zxingorg/src/com/google/zxing/web/DecodeServlet.java

   1 /*
   2  * Copyright 2008 Google Inc.
   3  *
   4  * Licensed under the Apache License, Version 2.0 (the "License");
   5  * you may not use this file except in compliance with the License.
   6  * You may obtain a copy of the License at
   7  *
   8  *      http://www.apache.org/licenses/LICENSE-2.0
   9  *
  10  * Unless required by applicable law or agreed to in writing, software
  11  * distributed under the License is distributed on an "AS IS" BASIS,
  12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  13  * See the License for the specific language governing permissions and
  14  * limitations under the License.
  15  */
  16
  17 package com.google.zxing.web;
  18
  19 import com.google.zxing.DecodeHintType;
  20 import com.google.zxing.MultiFormatReader;
  21 import com.google.zxing.Reader;
  22 import com.google.zxing.ReaderException;
  23 import com.google.zxing.Result;
  24 import com.google.zxing.client.j2se.BufferedImageMonochromeBitmapSource;
  25 import org.apache.commons.fileupload.FileItem;
  26 import org.apache.commons.fileupload.FileUploadException;
  27 import org.apache.commons.fileupload.disk.DiskFileItemFactory;
  28 import org.apache.commons.fileupload.servlet.ServletFileUpload;
  29 import org.apache.http.Header;
  30 import org.apache.http.HttpException;
  31 import org.apache.http.HttpMessage;
  32 import org.apache.http.HttpResponse;
  33 import org.apache.http.HttpVersion;
  34 import org.apache.http.client.HttpClient;
  35 import org.apache.http.client.methods.HttpGet;
  36 import org.apache.http.conn.PlainSocketFactory;
  37 import org.apache.http.conn.Scheme;
  38 import org.apache.http.conn.SchemeRegistry;
  39 import org.apache.http.conn.ssl.SSLSocketFactory;
  40 import org.apache.http.impl.client.DefaultHttpClient;
  41 import org.apache.http.impl.conn.tsccm.ThreadSafeClientConnManager;
  42 import org.apache.http.params.BasicHttpParams;
  43 import org.apache.http.params.HttpParams;
  44 import org.apache.http.params.HttpProtocolParams;
  45
  46 import javax.imageio.ImageIO;
  47 import javax.mail.Authenticator;
  48 import javax.servlet.ServletConfig;
  49 import javax.servlet.ServletException;
  50 import javax.servlet.http.HttpServlet;
  51 import javax.servlet.http.HttpServletRequest;
  52 import javax.servlet.http.HttpServletResponse;
  53 import java.awt.image.BufferedImage;
  54 import java.io.IOException;
  55 import java.io.InputStream;
  56 import java.io.OutputStreamWriter;
  57 import java.io.Writer;
  58 import java.net.URI;
  59 import java.net.URISyntaxException;
  60 import java.util.Hashtable;
  61 import java.util.List;
  62 import java.util.Timer;
  63 import java.util.logging.Logger;
  64
  65 /**
  66  * @author Sean Owen
  67  */
  68 public final class DecodeServlet extends HttpServlet {
  69
  70         private static final long MAX_IMAGE_SIZE = 500000L;
  71   private static final long EMAIL_CHECK_INTERVAL = 60000L;
  72
  73   private static final Logger log = Logger.getLogger(DecodeServlet.class.getName());
  74
  75   static final Hashtable<DecodeHintType, Object> HINTS;
  76   static {
  77     HINTS = new Hashtable<DecodeHintType, Object>(3);
  78     HINTS.put(DecodeHintType.TRY_HARDER, Boolean.TRUE);
  79   }
  80
  81   private HttpClient client;
  82         private DiskFileItemFactory diskFileItemFactory;
  83   private Timer emailTimer;
  84
  85   @Override
  86         public void init(ServletConfig servletConfig) throws ServletException {
  87
  88     Logger logger = Logger.getLogger("com.google.zxing");
  89     logger.addHandler(new ServletContextLogHandler(servletConfig.getServletContext()));
  90
  91     String emailAddress = servletConfig.getInitParameter("emailAddress");
  92     String emailPassword = servletConfig.getInitParameter("emailPassword");
  93     if (emailAddress == null || emailPassword == null) {
  94       throw new ServletException("emailAddress or emailPassword not specified");
  95     }
  96
  97     HttpParams params = new BasicHttpParams();
  98     HttpProtocolParams.setVersion(params, HttpVersion.HTTP_1_1);
  99
 100     SchemeRegistry registry = new SchemeRegistry();
 101     registry.register(new Scheme("http", PlainSocketFactory.getSocketFactory(), 80));
 102     registry.register(new Scheme("https", SSLSocketFactory.getSocketFactory(), 443));
 103
 104     client = new DefaultHttpClient(new ThreadSafeClientConnManager(params, registry), params);
 105
 106     diskFileItemFactory = new DiskFileItemFactory();
 107
 108     Authenticator emailAuthenticator = new EmailAuthenticator(emailAddress, emailPassword);
 109     emailTimer = new Timer("Email decoder timer", true);
 110     emailTimer.schedule(new DecodeEmailTask(emailAuthenticator), 0L, EMAIL_CHECK_INTERVAL);
 111
 112     log.info("DecodeServlet configured");
 113   }
 114
 115         @Override
 116         protected void doGet(HttpServletRequest request, HttpServletResponse response) throws IOException {
 117
 118                 String imageURIString = request.getParameter("u");
 119                 if (imageURIString == null || imageURIString.length() == 0) {
 120                         response.sendRedirect("badurl.jspx");
 121                         return;
 122                 }
 123
 124                 if (!(imageURIString.startsWith("http://") || imageURIString.startsWith("https://"))) {
 125                         imageURIString = "http://" + imageURIString;
 126                 }
 127
 128                 URI imageURI;
 129                 try {
 130                         imageURI = new URI(imageURIString);
 131                 } catch (URISyntaxException urise) {
 132                         response.sendRedirect("badurl.jspx");
 133                         return;
 134                 }
 135
 136     HttpGet getRequest = new HttpGet(imageURI);
 137
 138                 try {
 139       HttpResponse getResponse = client.execute(getRequest);
 140       if (getResponse.getStatusLine().getStatusCode() != HttpServletResponse.SC_OK) {
 141                                 response.sendRedirect("badurl.jspx");
 142                                 return;
 143                         }
 144                         if (!isSizeOK(getResponse)) {
 145                                 response.sendRedirect("badimage.jspx");
 146                                 return;
 147                         }
 148       log.info("Decoding " + imageURI);
 149       InputStream is = getResponse.getEntity().getContent();
 150                         try {
 151                                 processStream(is, response);
 152                         } finally {
 153                                 is.close();
 154                         }
 155     } catch (InterruptedException ie) {
 156       getRequest.abort();
 157       response.sendRedirect("badurl.jspx");
 158     } catch (HttpException he) {
 159       getRequest.abort();
 160       response.sendRedirect("badurl.jspx");
 161                 }
 162
 163         }
 164
 165         @Override
 166         protected void doPost(HttpServletRequest request, HttpServletResponse response)
 167                 throws ServletException, IOException {
 168
 169                 if (!ServletFileUpload.isMultipartContent(request)) {
 170                         response.sendRedirect("badimage.jspx");
 171                         return;
 172                 }
 173
 174                 ServletFileUpload upload = new ServletFileUpload(diskFileItemFactory);
 175                 upload.setFileSizeMax(MAX_IMAGE_SIZE);
 176
 177                 // Parse the request
 178                 try {
 179                         for (FileItem item : (List<FileItem>) upload.parseRequest(request)) {
 180                                 if (!item.isFormField()) {
 181                                         if (item.getSize() <= MAX_IMAGE_SIZE) {
 182             log.info("Decoding uploaded file");
 183                                                 InputStream is = item.getInputStream();
 184                                                 try {
 185                                                         processStream(is, response);
 186                                                 } finally {
 187                                                         is.close();
 188                                                 }
 189                                         } else {
 190                                                 throw new ServletException("File is too large: " + item.getSize());
 191                                         }
 192                                         break;
 193                                 }
 194                         }
 195                 } catch (FileUploadException fue) {
 196                         response.sendRedirect("badimage.jspx");
 197                 }
 198
 199         }
 200
 201         private static void processStream(InputStream is, HttpServletResponse response) throws IOException {
 202                 BufferedImage image = ImageIO.read(is);
 203                 if (image == null) {
 204                         response.sendRedirect("badimage.jspx");
 205                         return;
 206                 }
 207
 208                 Reader reader = new MultiFormatReader();
 209                 Result result;
 210                 try {
 211                         result = reader.decode(new BufferedImageMonochromeBitmapSource(image), HINTS);
 212                 } catch (ReaderException re) {
 213                         log.info("DECODE FAILED: " + re.toString());
 214                         response.sendRedirect("notfound.jspx");
 215                         return;
 216                 }
 217
 218                 response.setContentType("text/plain");
 219                 response.setCharacterEncoding("UTF-8");
 220                 Writer out = new OutputStreamWriter(response.getOutputStream(), "UTF-8");
 221                 try {
 222                         out.write(result.getText());
 223                 } finally {
 224                         out.close();
 225                 }
 226         }
 227
 228         private static boolean isSizeOK(HttpMessage getResponse) {
 229     Header lengthHeader = getResponse.getLastHeader("Content-Length");
 230                 if (lengthHeader != null) {
 231                         long length = Long.parseLong(lengthHeader.getValue());
 232                         if (length > MAX_IMAGE_SIZE) {
 233                                 return false;
 234                         }
 235                 }
 236                 return true;
 237         }
 238
 239         @Override
 240         public void destroy() {
 241     log.config("DecodeServlet shutting down...");
 242     emailTimer.cancel();
 243   }
 244
 245 }