/*
* 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.transformation;
import java.io.IOException;
import java.util.Map;
import java.util.regex.Pattern;
import java.util.regex.PatternSyntaxException;
import org.apache.avalon.framework.configuration.Configurable;
import org.apache.avalon.framework.configuration.Configuration;
import org.apache.avalon.framework.configuration.ConfigurationException;
import org.apache.avalon.framework.parameters.Parameters;
import org.apache.cocoon.ProcessingException;
import org.apache.cocoon.caching.CacheableProcessingComponent;
import org.apache.cocoon.environment.ObjectModelHelper;
import org.apache.cocoon.environment.Request;
import org.apache.cocoon.environment.Response;
import org.apache.cocoon.environment.Session;
import org.apache.cocoon.environment.SourceResolver;
import org.apache.excalibur.source.SourceValidity;
import org.apache.excalibur.source.impl.validity.NOPValidity;
import org.xml.sax.Attributes;
import org.xml.sax.SAXException;
import org.xml.sax.helpers.AttributesImpl;
/**
* @cocoon.sitemap.component.documentation
* The encodeURL transformer emits encoded URLs.
*
* @cocoon.sitemap.component.name encodeurl
* @cocoon.sitemap.component.logger sitemap.transformer.encodeURL
* @cocoon.sitemap.component.documentation.caching
* TBD
*
* @cocoon.sitemap.component.pooling.max 32
*
* The encodeURL transformer emits encoded URLs.
* <p>
* This transformer applies encodeURL method to URLs.
* You may want to use this transform to avoid doing the manually
* encodeURL() calls.
* </p>
* <p>
* Usually this transformer is appended as last transformer before
* the serialization process. In this case it is possible to encode
* URLs introduced in the generator, and xslt transformer phase.
* </p>
* <p>
* You can specify which attributes hold URL values in order to restrict
* URL rewriting to specific attributes only.
* </p>
* <p>
* Usage in a sitemap:
* </p>
* <pre><tt>
* <map:composition>
* ...
* <map:transformers>
* ...
* <map:transformer type="encodeURL"
* src="org.apache.cocoon.optional.transformation.EncodeURLTransformer">
* <exclude-name>img/@src|a/@href=.&asterik;adserver</exclude-name>
* <include-name>.&asterik;/@href|.&asterik;/@src|.&asterik;/@action</include-name>
* </map:transformer>
* ...
* <map:pipelines>
* <map:pipeline>
* ...
* <map:transform type="encodeURL"/>
* ...
* </pre></tt>
*
* @author <a href="mailto:bh22351@i-one.at">Bernhard Huber</a>
* @version CVS $Id: EncodeURLTransformer.java 153376 2005-02-11 08:50:21Z cziegeler $
*/
public class EncodeURLTransformer
extends AbstractTransformer
implements Configurable, CacheableProcessingComponent {
/**
* Configuration name for specifying excluding patterns,
* ie exclude-name.
*/
public final static String EXCLUDE_NAME = "exclude-name";
/**
* Configuration name for specifying including patterns,
* ie include-name.
*/
public final static String INCLUDE_NAME = "include-name";
/**
* Configuration default exclude pattern,
* ie img/@src
*/
public final static String EXCLUDE_NAME_DEFAULT = "img/@src=";
/**
* Configuration default exclude pattern,
* ie .*\/@href|.*\/@action|frame/@src
*/
public final static String INCLUDE_NAME_DEFAULT = ".*/@href=|.*/@action=|frame/@src=";
private String includeNameConfigure = INCLUDE_NAME_DEFAULT;
private String excludeNameConfigure = EXCLUDE_NAME_DEFAULT;
private ElementAttributeMatching elementAttributeMatching;
private Response response;
private boolean isEncodeURLNeeded;
private Session session;
/**
* check if encoding of URLs is neccessary.
*
* This is true if session object exists, and session-id
* was provided from URL, or session is new.
* The result is stored in some instance variables
*/
protected void checkForEncoding(Request request) {
this.session = request.getSession(false);
this.isEncodeURLNeeded = false;
if ( null != this.session ) {
// do encoding if session id is from URL, or the session is new,
// fixes BUG #13855, due to paint007@mc.duke.edu
if ( request.isRequestedSessionIdFromURL() || this.session.isNew()) {
this.isEncodeURLNeeded = true;
}
}
}
/**
* Setup the transformer.
* <p>
* Setup include, and exclude patterns from the parameters
* </p>
*
* @param resolver source resolver
* @param objectModel sitemap objects
* @param parameters request parameters
*
*/
public void setup(SourceResolver resolver, Map objectModel, String source, Parameters parameters)
throws ProcessingException, SAXException, IOException {
this.checkForEncoding(ObjectModelHelper.getRequest(objectModel));
if (this.isEncodeURLNeeded) {
this.response = ObjectModelHelper.getResponse(objectModel);
// don't check if URL encoding is needed now, as
// a generator might create a new session
final String includeName = parameters.getParameter(INCLUDE_NAME,
this.includeNameConfigure);
final String excludeName = parameters.getParameter(EXCLUDE_NAME,
this.excludeNameConfigure);
try {
this.elementAttributeMatching = new ElementAttributeMatching(includeName, excludeName);
} catch (PatternSyntaxException reex) {
final String message = "Cannot parse include-name: " + includeName + " " +
"or exclude-name: " + excludeName + "!";
throw new ProcessingException(message, reex);
}
}
}
/**
* BEGIN SitemapComponent methods
*
* @param configuration Description of Parameter
* @exception ConfigurationException Description of Exception
*/
public void configure(Configuration configuration) throws ConfigurationException {
Configuration child;
child = configuration.getChild(INCLUDE_NAME);
this.includeNameConfigure = child.getValue(INCLUDE_NAME_DEFAULT);
child = configuration.getChild(EXCLUDE_NAME);
this.excludeNameConfigure = child.getValue(EXCLUDE_NAME_DEFAULT);
if (this.includeNameConfigure == null) {
String message = "Configure " + INCLUDE_NAME + "!";
throw new ConfigurationException(message);
}
if (this.excludeNameConfigure == null) {
String message = "Configure " + EXCLUDE_NAME + "!";
throw new ConfigurationException(message);
}
}
/**
* Recycle resources of this transformer
*/
public void recycle() {
super.recycle();
this.response = null;
this.session = null;
this.elementAttributeMatching = null;
}
/**
* Generate the unique key.
* This key must be unique inside the space of this component.
*
* @return The generated key hashes the src
*/
public java.io.Serializable getKey() {
if (this.isEncodeURLNeeded) {
return null;
} else {
return "1";
}
}
/**
* Generate the validity object.
*
* @return The generated validity object or <code>null</code> if the
* component is currently not cacheable.
*/
public SourceValidity getValidity() {
if (this.isEncodeURLNeeded) {
return null;
} else {
return NOPValidity.SHARED_INSTANCE;
}
}
/**
* Start parsing an element
*
* @param uri of the element
* @param name of the element
* @param raw name of the element
* @param attributes list
* @exception SAXException Description of Exception
*/
public void startElement(String uri, String name, String raw, Attributes attributes)
throws SAXException {
if (this.isEncodeURLNeeded && this.elementAttributeMatching != null) {
String lname = name;
if (attributes != null && attributes.getLength() > 0) {
AttributesImpl new_attributes = new AttributesImpl(attributes);
for (int i = 0; i < new_attributes.getLength(); i++) {
String attr_lname = new_attributes.getLocalName(i);
String value = new_attributes.getValue(i);
if (elementAttributeMatching.matchesElementAttribute(lname, attr_lname, value)) {
// don't use simply this.response.encodeURL(value)
// but be more smart about the url encoding
final String new_value = this.encodeURL(value);
if (getLogger().isDebugEnabled()) {
this.getLogger().debug("element/@attribute matches: " + name + "/@" + attr_lname);
this.getLogger().debug("encodeURL: " + value + " -> " + new_value);
}
new_attributes.setValue(i, new_value);
}
}
// parent handles element using encoded attribute values
super.contentHandler.startElement(uri, name, raw, new_attributes);
return;
}
}
// no match, parent handles element as-is
super.contentHandler.startElement(uri, name, raw, attributes);
}
/**
* Do the URL rewriting.
* <p>
* Check if <code>url</code> contains already the sessionid, some servlet-engines
* just appends the session-id without checking if the sessionid is already present.
* </p>
*
* @param url the URL probably without sessionid.
* @return String the original url inclusive the sessionid
*/
private String encodeURL(String url) {
String encoded_url;
if (this.response != null) {
// As some servlet-engine does not check if url has been already rewritten
if (this.session != null && url.indexOf(this.session.getId()) > -1) {
// url contains already the session id encoded
encoded_url = url;
} else {
// do encode the session id
encoded_url = this.response.encodeURL(url);
}
} else {
encoded_url = url;
}
return encoded_url;
}
/**
* A helper class for matching element names, and attribute names.
*
* <p>
* For given include-name, exclude-name decide if element-attribute pair
* matches. This class defines the precedence and matching algorithm.
* </p>
*
* @author <a href="mailto:bh22351@i-one.at">Bernhard Huber</a>
* @version CVS $Id: EncodeURLTransformer.java 153376 2005-02-11 08:50:21Z cziegeler $
*/
public static class ElementAttributeMatching {
/**
* Regular expression of including patterns
*
*/
protected Pattern includeNameRE;
/**
* Regular expression of excluding patterns
*
*/
protected Pattern excludeNameRE;
/**
*Constructor for the ElementAttributeMatching object
*
* @param includeName Description of Parameter
* @param excludeName Description of Parameter
* @exception PatternSyntaxException Description of Exception
*/
public ElementAttributeMatching(String includeName, String excludeName) throws PatternSyntaxException {
includeNameRE = Pattern.compile(includeName, Pattern.CASE_INSENSITIVE);
excludeNameRE = Pattern.compile(excludeName, Pattern.CASE_INSENSITIVE);
}
/**
* Return true iff element_name attr_name pair is not matched by exclude-name,
* but is matched by include-name
* @param element_name
* @param attr_name
* @param value TODO
*
* @return boolean true iff value of attribute_name should get rewritten, else
* false.
*/
public boolean matchesElementAttribute(String element_name, String attr_name, String value) {
String element_attr_name = canonicalizeElementAttribute(element_name, attr_name, value);
if (excludeNameRE != null && includeNameRE != null) {
return !matchesExcludesElementAttribute(element_attr_name) &&
matchesIncludesElementAttribute(element_attr_name);
} else {
return false;
}
}
/**
* Build from elementname, and attribute name a single string.
* <p>
* String concatenated <code>element name + "/@" + attribute name</code>
* is matched against the include and excluding patterns.
* </p>
* @param element_name Description of Parameter
* @param attr_name Description of Parameter
* @param value The value
*
* @return Description of the Returned Value
*/
private String canonicalizeElementAttribute(String element_name, String attr_name, String value) {
return element_name + "/@" + attr_name + "=" + value;
}
/**
* Return true iff element_name attr_name pair is matched by exclude-name.
*
* @param element_attr_name
* @return boolean true iff exclude-name matches element_name, attr_name, else
* false.
*/
private boolean matchesExcludesElementAttribute(String element_attr_name) {
boolean match = excludeNameRE.matcher(element_attr_name).lookingAt();
return match;
}
/**
* Return true iff element_name attr_name pair is matched by include-name.
*
* @param element_attr_name
* @return boolean true iff include-name matches element_name, attr_name, else
* false.
*/
private boolean matchesIncludesElementAttribute(String element_attr_name) {
boolean match = includeNameRE.matcher(element_attr_name).lookingAt();
return match;
}
}
}
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