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
  77   static {
  78     HINTS = new Hashtable<DecodeHintType, Object>(3);
  79     HINTS.put(DecodeHintType.TRY_HARDER, Boolean.TRUE);
  80   }
  81
  82   private HttpClient client;
  83   private DiskFileItemFactory diskFileItemFactory;
  84   private Timer emailTimer;
  85
  86   @Override
  87   public void init(ServletConfig servletConfig) throws ServletException {
  88
  89     Logger logger = Logger.getLogger("com.google.zxing");
  90     logger.addHandler(new ServletContextLogHandler(servletConfig.getServletContext()));
  91
  92     String emailAddress = servletConfig.getInitParameter("emailAddress");
  93     String emailPassword = servletConfig.getInitParameter("emailPassword");
  94     if (emailAddress == null || emailPassword == null) {
  95       throw new ServletException("emailAddress or emailPassword not specified");
  96     }
  97
  98     HttpParams params = new BasicHttpParams();
  99     HttpProtocolParams.setVersion(params, HttpVersion.HTTP_1_1);
 100
 101     SchemeRegistry registry = new SchemeRegistry();
 102     registry.register(new Scheme("http", PlainSocketFactory.getSocketFactory(), 80));
 103     registry.register(new Scheme("https", SSLSocketFactory.getSocketFactory(), 443));
 104
 105     client = new DefaultHttpClient(new ThreadSafeClientConnManager(params, registry), params);
 106
 107     diskFileItemFactory = new DiskFileItemFactory();
 108
 109     Authenticator emailAuthenticator = new EmailAuthenticator(emailAddress, emailPassword);
 110     emailTimer = new Timer("Email decoder timer", true);
 111     emailTimer.schedule(new DecodeEmailTask(emailAddress, emailAuthenticator), 0L, EMAIL_CHECK_INTERVAL);
 112
 113     log.info("DecodeServlet configured");
 114   }
 115
 116   @Override
 117   protected void doGet(HttpServletRequest request, HttpServletResponse response) throws IOException {
 118
 119     String imageURIString = request.getParameter("u");
 120     if (imageURIString == null || imageURIString.length() == 0) {
 121       response.sendRedirect("badurl.jspx");
 122       return;
 123     }
 124
 125     if (!(imageURIString.startsWith("http://") || imageURIString.startsWith("https://"))) {
 126       imageURIString = "http://" + imageURIString;
 127     }
 128
 129     URI imageURI;
 130     try {
 131       imageURI = new URI(imageURIString);
 132     } catch (URISyntaxException urise) {
 133       response.sendRedirect("badurl.jspx");
 134       return;
 135     }
 136
 137     HttpGet getRequest = new HttpGet(imageURI);
 138
 139     try {
 140       HttpResponse getResponse = client.execute(getRequest);
 141       if (getResponse.getStatusLine().getStatusCode() != HttpServletResponse.SC_OK) {
 142         response.sendRedirect("badurl.jspx");
 143         return;
 144       }
 145       if (!isSizeOK(getResponse)) {
 146         response.sendRedirect("badimage.jspx");
 147         return;
 148       }
 149       log.info("Decoding " + imageURI);
 150       InputStream is = getResponse.getEntity().getContent();
 151       try {
 152         processStream(is, response);
 153       } finally {
 154         is.close();
 155       }
 156     } catch (InterruptedException ie) {
 157       getRequest.abort();
 158       response.sendRedirect("badurl.jspx");
 159     } catch (HttpException he) {
 160       getRequest.abort();
 161       response.sendRedirect("badurl.jspx");
 162     }
 163
 164   }
 165
 166   @Override
 167   protected void doPost(HttpServletRequest request, HttpServletResponse response)
 168           throws ServletException, IOException {
 169
 170     if (!ServletFileUpload.isMultipartContent(request)) {
 171       response.sendRedirect("badimage.jspx");
 172       return;
 173     }
 174
 175     ServletFileUpload upload = new ServletFileUpload(diskFileItemFactory);
 176     upload.setFileSizeMax(MAX_IMAGE_SIZE);
 177
 178     // Parse the request
 179     try {
 180       for (FileItem item : (List<FileItem>) upload.parseRequest(request)) {
 181         if (!item.isFormField()) {
 182           if (item.getSize() <= MAX_IMAGE_SIZE) {
 183             log.info("Decoding uploaded file");
 184             InputStream is = item.getInputStream();
 185             try {
 186               processStream(is, response);
 187             } finally {
 188               is.close();
 189             }
 190           } else {
 191             throw new ServletException("File is too large: " + item.getSize());
 192           }
 193           break;
 194         }
 195       }
 196     } catch (FileUploadException fue) {
 197       response.sendRedirect("badimage.jspx");
 198     }
 199
 200   }
 201
 202   private static void processStream(InputStream is, HttpServletResponse response) throws IOException {
 203     BufferedImage image = ImageIO.read(is);
 204     if (image == null) {
 205       response.sendRedirect("badimage.jspx");
 206       return;
 207     }
 208
 209     Reader reader = new MultiFormatReader();
 210     Result result;
 211     try {
 212       result = reader.decode(new BufferedImageMonochromeBitmapSource(image), HINTS);
 213     } catch (ReaderException re) {
 214       log.info("DECODE FAILED: " + re.toString());
 215       response.sendRedirect("notfound.jspx");
 216       return;
 217     }
 218
 219     response.setContentType("text/plain");
 220     response.setCharacterEncoding("UTF-8");
 221     Writer out = new OutputStreamWriter(response.getOutputStream(), "UTF-8");
 222     try {
 223       out.write(result.getText());
 224     } finally {
 225       out.close();
 226     }
 227   }
 228
 229   private static boolean isSizeOK(HttpMessage getResponse) {
 230     Header lengthHeader = getResponse.getLastHeader("Content-Length");
 231     if (lengthHeader != null) {
 232       long length = Long.parseLong(lengthHeader.getValue());
 233       if (length > MAX_IMAGE_SIZE) {
 234         return false;
 235       }
 236     }
 237     return true;
 238   }
 239
 240   @Override
 241   public void destroy() {
 242     log.config("DecodeServlet shutting down...");
 243     emailTimer.cancel();
 244   }
 245
 246 }