JavaScript RSS Parser

[code]/*
** Javascript RSS parser
**
** copyright (c) Stas Verberkt (Legolas), 2001 - 2006
** Released under the GNU General Public License
**
** WWW: http://www.legolasweb.nl/
** E-mail: [email protected]
**
** Using:
** Include this JS file in your page
** Make sure there's a div with id="rss"
** To change the feed edit the feed var at the bottom
** default it uses the query string
** (it prepends the query string with get.php?,
** because it isn't allowed to open extern sites using xmlHTTPRequest.
** get.php is a php file which servers the page.)
*/

/* Functions */
function init() {
	if (!feed) {
		var goal = document.getElementById('rss');
		goal.innerHTML = 'No feed specified';
	}
	else {
		getFeed();
	}
}

function createHTTPHandler() {
	var httphandler = false;
	/*@cc_on @*/
	/*@if (@_jscript_version >= 5)
		// JScript gives us Conditional compilation, we can cope with old IE versions.
		// and security blocked creation of the objects.
		try {
			httphandler = new ActiveXObject("Msxml2.XMLHTTP");
		}
		catch (e) {
			try {
				httphandler = new ActiveXObject("Microsoft.XMLHTTP");
			}
			catch (E) {
				httphandler = false;
			}
		}
	@end @*/
	if (!httphandler && typeof XMLHttpRequest != 'undefined') {
		httphandler = new XMLHttpRequest();
	}
	return httphandler;
}

function getFeed() {
	xmlhttprequest.open('GET', feed, true);
	xmlhttprequest.onreadystatechange = parseFeed;
	xmlhttprequest.send(null);
}

function parseFeed() {
	if (xmlhttprequest.readyState == 4) {
		var error = null;
		if (xmlhttprequest.responseXML) {
			if (xmlhttprequest.responseXML.documentElement) {
				if (xmlhttprequest.responseXML.documentElement.tagName == 'parsererror') {
					error = 'Error parsing XML response:<br /> ' + xmlhttprequest.responseXML.documentElement.firstChild.nodeValue;
				}
				else if (xmlhttprequest.responseXML.documentElement.tagName == 'error') {
					error = 'Error retrieving XML response:<br /> ' + xmlhttprequest.responseXML.documentElement.firstChild.nodeValue;
				}
			}
			else {
				if (xmlhttprequest.responseXML.parseError) {
					error = 'Error parsing XML response:<br /> ' + xmlhttprequest.responseXML.parseError.reason + ' (' + url + ')';
				}
				else {
					error = 'No valid data in XML response';
				}
			}
		}
		else {
			error = 'The responseXML object was empty';
		}
		var goal = document.getElementById('rss');
		if (!error) {
			var rss = xmlhttprequest.responseXML;
			goal.innerHTML = null;
			parseRSS(rss, goal);
		}
		else {
			goal.innerHTML = error;
		}
	}
}

function parseRSS(rss, goal) {
	var roots = rss.getElementsByTagName('channel');
	for (var i = 0; i < roots.length; i++) {
		var rssdiv = document.createElement('div');
		goal.appendChild(rssdiv);
		rssdiv.setAttribute('id', 'rss' + i);

		var title = null;
		var link = null;
		var items = new Array();
		var image = new Array();
		var index = 0;

		for (var j = 0; j < roots[i].childNodes.length; j++) {
			if (roots[i].childNodes[j].tagName == 'title') {
				title = roots[i].childNodes[j].firstChild.nodeValue;
			}
			else if (roots[i].childNodes[j].tagName == 'link') {
				link = roots[i].childNodes[j].firstChild.nodeValue;
			}
			else if (roots[i].childNodes[j].tagName == 'image') {
				image = parseElement(roots[i].childNodes[j]);
			}
			else if (roots[i].childNodes[j].tagName == 'item') {
				items[index] = parseElement(roots[i].childNodes[j]);
				index++;
			}
		}

		var eltitle = document.createElement('h1');
		rssdiv.appendChild(eltitle);
		var ellink = document.createElement('a');
		eltitle.appendChild(ellink);
		ellink.setAttribute('href', link);
		ellink.setAttribute('title', title);
		ellinktitle = document.createTextNode(title);
		ellink.appendChild(ellinktitle);
		var elimgdiv = document.createElement('div');
		rssdiv.appendChild(elimgdiv);
		elimgdiv.setAttribute('id', 'rss' + i + '-image');
		elimgdiv.setAttribute('class', 'rssimage');
		var elimg = document.createElement('img');
		elimgdiv.appendChild(elimg);
		elimg.setAttribute('src', image['url']);
		elimg.setAttribute('alt', image['title']);
		var elitems = document.createElement('div');
		rssdiv.appendChild(elitems);
		elitems.setAttribute('id', 'rss' + i + '-items');
		elitems.setAttribute('class', 'rssitems');

		for (var j = 0; j < items.length; j++) {
			var elitem = document.createElement('div');
			elitems.appendChild(elitem);
			elitem.setAttribute('id', 'rss' + i + '-item' + j);
			elitem.setAttribute('class', 'rssitem');
			var elitemtitle = document.createElement('h2');
			elitem.appendChild(elitemtitle);
			var elitemlink = document.createElement('a');
			elitemtitle.appendChild(elitemlink);
			elitemlink.setAttribute('href', items[j]['link']);
			elitemlink.setAttribute('title', items[j]['title']);
			var elitemlinktitle = document.createTextNode(items[j]['title']);
			elitemlink.appendChild(elitemlinktitle);
			var elitemdate = document.createElement('span');
			elitem.appendChild(elitemdate);
			elitemdate.setAttribute('id', 'rss' + i + '-item' + j + '-date');
			elitemdate.setAttribute('class', 'rssitemdate');
			var elitemdatetext = document.createTextNode(items[j]['pubDate']);
			elitemdate.appendChild(elitemdatetext);
			var elitemtext = document.createElement('p');
			elitem.appendChild(elitemtext);
			elitemtext.setAttribute('id', 'rss' + i + '-item' + j + '-content');
			elitemtext.setAttribute('class', 'rssitemcontent');
			var elitemtexttext = document.createTextNode(items[j]['description']);
			elitemtext.appendChild(elitemtexttext);
		}
	}
}

function parseElement(root) {
	var element = new Array();
	for (var i = 0; i < root.childNodes.length; i++) {
		if (root.childNodes[i].tagName) {
			element[root.childNodes[i].tagName] = root.childNodes[i].firstChild.nodeValue;
		}
	}

	return element;
}



/* Onload */
var feed = 'get.php?' + window.location.search.substr(1);
var xmlhttprequest = createHTTPHandler();
window.onload = init;[/code]