<?php /** * Project: MagpieRSS: a simple RSS integration tool * File: rss_parse.inc - parse an RSS or Atom feed * return as a simple object. * * Handles RSS 0.9x, RSS 2.0, RSS 1.0, and Atom 0.3 * * The lastest version of MagpieRSS can be obtained from: * http://magpierss.sourceforge.net * * For questions, help, comments, discussion, etc., please join the * Magpie mailing list: * magpierss-general@lists.sourceforge.net * * @author Kellan Elliott-McCrea <kellan@protest.net> * @version 0.7a * @license GPL * */ define('RSS', 'RSS'); define('ATOM', 'Atom'); require_once (MAGPIE_DIR . 'rss_utils.inc'); /** * Hybrid parser, and object, takes RSS as a string and returns a simple object. * * see: rss_fetch.inc for a simpler interface with integrated caching support * */ class MagpieRSS { var $parser; var $current_item = array(); // item currently being parsed var $items = array(); // collection of parsed items var $channel = array(); // hash of channel fields var $textinput = array(); var $image = array(); var $feed_type; var $feed_version; var $encoding = ''; // output encoding of parsed rss var $_source_encoding = ''; // only set if we have to parse xml prolog var $ERROR = ""; var $WARNING = ""; // define some constants var $_CONTENT_CONSTRUCTS = array('content', 'summary', 'info', 'title', 'tagline', 'copyright'); var $_KNOWN_ENCODINGS = array('UTF-8', 'US-ASCII', 'ISO-8859-1'); // parser variables, useless if you're not a parser, treat as private var $stack = array(); // parser stack var $inchannel = false; var $initem = false; var $incontent = false; // if in Atom <content mode="xml"> field var $intextinput = false; var $inimage = false; var $current_field = ''; var $current_namespace = false; /** * Set up XML parser, parse source, and return populated RSS object.. * * @param string $source string containing the RSS to be parsed * * NOTE: Probably a good idea to leave the encoding options alone unless * you know what you're doing as PHP's character set support is * a little weird. * * NOTE: A lot of this is unnecessary but harmless with PHP5 * * * @param string $output_encoding output the parsed RSS in this character * set defaults to ISO-8859-1 as this is PHP's * default. * * NOTE: might be changed to UTF-8 in future * versions. * * @param string $input_encoding the character set of the incoming RSS source. * Leave blank and Magpie will try to figure it * out. * * * @param bool $detect_encoding if false Magpie won't attempt to detect * source encoding. (caveat emptor) * */ function MagpieRSS ($source, $output_encoding='ISO-8859-1', $input_encoding=null, $detect_encoding=true) { # if PHP xml isn't compiled in, die # if (!function_exists('xml_parser_create')) { $this->error( "Failed to load PHP's XML Extension. " . "http://www.php.net/manual/en/ref.xml.php", E_USER_ERROR ); } list($parser, $source) = $this->create_parser($source, $output_encoding, $input_encoding, $detect_encoding); if (!is_resource($parser)) { $this->error( "Failed to create an instance of PHP's XML parser. " . "http://www.php.net/manual/en/ref.xml.php", E_USER_ERROR ); } $this->parser = $parser; # pass in parser, and a reference to this object # setup handlers # xml_set_object( $this->parser, $this ); xml_set_element_handler($this->parser, 'feed_start_element', 'feed_end_element' ); xml_set_character_data_handler( $this->parser, 'feed_cdata' ); $status = xml_parse( $this->parser, $source ); if (! $status ) { $errorcode = xml_get_error_code( $this->parser ); if ( $errorcode != XML_ERROR_NONE ) { $xml_error = xml_error_string( $errorcode ); $error_line = xml_get_current_line_number($this->parser); $error_col = xml_get_current_column_number($this->parser); $errormsg = "$xml_error at line $error_line, column $error_col"; $this->error( $errormsg ); } } xml_parser_free( $this->parser ); $this->normalize(); } function feed_start_element($p, $element, &$attrs) { $el = $element = strtolower($element); $attrs = array_change_key_case($attrs, CASE_LOWER); // check for a namespace, and split if found $ns = false; if ( strpos( $element, ':' ) ) { list($ns, $el) = split( ':', $element, 2); } if ( $ns and $ns != 'rdf' ) { $this->current_namespace = $ns; } # if feed type isn't set, then this is first element of feed # identify feed from root element # if (!isset($this->feed_type) ) { if ( $el == 'rdf' ) { $this->feed_type = RSS; $this->feed_version = '1.0'; } elseif ( $el == 'rss' ) { $this->feed_type = RSS; $this->feed_version = $attrs['version']; } elseif ( $el == 'feed' ) { $this->feed_type = ATOM; $this->feed_version = $attrs['version']; $this->inchannel = true; } return; } if ( $el == 'channel' ) { $this->inchannel = true; } elseif ($el == 'item' or $el == 'entry' ) { $this->initem = true; if ( isset($attrs['rdf:about']) ) { $this->current_item['about'] = $attrs['rdf:about']; } } // if we're in the default namespace of an RSS feed, // record textinput or image fields elseif ( $this->feed_type == RSS and $this->current_namespace == '' and $el == 'textinput' ) { $this->intextinput = true; } elseif ( $this->feed_type == RSS and $this->current_namespace == '' and $el == 'image' ) { $this->inimage = true; } # handle atom content constructs elseif ( $this->feed_type == ATOM and in_array($el, $this->_CONTENT_CONSTRUCTS) ) { // avoid clashing w/ RSS mod_content if ($el == 'content' ) { $el = 'atom_content'; } $this->incontent = $el; } // if inside an Atom content construct (e.g. content or summary) field treat tags as text elseif ($this->feed_type == ATOM and $this->incontent ) { // if tags are inlined, then flatten $attrs_str = join(' ', array_map('map_attrs', array_keys($attrs), array_values($attrs) ) ); $this->append_content( "<$element $attrs_str>" ); array_unshift( $this->stack, $el ); } // Atom support many links per containging element. // Magpie treats link elements of type rel='alternate' // as being equivalent to RSS's simple link element. // elseif ($this->feed_type == ATOM and $el == 'link' ) { if ( isset($attrs['rel']) and $attrs['rel'] == 'alternate' ) { $link_el = 'link'; } else { $link_el = 'link_' . $attrs['rel']; } $this->append($link_el, $attrs['href']); } // set stack[0] to current element else { array_unshift($this->stack, $el); } } function feed_cdata ($p, $text) { if ($this->feed_type == ATOM and $this->incontent) { $this->append_content( $text ); } else { $current_el = join('_', array_reverse($this->stack)); $this->append($current_el, $text); } } function feed_end_element ($p, $el) { $el = strtolower($el); if ( $el == 'item' or $el == 'entry' ) { $this->items[] = $this->current_item; $this->current_item = array(); $this->initem = false; } elseif ($this->feed_type == RSS and $this->current_namespace == '' and $el == 'textinput' ) { $this->intextinput = false; } elseif ($this->feed_type == RSS and $this->current_namespace == '' and $el == 'image' ) { $this->inimage = false; } elseif ($this->feed_type == ATOM and in_array($el, $this->_CONTENT_CONSTRUCTS) ) { $this->incontent = false; } elseif ($el == 'channel' or $el == 'feed' ) { $this->inchannel = false; } elseif ($this->feed_type == ATOM and $this->incontent ) { // balance tags properly // note: i don't think this is actually neccessary if ( $this->stack[0] == $el ) { $this->append_content("</$el>"); } else { $this->append_content("<$el />"); } array_shift( $this->stack ); } else { array_shift( $this->stack ); } $this->current_namespace = false; } function concat (&$str1, $str2="") { if (!isset($str1) ) { $str1=""; } $str1 .= $str2; } function append_content($text) { if ( $this->initem ) { $this->concat( $this->current_item[ $this->incontent ], $text ); } elseif ( $this->inchannel ) { $this->concat( $this->channel[ $this->incontent ], $text ); } } // smart append - field and namespace aware function append($el, $text) { if (!$el) { return; } if ( $this->current_namespace ) { if ( $this->initem ) { $this->concat( $this->current_item[ $this->current_namespace ][ $el ], $text); } elseif ($this->inchannel) { $this->concat( $this->channel[ $this->current_namespace][ $el ], $text ); } elseif ($this->intextinput) { $this->concat( $this->textinput[ $this->current_namespace][ $el ], $text ); } elseif ($this->inimage) { $this->concat( $this->image[ $this->current_namespace ][ $el ], $text ); } } else { if ( $this->initem ) { $this->concat( $this->current_item[ $el ], $text); } elseif ($this->intextinput) { $this->concat( $this->textinput[ $el ], $text ); } elseif ($this->inimage) { $this->concat( $this->image[ $el ], $text ); } elseif ($this->inchannel) { $this->concat( $this->channel[ $el ], $text ); } } } function normalize () { // if atom populate rss fields if ( $this->is_atom() ) { $this->channel['description'] = $this->channel['tagline']; for ( $i = 0; $i < count($this->items); $i++) { $item = $this->items[$i]; if ( isset($item['summary']) ) $item['description'] = $item['summary']; if ( isset($item['atom_content'])) $item['content']['encoded'] = $item['atom_content']; $atom_date = (isset($item['issued']) ) ? $item['issued'] : $item['modified']; if ( $atom_date ) { $epoch = @parse_w3cdtf($item['modified']); if ($epoch and $epoch > 0) { $item['date_timestamp'] = $epoch; } } $this->items[$i] = $item; } } elseif ( $this->is_rss() ) { $this->channel['tagline'] = $this->channel['description']; for ( $i = 0; $i < count($this->items); $i++) { $item = $this->items[$i]; if ( isset($item['description'])) $item['summary'] = $item['description']; if ( isset($item['content']['encoded'] ) ) $item['atom_content'] = $item['content']['encoded']; if ( $this->is_rss() == '1.0' and isset($item['dc']['date']) ) { $epoch = @parse_w3cdtf($item['dc']['date']); if ($epoch and $epoch > 0) { $item['date_timestamp'] = $epoch; } } elseif ( isset($item['pubdate']) ) { $epoch = @strtotime($item['pubdate']); if ($epoch > 0) { $item['date_timestamp'] = $epoch; } } $this->items[$i] = $item; } } } function is_rss () { if ( $this->feed_type == RSS ) { return $this->feed_version; } else { return false; } } function is_atom() { if ( $this->feed_type == ATOM ) { return $this->feed_version; } else { return false; } } /** * return XML parser, and possibly re-encoded source * */ function create_parser($source, $out_enc, $in_enc, $detect) { if ( substr(phpversion(),0,1) == 5) { $parser = $this->php5_create_parser($in_enc, $detect); } else { list($parser, $source) = $this->php4_create_parser($source, $in_enc, $detect); } if ($out_enc) { $this->encoding = $out_enc; xml_parser_set_option($parser, XML_OPTION_TARGET_ENCODING, $out_enc); } return array($parser, $source); } /** * Instantiate an XML parser under PHP5 * * PHP5 will do a fine job of detecting input encoding * if passed an empty string as the encoding. * * All hail libxml2! * */ function php5_create_parser($in_enc, $detect) { // by default php5 does a fine job of detecting input encodings if(!$detect && $in_enc) { return xml_parser_create($in_enc); } else { return xml_parser_create(''); } } /** * Instaniate an XML parser under PHP4 * * Unfortunately PHP4's support for character encodings * and especially XML and character encodings sucks. As * long as the documents you parse only contain characters * from the ISO-8859-1 character set (a superset of ASCII, * and a subset of UTF-8) you're fine. However once you * step out of that comfy little world things get mad, bad, * and dangerous to know. * * The following code is based on SJM's work with FoF * @see http://minutillo.com/steve/weblog/2004/6/17/php-xml-and-character-encodings-a-tale-of-sadness-rage-and-data-loss * */ function php4_create_parser($source, $in_enc, $detect) { if ( !$detect ) { return array(xml_parser_create($in_enc), $source); } if (!$in_enc) { if (preg_match('/<?xml.*encoding=[\'"](.*?)[\'"].*?>/m', $source, $m)) { $in_enc = strtoupper($m[1]); $this->source_encoding = $in_enc; } else { $in_enc = 'UTF-8'; } } if ($this->known_encoding($in_enc)) { return array(xml_parser_create($in_enc), $source); } // the dectected encoding is not one of the simple encodings PHP knows // attempt to use the iconv extension to // cast the XML to a known encoding // @see http://php.net/iconv if (function_exists('iconv')) { $encoded_source = iconv($in_enc,'UTF-8', $source); if ($encoded_source) { return array(xml_parser_create('UTF-8'), $encoded_source); } } // iconv didn't work, try mb_convert_encoding // @see http://php.net/mbstring if(function_exists('mb_convert_encoding')) { $encoded_source = mb_convert_encoding($source, 'UTF-8', $in_enc ); if ($encoded_source) { return array(xml_parser_create('UTF-8'), $encoded_source); } } // else $this->error("Feed is in an unsupported character encoding. ($in_enc) " . "You may see strange artifacts, and mangled characters.", E_USER_NOTICE); return array(xml_parser_create(), $source); } function known_encoding($enc) { $enc = strtoupper($enc); if ( in_array($enc, $this->_KNOWN_ENCODINGS) ) { return $enc; } else { return false; } } function error ($errormsg, $lvl=E_USER_WARNING) { // append PHP's error message if track_errors enabled if ( $php_errormsg ) { $errormsg .= " ($php_errormsg)"; } if ( MAGPIE_DEBUG ) { trigger_error( $errormsg, $lvl); } else { error_log( $errormsg, 0); } $notices = E_USER_NOTICE|E_NOTICE; if ( $lvl&$notices ) { $this->WARNING = $errormsg; } else { $this->ERROR = $errormsg; } } } // end class RSS function map_attrs($k, $v) { return "$k=\"$v\""; } ?>