/*
* Copyright 2006-2008 Sxip Identity Corporation
*/
package org.openid4java.discovery.html;
import java.util.Arrays;
import java.util.List;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.apache.html.dom.HTMLDocumentImpl;
import org.openid4java.OpenIDException;
import org.openid4java.util.OpenID4JavaDOMParser;
import org.openid4java.discovery.DiscoveryException;
import org.openid4java.discovery.html.HtmlParser;
import org.openid4java.discovery.html.HtmlResult;
import org.w3c.dom.NodeList;
import org.w3c.dom.html.HTMLHeadElement;
import org.w3c.dom.html.HTMLLinkElement;
/**
* A {@link HtmlParser} implementation using the DOMParser of CyberNeko HTML.
*
* @author Sutra Zhou
* @since 0.9.4
* @see org.openid4java.util.OpenID4JavaDOMParser
*/
public class CyberNekoDOMHtmlParser implements HtmlParser
{
private static final Log _log = LogFactory.getLog(CyberNekoDOMHtmlParser.class);
private static final boolean DEBUG = _log.isDebugEnabled();
/*
* (non-Javadoc)
*
* @see org.openid4java.discovery.html.HtmlParser#parse(java.lang.String,
* org.openid4java.discovery.html.HtmlResult)
*/
public void parseHtml(String htmlData, HtmlResult result)
throws DiscoveryException
{
if (DEBUG)
_log.debug("Parsing HTML data:\n" + htmlData);
HTMLDocumentImpl doc = this.parseDocument(htmlData);
NodeList heads = doc.getElementsByTagName("head");
if (heads.getLength() != 1)
throw new DiscoveryException(
"HTML response must have exactly one HEAD element, "
+ "found " + heads.getLength() + " : "
+ heads.toString(),
OpenIDException.DISCOVERY_HTML_PARSE_ERROR);
HTMLHeadElement head = (HTMLHeadElement) doc.getHead();
NodeList linkElements = head.getElementsByTagName("LINK");
for (int i = 0, len = linkElements.getLength(); i < len; i++)
{
HTMLLinkElement linkElement = (HTMLLinkElement) linkElements.item(i);
setResult(linkElement.getRel(), linkElement.getHref(), result);
}
if (DEBUG)
_log.debug("HTML discovery result:\n" + result);
}
private HTMLDocumentImpl parseDocument(String htmlData) throws DiscoveryException
{
OpenID4JavaDOMParser parser = new OpenID4JavaDOMParser();
try
{
parser.parse(OpenID4JavaDOMParser.createInputSource(htmlData));
}
catch (Exception e)
{
throw new DiscoveryException("Error parsing HTML message",
OpenIDException.DISCOVERY_HTML_PARSE_ERROR, e);
}
if (parser.isIgnoredHeadStartElement())
{
throw new DiscoveryException(
"HTML response must have exactly one HEAD element.",
OpenIDException.DISCOVERY_HTML_PARSE_ERROR);
}
return (HTMLDocumentImpl) parser.getDocument();
}
/**
* Set the result from <code>rel</code> and <code>href</code> that
* parsed from node <code>link</code>.
*
* @param rel
* the <code>rel</code>
* @param href
* the <code>href</code>
* @param result
* the result to set
* @throws DiscoveryException
* if the value has been setted yet, that is to say, find more
* than one entries with the same name(attribute value of
* <code>rel</code>).
*/
private void setResult(String rel, String href, HtmlResult result)
throws DiscoveryException
{
List relations = Arrays.asList(rel.split(" "));
// openid.server
if (relations.contains("openid.server"))
{
if (result.getOP1Endpoint() != null)
throw new DiscoveryException(
"More than one openid.server entries found",
OpenIDException.DISCOVERY_HTML_PARSE_ERROR);
if (DEBUG)
_log.debug("Found OpenID1 endpoint: " + href);
result.setEndpoint1(href);
}
// openid.delegate
if (relations.contains("openid.delegate"))
{
if (result.getDelegate1() != null)
throw new DiscoveryException(
"More than one openid.delegate entries found",
OpenIDException.DISCOVERY_HTML_PARSE_ERROR);
if (DEBUG)
_log.debug("Found OpenID1 delegate: " + href);
result.setDelegate1(href);
}
// openid2.provider
if (relations.contains("openid2.provider"))
{
if (result.getOP2Endpoint() != null)
throw new DiscoveryException(
"More than one openid.server entries found",
OpenIDException.DISCOVERY_HTML_PARSE_ERROR);
if (DEBUG)
_log.debug("Found OpenID2 endpoint: " + href);
result.setEndpoint2(href);
}
// openid2.local_id
if (relations.contains("openid2.local_id"))
{
if (result.getDelegate2() != null)
throw new DiscoveryException(
"More than one openid2.local_id entries found",
OpenIDException.DISCOVERY_HTML_PARSE_ERROR);
if (DEBUG)
_log.debug("Found OpenID2 localID: " + href);
result.setDelegate2(href);
}
}
}