helm/uwobo/src/it/unibo/cs/helm/uwobo/Servlet.java

   1 /* Copyright (C) 2001, HELM Team
   2  *
   3  * This file is part of UWOBO, developed at the Computer Science
   4  * Department, University of Bologna, Italy.
   5  *
   6  * UWOBO is free software; you can redistribute it and/or
   7  * modify it under the terms of the GNU General Public License
   8  * as published by the Free Software Foundation; either version 2
   9  * of the License, or (at your option) any later version.
  10  *
  11  * UWOBO is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14  * GNU General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU General Public License
  17  * along with UWOBO; if not, write to the Free Software
  18  * Foundation, Inc., 59 Temple Place - Suite 330, Boston,
  19  * MA  02111-1307, USA.
  20  *
  21  * For details, see the UWOBO World-Wide-Web page,
  22  * http://cs.unibo.it/helm/uwobo
  23  */
  24
  25 package it.unibo.cs.helm.uwobo;
  26
  27 import java.io.*;
  28 import java.util.*;
  29 import javax.servlet.*;
  30 import javax.servlet.http.*;
  31 import javax.xml.transform.*;
  32 import org.xml.sax.*;
  33
  34 // WARNING: next comment is obsolete!!!!!
  35 /*
  36 *
  37 * usage:
  38 *   http://hostname/helm/servlet/uwobo/help
  39 *   http://hostname/helm/servlet/uwobo/add?bind=key,stylesheet[&bind=key,stylesheet]*
  40 *   http://hostname/helm/servlet/uwobo/remove[?keys=key_1,...,key_n]
  41 *   http://hostname/helm/servlet/uwobo/list
  42 *   http://hostname/helm/servlet/uwobo/reload[?keys=key_1,...,key_n]
  43 *   http://hostname/helm/servlet/uwobo/apply?xmluri=xmldata&keys=key_1,...,key_n[&param.name=value]*[&param.key.name=value]*[&prop.name=[value]]*
  44 *
  45 * example:
  46 *   http://aristotele/helm/servlet/uwobo/add?bind=foo1,file:///D:/Archivio/Progetti/helm/resources/xsl/foo1.xsl
  47 *   http://aristotele/helm/servlet/uwobo/add?bind=foo2,file:///D:/Archivio/Progetti/helm/resources/xsl/foo2.xsl
  48 *   http://aristotele/helm/servlet/uwobo/apply?xmluri=file:///D:/Archivio/Progetti/helm/resources/xsl/foo.xml&keys=foo1,foo2
  49 *
  50 * installation notes (Tomcat):
  51 *       replace parser.jar and jaxp.jar from /lib with xerces.jar and add xalan.jar
  52 *
  53 *       add in conf/server.xml
  54 *               <Context path="/helm"
  55 *                       docBase="webapps/helm"
  56 *                       crossContext="false"
  57 *                       debug="0"
  58 *                       reloadable="true" >
  59 *               </Context>
  60 *
  61 *       add in uriworkermap.properties
  62 *               /helm/*=ajp12
  63 *
  64 *
  65 * @author The HELM team
  66 */
  67 public class Servlet extends HttpServlet {
  68
  69    public static final String[] usage = {
  70       "http://<i>hostname</i>/helm/servlet/uwobo/help",
  71       "http://<i>hostname</i>/helm/servlet/uwobo/add?bind=<i>key</i>,<i>stylesheet</i>[&bind=<i>key</i>,<i>stylesheet</i>]*",
  72       "http://<i>hostname</i>/helm/servlet/uwobo/remove[?keys=<i>key_1,...,key_n</i>]",
  73       "http://<i>hostname</i>/helm/servlet/uwobo/list",
  74       "http://<i>hostname</i>/helm/servlet/uwobo/reload[?keys=<i>key_1,...,key_n</i>]",
  75       "http://<i>hostname</i>/helm/servlet/uwobo/apply?xmluri=<i>xmldata</i>&keys=<i>key_1,...,key_n</i>[&param.<i>name</i>=<i>value</i>]*[&param.<i>key</i>.<i>name</i>=<i>value</i>]*[&prop.<i>name</i>=[<i>value</i>]]*"
  76    };
  77    public static final String help;
  78
  79    static {
  80       StringBuffer sb = new StringBuffer();
  81       sb.append("<ul>");
  82       for (int i=0; i<usage.length; i++)
  83          sb.append("<li>").append(usage[i]).append("</li>");
  84       sb.append("</ul>");
  85       help = sb.toString();
  86    }
  87
  88    private Server server;
  89
  90    public void init(ServletConfig config)
  91    throws ServletException
  92    {
  93       super.init(config);
  94
  95       System.out.println("UWOBO init");
  96       server = new Server();
  97    }
  98
  99    private static String[] split(final String s, final String delim)
 100    {
 101       String[] res = {null};
 102       if (s == null) return res;
 103       StringTokenizer st = new StringTokenizer(s, delim);
 104       res = new String[st.countTokens()];
 105       for (int i = 0; i < res.length; i++) res[i] = st.nextToken();
 106       return res;
 107    }
 108
 109    private static String[] split2(final String s, final String delim)
 110    {
 111       String[] res = new String[2];
 112       StringTokenizer st = new StringTokenizer(s);
 113       res[0] = st.nextToken(delim); res[1] = st.nextToken("").substring(1);
 114       return res;
 115    }
 116
 117    private void html_open(HttpServletResponse resp, ServletOutputStream out)
 118    throws IOException
 119    {
 120       resp.setContentType("text/html");
 121       out.println("<html><body bgcolor=\"#ffffff\"><h1>" + server.PACKAGE + " servlet</h1>");
 122    }
 123
 124    private void html_close(ServletOutputStream out)
 125    throws IOException
 126    {
 127       out.println("<p>done</p></body></html>");
 128       out.close();
 129    }
 130
 131    private String msg_out(String message)
 132    {
 133       return message+"<br />";
 134    }
 135
 136    private String exc_out(String message, Exception e)
 137    {
 138       if (message == null)
 139       {
 140          message = e.getClass().getName();
 141          message = message.substring(message.lastIndexOf('.')+1);
 142       }
 143       String local = e.getLocalizedMessage();
 144       local = local.substring(local.lastIndexOf(':')+1);
 145       return "<b style=\"color: red\">"+message+": "+local+"</b><br />";
 146    }
 147
 148    public void doGet(HttpServletRequest request, HttpServletResponse response)
 149    throws ServletException, IOException
 150    {
 151       ServletOutputStream out = response.getOutputStream();
 152       String log = "";
 153
 154       response.setHeader("Cache-Control", "no-cache");
 155       response.setHeader("Pragma", "no-cache");
 156       response.setHeader("Expires", "0");
 157       System.out.println("UWOBO "+request.getPathInfo());
 158
 159       try {
 160          final String cmd = request.getPathInfo();
 161          if (cmd == null) {
 162             sendError(response, out, "unknown command", help); return;
 163          }
 164          if (cmd.equals("/add")) {
 165             final String[] xslkey = request.getParameterValues("bind");
 166             if (xslkey == null) {
 167                sendError(response, out, "bad parameters", usage[1]); return;
 168             }
 169             html_open(response, out);
 170             for (int i = 0; i < xslkey.length; i++) {
 171                final String data[] = split2(xslkey[i], ",");
 172                out.println(msg_out("adding stylesheet "+data[0]+" ("+data[1]+")"));
 173                try {
 174                   log = server.add(data[1], data[0]);
 175                   if(!log.equals(""))
 176                      out.println(msg_out(log));
 177                 } catch (TransformerConfigurationException tce) {
 178                   out.println(exc_out("Stylesheet Error", tce));
 179                } catch (Exception e) {
 180                   out.println(exc_out(null, e));
 181                }
 182             }
 183             html_close(out); return;
 184          }
 185          if (cmd.equals("/apply")) {
 186             final String infile = request.getParameter("xmluri");
 187             final String keys = request.getParameter("keys");
 188
 189             if (infile == null || keys == null) {
 190                sendError(response, out, "bad parameters", usage[6]); return;
 191             }
 192
 193             final String[] keyName = split(keys, ",");
 194             final Key[] keySeq = new Key[keyName.length];
 195             for (int i = 0; i < keySeq.length; i++) {
 196                keySeq[i] = new Key();
 197                keySeq[i].name = keyName[i];
 198                keySeq[i].params = new HashMap();
 199             }
 200
 201             final Properties props = new Properties();
 202             final Enumeration e = request.getParameterNames();
 203             while (e.hasMoreElements()) {
 204                String param = (String) e.nextElement();
 205                if (param.startsWith("param.")) {
 206                   final String name = param.substring(6);
 207                   final String value = request.getParameter(param);
 208                   final String[] keyParam = split(name, ".");
 209                   if (keyParam.length == 1) {
 210                      // this is a global parameter
 211                      Server.log("global parameter: " + keyParam[0] + " = " + value);
 212                      for (int i = 0; i < keySeq.length; i++)
 213                         // we add the global parameter only if there is no
 214                         // local parameter with the same name
 215                         if (!keySeq[i].params.containsKey(keyParam[0]))
 216                            keySeq[i].params.put(keyParam[0], value);
 217                   } else
 218                   if (keyParam.length == 2) {
 219                      // this is a local parameter
 220                      Server.log("local parameter: " + keyParam[0] + "." + keyParam[1] + " = " + value);
 221                      for (int i = 0; i < keySeq.length; i++) {
 222                         if (keySeq[i].name.equals(keyParam[0]))
 223                            keySeq[i].params.put(keyParam[1], value);
 224                      }
 225                   } else {
 226                      sendError(response, out, "bad parameters", usage[6]); return;
 227                   }
 228                } else
 229                if (param.startsWith("prop.")) {
 230                   final String name = param.substring(5);
 231                   final String value = request.getParameter(param);
 232                   Server.log("property: " + name + " = " + value);
 233                   props.setProperty(name, value);
 234                }
 235             }
 236
 237             String contentType = props.getProperty(OutputKeys.MEDIA_TYPE);
 238             if (contentType == null && keySeq.length > 0)
 239                contentType = server.getContentType(keySeq[keySeq.length - 1].name);
 240             else if (contentType == null)
 241                contentType = "text/xml";
 242             response.setContentType(contentType);
 243             Server.log("content type: " + contentType);
 244
 245             try {
 246                out = response.getOutputStream();
 247                server.apply(infile, out, keySeq, props);
 248                out.close();
 249             } catch (TransformerConfigurationException tce) {
 250                sendError(response, out, exc_out("stylesheet error", tce), "");
 251             } catch (Exception ee) {
 252                sendError(response, out, exc_out(null, ee), "");
 253             }
 254             return;
 255          }
 256          if (cmd.equals("/remove")) {
 257             final String key = request.getParameter("keys");
 258             final String [] data = split(key, ",");
 259             html_open(response, out);
 260             for (int i = 0; i < data.length; i++) {
 261                if (data[i] == null) {
 262                   out.println(msg_out("removing all keys"));
 263                   ArrayList res;
 264                   res = server.removeAll();
 265                   Iterator j = res.iterator();
 266                   while (j.hasNext())
 267                      out.println(msg_out((String)j.next()));
 268                } else {
 269                   out.println(msg_out("removing key "+data[i]));
 270                   out.println(msg_out(server.remove(data[i])));
 271                }
 272             }
 273             html_close(out); return;
 274          }
 275          if (cmd.equals("/list")) {
 276             html_open(response, out);
 277             out.println("<p>stylesheet list:</p><ul>");
 278
 279             Iterator i = server.list().iterator();
 280             while (i.hasNext())
 281                out.println("<li>"+i.next()+"</li>");
 282             out.println("</ul>"); html_close(out); return;
 283          }
 284          if (cmd.equals("/reload")) {
 285             final String key = request.getParameter("keys");
 286             final String [] data = split(key, ",");
 287             html_open(response, out);
 288             for (int i = 0; i < data.length; i++) {
 289                try {
 290                   if (data[i] == null) {
 291                      out.println(msg_out("reloading all keys"));
 292                      ArrayList res;
 293                      res = server.reloadAll();
 294                      Iterator j = res.iterator();
 295                      while(j.hasNext())
 296                         out.println(msg_out((String)j.next()));
 297                   } else {
 298                      out.println(msg_out("reloading key "+data[i]));
 299                      out.println(msg_out(server.reload(data[i])));
 300                   }
 301                } catch (TransformerConfigurationException tce) {
 302                   out.println(exc_out("Stylesheet Error", tce));
 303                } catch (Exception e) {
 304                   out.println(exc_out(null, e));
 305                }
 306             }
 307             html_close(out); return;
 308          }
 309          if (cmd.equals("/help")) {
 310             html_open(response, out);
 311             out.println("<h2>Version "+server.VERSION+"</h1>");
 312             out.println("<b>compiled "+server.DATE+" at "+server.TIME.substring(0,2)+":"+server.TIME.substring(2)+"</b>");
 313             if(Server.SERIALIZATION_DIR.equals("")) {
 314                out.println("<p><b>Stylesheet serialization is off.</b>");
 315                out.println("(To turn it on, choose a non-empty value for the " +
 316                   "SERIALIZATION_DIR property.)</p>");
 317             } else
 318                out.println("<p><b>Serialized stylesheed are stored in &quot;" +
 319                   Server.SERIALIZATION_DIR + "&quot;.</b></p>");
 320             out.println("<p>usage:</p>"+help+"</body></html>");
 321             html_close(out); return;
 322          }
 323          sendError(response, out, "unknown command", help); return;
 324       } catch (Exception e) {
 325          sendError(response, out, exc_out(null, e),"");
 326          return;
 327       }
 328    }
 329
 330    private void sendError(HttpServletResponse resp, ServletOutputStream out,
 331                           String msg, String usage)
 332    throws IOException
 333    {
 334       html_open(resp, out);
 335       out.println("<p>"+msg+"</p>usage: "+usage);
 336       html_close(out);
 337    }
 338
 339    public String getServletInfo()
 340    {
 341       return "The UWOBO servlet";
 342    }
 343 }