/*
* 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.myfaces.custom.captcha;
import java.awt.Color;
import java.io.IOException;
import java.util.Map;
import javax.faces.FacesException;
import javax.faces.FactoryFinder;
import javax.faces.component.UIComponent;
import javax.faces.context.FacesContext;
import javax.faces.context.FacesContextFactory;
import javax.faces.context.ResponseStream;
import javax.faces.context.ResponseWriter;
import javax.faces.lifecycle.Lifecycle;
import javax.faces.lifecycle.LifecycleFactory;
import javax.faces.render.Renderer;
import javax.servlet.ServletContext;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import org.apache.myfaces.component.html.util.HtmlComponentUtils;
import org.apache.myfaces.component.html.util.ParameterResourceHandler;
import org.apache.myfaces.custom.captcha.util.CAPTCHAConstants;
import org.apache.myfaces.custom.captcha.util.CAPTCHAImageGenerator;
import org.apache.myfaces.custom.captcha.util.CAPTCHAResponseStream;
import org.apache.myfaces.custom.captcha.util.CAPTCHATextGenerator;
import org.apache.myfaces.custom.captcha.util.ColorGenerator;
import org.apache.myfaces.renderkit.html.util.AddResource;
import org.apache.myfaces.renderkit.html.util.AddResourceFactory;
import org.apache.myfaces.renderkit.html.util.ResourceLoader;
import org.apache.myfaces.shared_tomahawk.renderkit.html.HTML;
import org.apache.myfaces.tomahawk.config.TomahawkConfig;
/**
*
* @JSFRenderer
* renderKitId = "HTML_BASIC"
* family = "org.apache.myfaces.CAPTCHA"
* type = "org.apache.myfaces.CAPTCHA"
* @since 1.1.7
* @author Hazem Saleh
*
*/
public class CAPTCHARenderer extends Renderer implements ResourceLoader
{
public void encodeBegin(FacesContext context, UIComponent component)
throws IOException
{
CAPTCHAComponent captchaComponent = (CAPTCHAComponent) component;
generateImageTag(context, captchaComponent);
}
public void encodeEnd(FacesContext context, UIComponent component)
throws IOException
{
super.encodeEnd(context, component);
}
/*
* This helper method is used for generating the img tag that will
* use the (AddResource) to generate the url of the generated image.
*/
private void generateImageTag(FacesContext context,
CAPTCHAComponent component) throws IOException
{
AddResource addResource;
ResponseWriter writer = context.getResponseWriter();
Map params = HtmlComponentUtils.getParameterMap(component);
String url;
String captchaSessionKeyName = component.getCaptchaSessionKeyName();
String width = component.getImageWidth();
String height = component.getImageHeight();
// determine width and height of the generated image.
if (width == null)
{
width = CAPTCHAConstants.DEFAULT_CAPTCHA_WIDTH + "";
}
if (height == null)
{
height = CAPTCHAConstants.DEFAULT_CAPTCHA_HEIGHT + "";
}
writer.startElement(HTML.IMG_ELEM, component);
// constructing the parameter map to be passed to the (AddResource).
if (captchaSessionKeyName != null)
{
params.put(CAPTCHAComponent.ATTRIBUTE_CAPTCHA_SESSION_KEY_NAME,
captchaSessionKeyName);
}
// write the url to trigger the (AddResource).
addResource = AddResourceFactory.getInstance(context);
url = context.getExternalContext().encodeResourceURL(
addResource.getResourceUri(context,
new ParameterResourceHandler(this.getClass(), params)));
// adding dummy parameter to prevent caching.
writer.writeAttribute(HTML.SRC_ATTR, url + "&dummyParameter="
+ System.currentTimeMillis(), null);
// write rest of attributes.
writer.writeAttribute(HTML.WIDTH_ATTR, width, null);
writer.writeAttribute(HTML.HEIGHT_ATTR, height, null);
writer.endElement(HTML.IMG_ELEM);
}
/*
* This method is implemented to be called from the (AddResource).
* It wraps the CAPTCHA image generation.
*/
public void serveResource(ServletContext servletContext,
HttpServletRequest request, HttpServletResponse response,
String resourceUri) throws IOException
{
// get the FacesContext from the ServletContext.
FacesContextFactory facesContextFactory = (FacesContextFactory) FactoryFinder
.getFactory(FactoryFinder.FACES_CONTEXT_FACTORY);
LifecycleFactory lifecycleFactory = (LifecycleFactory) FactoryFinder
.getFactory(FactoryFinder.LIFECYCLE_FACTORY);
Lifecycle lifecycle = lifecycleFactory.getLifecycle(HtmlComponentUtils
.getLifecycleId(servletContext));
FacesContext facesContext = facesContextFactory.getFacesContext(
servletContext, request, response, lifecycle);
facesContext.setResponseStream(new CAPTCHAResponseStream(response
.getOutputStream()));
// render the CAPTCHA.
try
{
try
{
renderCAPTCHA(facesContext);
}
catch (IOException e)
{
throw new FacesException("Could not render the CAPTCHA : "
+ e.getMessage(), e);
}
facesContext.getResponseStream().close();
}
finally
{
facesContext.release();
}
}
/*
* This method is used for rendering the CAPTCHA component.
*/
protected void renderCAPTCHA(FacesContext facesContext) throws IOException
{
// getting CAPTCHA attributes.
HttpServletResponse response = (HttpServletResponse) facesContext
.getExternalContext().getResponse();
ResponseStream out = facesContext.getResponseStream();
Map requestMap = facesContext.getExternalContext()
.getRequestParameterMap();
String captchaSessionKeyName = requestMap.get(
CAPTCHAComponent.ATTRIBUTE_CAPTCHA_SESSION_KEY_NAME).toString();
// construct the CAPTCHA image generator object.
CAPTCHAImageGenerator captchaImageGenerator = new CAPTCHAImageGenerator();
try
{
String captchaText;
Color endingColor = ColorGenerator.generateRandomColor(null);
Color startingColor = ColorGenerator
.generateRandomColor(endingColor);
// Generate random CAPTCHA text.
captchaText = CAPTCHATextGenerator.generateRandomText();
TomahawkConfig config = TomahawkConfig.getCurrentInstance(facesContext);
// Set the generated text in the user session.
facesContext.getExternalContext().getSessionMap().put(
config.isPrefixCaptchaSessionKey() ?
AbstractCAPTCHAComponent.ATTRIBUTE_CAPTCHA_SESSION_KEY_NAME+
"_"+captchaSessionKeyName : captchaSessionKeyName, captchaText);
// Generate the image, the BG color is randomized from starting to ending colors.
captchaImageGenerator.generateImage(response, captchaText,
startingColor, endingColor);
}
finally
{
out.close();
facesContext.responseComplete();
}
}
}