/*
* Copyright (c) 2009, 2010, 2011, 2012, 2013, 2014, B3log Team
*
* Licensed 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.b3log.solo.processor;
import java.io.BufferedInputStream;
import java.io.File;
import java.io.FileOutputStream;
import java.io.InputStream;
import java.io.OutputStream;
import java.net.URL;
import java.util.Enumeration;
import java.util.Random;
import java.util.zip.ZipEntry;
import java.util.zip.ZipFile;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;
import org.apache.commons.io.IOUtils;
import org.b3log.latke.Latkes;
import org.b3log.latke.RuntimeEnv;
import org.b3log.latke.image.Image;
import org.b3log.latke.image.ImageService;
import org.b3log.latke.image.ImageServiceFactory;
import org.b3log.latke.logging.Level;
import org.b3log.latke.logging.Logger;
import org.b3log.latke.servlet.HTTPRequestContext;
import org.b3log.latke.servlet.HTTPRequestMethod;
import org.b3log.latke.servlet.annotation.RequestProcessing;
import org.b3log.latke.servlet.annotation.RequestProcessor;
import org.b3log.latke.servlet.renderer.PNGRenderer;
import org.b3log.solo.SoloServletListener;
/**
* Captcha processor.
*
* <p>
* Checkout <a href="http://toy-code.googlecode.com/svn/trunk/CaptchaGenerator">
* the sample captcha generator</a> for more details.
* </p>
*
* @author <a href="http://88250.b3log.org">Liang Ding</a>
* @version 1.1.0.3, Jan 4, 2013
* @since 0.3.1
*/
@RequestProcessor
public class CaptchaProcessor {
/**
* Logger.
*/
private static final Logger LOGGER = Logger.getLogger(CaptchaProcessor.class.getName());
/**
* Images service.
*/
private static final ImageService IMAGE_SERVICE = ImageServiceFactory.getImageService();
/**
* Key of captcha.
*/
public static final String CAPTCHA = "captcha";
/**
* Captchas.
*/
private Image[] captchas;
/**
* Count of static captchas.
*/
private static final int CAPTCHA_COUNT = 100;
/**
* Gets captcha.
*
* @param context the specified context
*/
@RequestProcessing(value = "/captcha.do", method = HTTPRequestMethod.GET)
public void get(final HTTPRequestContext context) {
final PNGRenderer renderer = new PNGRenderer();
context.setRenderer(renderer);
if (null == captchas) {
loadCaptchas();
}
try {
final HttpServletRequest request = context.getRequest();
final HttpServletResponse response = context.getResponse();
final Random random = new Random();
final int index = random.nextInt(CAPTCHA_COUNT);
final Image captchaImg = captchas[index];
final String captcha = captchaImg.getName();
final HttpSession httpSession = request.getSession(false);
if (null != httpSession) {
LOGGER.log(Level.DEBUG, "Captcha[{0}] for session[id={1}]", new Object[] {captcha, httpSession.getId()});
httpSession.setAttribute(CAPTCHA, captcha);
}
response.setHeader("Pragma", "no-cache");
response.setHeader("Cache-Control", "no-cache");
response.setDateHeader("Expires", 0);
renderer.setImage(captchaImg);
} catch (final Exception e) {
LOGGER.log(Level.ERROR, e.getMessage(), e);
}
}
/**
* Loads captcha.
*/
private synchronized void loadCaptchas() {
LOGGER.info("Loading captchas....");
try {
captchas = new Image[CAPTCHA_COUNT];
ZipFile zipFile;
if (RuntimeEnv.LOCAL == Latkes.getRuntimeEnv()) {
final InputStream inputStream = SoloServletListener.class.getClassLoader().getResourceAsStream("captcha_static.zip");
final File file = File.createTempFile("b3log_captcha_static", null);
final OutputStream outputStream = new FileOutputStream(file);
IOUtils.copy(inputStream, outputStream);
zipFile = new ZipFile(file);
IOUtils.closeQuietly(inputStream);
IOUtils.closeQuietly(outputStream);
} else {
final URL captchaURL = SoloServletListener.class.getClassLoader().getResource("captcha_static.zip");
zipFile = new ZipFile(captchaURL.getFile());
}
final Enumeration<? extends ZipEntry> entries = zipFile.entries();
int i = 0;
while (entries.hasMoreElements()) {
final ZipEntry entry = entries.nextElement();
final BufferedInputStream bufferedInputStream = new BufferedInputStream(zipFile.getInputStream(entry));
final byte[] captchaCharData = new byte[bufferedInputStream.available()];
bufferedInputStream.read(captchaCharData);
bufferedInputStream.close();
final Image image = IMAGE_SERVICE.makeImage(captchaCharData);
image.setName(entry.getName().substring(0, entry.getName().lastIndexOf('.')));
captchas[i] = image;
i++;
}
zipFile.close();
} catch (final Exception e) {
LOGGER.error("Can not load captchs!");
throw new IllegalStateException(e);
}
LOGGER.info("Loaded captch images");
}
}