT ANY WARRANTY; without even the implied warranty of

// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

// GNU General Public License for more details.

//

// You should have received a copy of the GNU General Public License

// along with Moodle.  If not, see <http://www.gnu.org/licenses/>.

/**

 * Code for parsing xml files.

 *

 * Handles functionality for:

 *

 * Import of xml files in questionbank and course import.

 * Can handle xml files larger than 10MB through chunking the input file.

 * Replaces the original xmlize by Hans Anderson, {@link http://www.hansanderson.com/contact/}

 * with equal interface.

 *

 * @package    core

 * @subpackage lib

 * @copyright  Kilian Singer

 * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later

 */

/**

 * Exception thrown when there is an error parsing an XML file.

 *

 * @copyright 2010 The Open University

 * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later

 */

defined('MOODLE_INTERNAL') || die();

class xml_format_exception extends moodle_exception {

    /** @var string */

    public $errorstring;

    /** @var string */

    public $char;

    /**

     * Constructor function

     *

     * @param string $errorstring Errorstring

     * @param int $line Linenumber

     * @param string $char Errorcharacter

     * @param string $link Link

     */

    public function __construct($errorstring, $line, $char, $link = '') {

        $this->errorstring = $errorstring;

        $this->line = $line;

        $this->char = $char;

        $a = new stdClass();

        $a->errorstring = $errorstring;

        $a->errorline = $line;

        $a->errorchar = $char;

        parent::__construct('errorparsingxml', 'error', $link, $a);

    }

}

/**

 * Class for parsing xml files.

 *

 * Handles functionality for:

 *

 * Import of xml files in questionbank and course import.

 * Can handle xml files larger than 10MB through chunking the input file.

 * Uses a similar interface to the original version xmlize() by Hans Anderson.

 *

 * @package    core

 * @subpackage lib

 * @copyright  Kilian Singer

 * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later

 */

class core_xml_parser {

    /** @var array resulting $xml tree */

    private $xml;

    /** @var array stores references to constructed $xml tree */

    private $current;

    /** @var int tores the level in the XML tree */

    private $level;

    /**

     * Is called when tags are opened.

     *

     * Note: Used by xml element handler as callback.

     *

     * @author Kilian Singer

     * @param resource $parser The XML parser resource.

     * @param string $name The XML source to parse.

     * @param array $attrs Stores attributes of XML tag.

     */

    private function startelement($parser, $name, $attrs) {

        $current = &$this->current;

        $level = &$this->level;

        if (!empty($name)) {

            if ($level == 0) {

                $current[$level][$name] = array();

                $current[$level][$name]["@"] = $attrs; // Attribute.

                $current[$level][$name]["#"] = array(); // Other tags.

                $current[$level + 1] = & $current[$level][$name]["#"];

                $level++;

            } else {

                if (empty($current[$level][$name])) {

                    $current[$level][$name] = array();

                }

                $siz = count($current[$level][$name]);

                if (!empty($attrs)) {

                    $current[$level][$name][$siz]["@"] = $attrs; // Attribute.

                }

                $current[$level][$name][$siz]["#"] = array(); // Other tags.

                $current[$level + 1] = & $current[$level][$name][$siz]["#"];

                $level++;

            }

        }

    }

    /**

     * Is called when tags are closed.

     *

     * Note: Used by xml element handler as callback.

     *

     * @author Kilian Singer

     * @param resource $parser The XML parser resource.

     * @param string $name The XML source to parse.

     */

    private function endelement($parser, $name) {

        $current = &$this->current;

        $level = &$this->level;

        if (!empty($name)) {

            if (empty($current[$level])) {

                $current[$level] = '';

            } else if (array_key_exists(0, $current[$level])) {

                if (count($current[$level]) == 1) {

                    $current[$level] = $current[$level][0]; // We remove array index if we only have a single entry.

                }

            }

            $level--;

        }

    }

    /**

     * Is called for text between the start and the end of tags.

     *

     * Note: Used by xml element handler as callback.

     *

     * @author Kilian Singer

     * @param resource $parser The XML parser resource.

     * @param string $data The XML source to parse.

     */

    private function characterdata($parser, $data) {

        $current = &$this->current;

        $level = &$this->level;

        if (($data == "0") || (!empty($data) && trim($data) != "")) {

            $siz = count($current[$level]);

            if ($siz == 0) {

                $current[$level][0] = $data;

            } else {

                $key = max(array_keys($current[$level]));

                if (is_int($key)) {

                    end($current[$level]);

                    if (is_int(key($current[$level]))) { // If last index is nummeric we have CDATA and concat.

                        $current[$level][$key] = $current[$level][$key] . $data;

                    } else {

                        $current[$level][$key + 1] = $data; // Otherwise we make a new key.

                    }

                } else {

                    $current[$level][0] = $data;

                }

            }

        }

    }

    /**

     * Parses XML string.

     *

     * Note: Interface is kept equal to previous version.

     *

     * @author Kilian Singer

     * @param string $data the XML source to parse.

     * @param int $whitespace If set to 1 allows the parser to skip "space" characters in xml document. Default is 1

     * @param string $encoding Specify an OUTPUT encoding. If not specified, it defaults to UTF-8.

     * @param bool $reporterrors if set to true, then a {@link xml_format_exception}

     *      exception will be thrown if the XML is not well-formed. Otherwise errors are ignored.

     * @return array|false representation of the parsed XML.

     */

    public function parse($data, $whitespace = 1, $encoding = 'UTF-8', $reporterrors = false) {

        $data = trim($data);

        $this->xml = array();

        $this->current = array();

        $this->level = 0;

        $this->current[0] = & $this->xml;

        $parser = xml_parser_create($encoding);

        xml_parser_set_option($parser, XML_OPTION_CASE_FOLDING, 0);

        xml_parser_set_option($parser, XML_OPTION_SKIP_WHITE, $whitespace);

        xml_set_element_handler($parser, [$this, "startelement"], [$this, "endelement"]);

        xml_set_character_data_handler($parser, [$this, "characterdata"]);

        // Start parsing an xml document.

        for ($i = 0; $i < strlen($data); $i += 4096) {

            if (!xml_parse($parser, substr($data, $i, 4096))) {

                break;

            }

        }

        if ($reporterrors) {

            $errorcode = xml_get_error_code($parser);

            if ($errorcode) {

                $exception = new xml_format_exception(xml_error_string($errorcode),

                        xml_get_current_line_number($parser),

                        xml_get_current_column_number($parser));

                xml_parser_free($parser);

                throw $exception;

            }

        }

        xml_parser_free($parser); // Deletes the parser.

        if (empty($this->xml)) { // XML file is invalid or empty, return false.

            return false;

        }

        return $this->xml;

    }

}

/**

 * XML parsing function calles into class.

 *

 * Note: Used by xml element handler as callback.

 *

 * @param string $data the XML source to parse.

 * @param int $whitespace If set to 1 allows the parser to skip "space" characters in xml document. Default is 1

 * @param string $encoding Specify an OUTPUT encoding. If not specified, it defaults to UTF-8.

 * @param bool $reporterrors if set to true, then a {@link xml_format_exception}

 *      exception will be thrown if the XML is not well-formed. Otherwise errors are ignored.

 * @return array representation of the parsed XML.

 */

function xmlize($data, $whitespace = 1, $encoding = 'UTF-8', $reporterrors = false) {

    $hxml = new core_xml_parser();

    return $hxml->parse($data, $whitespace, $encoding, $reporterrors);

}