/*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You under the Apache License, Version 2.0
* (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.apache.cocoon.portal.transformation;
import java.io.IOException;
import java.net.MalformedURLException;
import java.util.Map;
import java.util.Stack;
import org.apache.avalon.framework.parameters.Parameters;
import org.apache.avalon.framework.service.ServiceException;
import org.apache.avalon.framework.service.ServiceManager;
import org.apache.avalon.framework.service.Serviceable;
import org.apache.cocoon.ProcessingException;
import org.apache.cocoon.environment.ObjectModelHelper;
import org.apache.cocoon.environment.SourceResolver;
import org.apache.cocoon.portal.Constants;
import org.apache.cocoon.portal.coplet.CopletInstanceData;
import org.apache.cocoon.transformation.AbstractTransformer;
import org.apache.cocoon.xml.AttributesImpl;
import org.xml.sax.Attributes;
import org.xml.sax.SAXException;
/**
* This Transformer deals with tags containing links to external applications that need to be converted so
* that not the external application will be called directly but the request gets routed via the cocoon portal
* (either via proxy transformer or proxy reader).
* The link transformer therefore cooperates with the event link transformer.
* Tags that include a link for which a link event needs to be generated will be converted to
* <eventlink> elements.
* Examples:<br><br>
*
* <pre>
* <img src="images/logo.jpg"> will be converted to use the proxy reader:
* <img src="proxy-images/logo.jpg&cocoon-portal-copletid=xxx&cocoon-portal-portalname=yyy
* <br>
* <form action="/submitted.jsp"> will be converted to be processed by the event link transformer
* <eventlink action="/submitted.jsp" attribute="action" element="form">
* </pre>
*
* @author <a href="mailto:gernot.koller@rizit.at">Gernot Koller</a>
* @author <a href="mailto:friedrich.klenner@rzb.at">Friedrich Klenner</a>
*
* @version CVS $Id$
*/
public class LinkTransformer
extends AbstractTransformer
implements Serviceable {
/**
* Namespace prefix usef vor NewEventLinkTransformer-Namespace
*/
public static final String NAMESPACE_PREFIX = "ev";
/**
* Used for appending a request parameter containing the coplet id
*/
protected String copletIdParamString;
/**
* Used for appending a request parameter containing the portal name
*/
protected String portalNameParamString;
/**
* The coplet instance data
*/
protected CopletInstanceData copletInstanceData;
/**
* The html document base uri
*/
protected String documentBase;
/**
* Used to store elements' name between startTransformingElement and endTransformingElement.
*/
protected Stack elementStack = new Stack();
/**
* The avalon service manager
*/
protected ServiceManager manager;
/* (non-Javadoc)
* @see org.apache.avalon.framework.service.Serviceable#service(org.apache.avalon.framework.service.ServiceManager)
*/
public void service(ServiceManager manager) throws ServiceException {
this.manager = manager;
}
/** The prefix */
protected String prefix;
/** Handle target self as no target? */
protected boolean ignoreTargetSelf;
/**
* @see AbstractTransformer#setup(SourceResolver, Map, String, Parameters)
*/
public void setup(SourceResolver resolver,
Map objectModel,
String src,
Parameters par)
throws ProcessingException, SAXException, IOException {
this.ignoreTargetSelf = par.getParameterAsBoolean("ignore-target-self", false);
this.copletInstanceData =
ProxyTransformer.getInstanceData(
this.manager,
objectModel,
par);
this.copletIdParamString =
ProxyTransformer.COPLETID + "=" + copletInstanceData.getId();
Map context = (Map) objectModel.get(ObjectModelHelper.PARENT_CONTEXT);
this.portalNameParamString =
ProxyTransformer.PORTALNAME
+ "="
+ (String) context.get(Constants.PORTAL_NAME_KEY);
this.prefix = par.getParameter("prefix", ProxyTransformer.PROXY_PREFIX);
}
/**
* Recycle this component.
* All instance variables are set to <code>null</code>.
*/
public void recycle() {
super.recycle();
this.copletInstanceData = null;
this.elementStack.clear();
this.copletIdParamString = null;
this.portalNameParamString = null;
}
/**
* @see org.xml.sax.ContentHandler#startDocument()
*/
public void startDocument() throws SAXException {
super.startDocument();
documentBase =
(String)copletInstanceData.getAttribute(ProxyTransformer.DOCUMENT_BASE);
super.startPrefixMapping(NAMESPACE_PREFIX,
NewEventLinkTransformer.NAMESPACE_URI);
}
/**
* @see org.xml.sax.ContentHandler#endDocument()
*/
public void endDocument() throws SAXException {
super.endPrefixMapping(NAMESPACE_PREFIX);
super.endDocument();
}
/**
* @see org.xml.sax.ContentHandler#startElement(String, String, String, Attributes)
*/
public void startElement(String uri, String name, String raw,
Attributes attributes)
throws SAXException {
if ("form".equalsIgnoreCase(name)) {
handleTag(
"action",
uri,
name,
raw,
attributes,
true,
(attributes.getIndex("target") > -1));
} else if ("script".equalsIgnoreCase(name)) {
handleTag("src", uri, name, raw, attributes, false, false);
} else if ("img".equalsIgnoreCase(name)) {
handleTag("src", uri, name, raw, attributes, false, false);
} else if ("link".equalsIgnoreCase(name)) {
handleTag("href", uri, name, raw, attributes, false, false);
} else if ("a".equalsIgnoreCase(name)) {
boolean direct;
final String v = attributes.getValue("target");
if ( v == null || (this.ignoreTargetSelf && v.equals("self")) ) {
direct = false;
} else {
direct = true;
}
handleTag("href", uri, name, raw, attributes, true, direct);
} else if ("menu-item".equalsIgnoreCase(name)) {
handleTag("href", uri, name, raw, attributes, true, false);
} else if ("input".equalsIgnoreCase(name)) {
handleTag("src", uri, name, raw, attributes, false, false);
} else if ("applet".equalsIgnoreCase(name)) {
if (attributes.getIndex("codebase") > -1) {
handleTag("codebase", uri, name, raw, attributes, false, true);
}
} else {
super.startElement(uri, name, raw, attributes);
}
}
/**
* @see org.xml.sax.ContentHandler#endElement(String, String, String)
*/
public void endElement(String uri, String name, String raw)
throws SAXException {
String elementName = null;
if (!elementStack.empty()) {
elementName = (String) elementStack.peek();
}
if (elementName != null && elementName.equals(name)) {
elementStack.pop();
super.endElement(
NewEventLinkTransformer.NAMESPACE_URI,
NewEventLinkTransformer.EVENT_ELEM,
NAMESPACE_PREFIX + ":" + NewEventLinkTransformer.EVENT_ELEM);
} else {
super.endElement(uri, name, raw);
}
}
/**
* The handleTag method is responsible for preparing tags so that they can either be conveted to
* link events by the event link transformer or that the proxy reader is called directly.
* Tags with absolute links (starting with "http://", "ftp://", etc.) will not be touched.
* Tags which contain a target attribute will be modified to call the uri directly
* (no proxy reader or proxy transformer involved).
* Tags (like <a href="uri"&ht; or <form action="uri">, etc.) that require a link event will be converted to
* <eventlink> elements, so that the event link transformer can create the necessary link event
* and the proxy transformer will be used.
* Tags (like <img src="uri">) that shoud call the proxy reader will be converted to do so.
*
* Examples:<br><br>
*
* <pre>
* <a href="http://www.somewhere.com"> will not be converted because of absolute url
* <br>
* <img src="images/logo.jpg"> will be converted to use the proxy reader:
* <img src="proxy-images/logo.jpg&cocoon-portal-copletid=xxx&cocoon-portal-portalname=yyy
* <br>
* <form action="/submitted.jsp"> will be converted to use proxy transformer:
* <eventlink action="/submitted.jsp" attribute="action" element="form">
* </pre>
*
* @param attributeName Name oft the attribute containing the link to be converted
* @param uri Namespace URI
* @param elementName Name of the element (tag)
* @param raw Raw name of the element (including namespace prefix)
* @param attributes Attributes of the element
* @param eventLink True signals that the tag sould be converted to an event link tag.
* @param direct True signals that the uri should point directly to the external resource (no proxys)
* @throws SAXException if an invalid URL was detected.
*/
public void handleTag(String attributeName,
String uri,
String elementName,
String raw,
Attributes attributes,
boolean eventLink,
boolean direct)
throws SAXException {
String remoteURI = attributes.getValue(attributeName);
if ((remoteURI == null)
|| remoteURI.startsWith("http://")
|| remoteURI.startsWith("https://")
|| remoteURI.startsWith("#")
|| remoteURI.startsWith("ftp://")
|| remoteURI.startsWith("javascript:")
|| remoteURI.startsWith("mailto:")) {
super.startElement(uri, elementName, raw, attributes);
} else {
boolean evalTarget;
final String v = attributes.getValue("target");
if ( v == null || (this.ignoreTargetSelf && v.equals("self")) ) {
evalTarget = false;
} else {
evalTarget = true;
}
if (evalTarget || direct) {
try {
remoteURI =
ProxyTransformer.resolveURI(remoteURI, documentBase);
eventLink = false;
} catch (MalformedURLException ex) {
throw new SAXException(
"Invalid URL encountered: " + remoteURI,
ex);
}
} else {
remoteURI = this.buildUrlString(remoteURI, !eventLink);
}
Attributes newAttributes =
modifyLinkAttribute(attributeName, remoteURI, attributes);
if (eventLink) {
this.startEventLinkElement(
elementName,
attributeName,
newAttributes);
} else {
super.startElement(uri, elementName, raw, newAttributes);
}
}
}
/**
* Replaces the link of given attribute whith the new uri.
* @param attribute Name of the attribute containing the link
* @param remoteURI The new uri
* @param attributes List of attributes
* @return The modified List of attributes
*/
protected Attributes modifyLinkAttribute(String attribute,
String remoteURI,
Attributes attributes) {
AttributesImpl newAttributes = new AttributesImpl(attributes);
int index = newAttributes.getIndex(attribute);
newAttributes.setValue(index, remoteURI);
return newAttributes;
}
/**
* Replaces the given element with an eventlink element adding the attribute and element attribute within
* the SAX stream.
* @param element Original name of the element
* @param attribute Name of the attribute containing the link
* @param attributes Original list of attributes
* @throws SAXException
*/
protected void startEventLinkElement(String element,
String attribute,
Attributes attributes)
throws SAXException {
elementStack.push(element);
AttributesImpl eventAttributes = null;
if (attributes instanceof AttributesImpl) {
eventAttributes = (AttributesImpl) attributes;
} else {
eventAttributes = new AttributesImpl(attributes);
}
eventAttributes.addCDATAAttribute(NewEventLinkTransformer.ATTRIBUTE_ATTR, attribute);
eventAttributes.addCDATAAttribute(NewEventLinkTransformer.ELEMENT_ATTR, element);
eventAttributes.addCDATAAttribute("coplet", this.copletInstanceData.getId());
super.startElement(
NewEventLinkTransformer.NAMESPACE_URI,
NewEventLinkTransformer.EVENT_ELEM,
NAMESPACE_PREFIX + ":" + NewEventLinkTransformer.EVENT_ELEM,
eventAttributes);
}
/**
* Retrieves and stores any session token, appends proxy reader prefix and parameters if necessary
* @param uri the url to be converted
* @param applyPrefixAndPortalParams true signals that the url should be converted to call the proxy-reader
* @return the converted uri
* FIXME: anchors (#) should be treated right!
*/
protected String buildUrlString(String uri,
boolean applyPrefixAndPortalParams) {
StringBuffer uriBuffer = new StringBuffer(uri.length());
int index_semikolon = uri.indexOf(";");
int index_question = uri.indexOf("?");
if ((index_semikolon > -1)) {
String sessionToken =
uri.substring(
index_semikolon + 1,
(index_question == -1 ? uri.length() : index_question));
copletInstanceData.getPersistentAspectData().put(
ProxyTransformer.SESSIONTOKEN,
sessionToken);
}
if (applyPrefixAndPortalParams) {
uriBuffer.append(this.prefix);
}
uriBuffer.append(uri);
if (applyPrefixAndPortalParams) {
uriBuffer.append((index_question == -1 ? '?' : '&'));
uriBuffer.append(this.copletIdParamString);
uriBuffer.append('&');
uriBuffer.append(this.portalNameParamString);
}
return uriBuffer.toString();
}
}