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

   1 package it.unibo.cs.helm.uwobo;
   2
   3 import java.io.*;
   4 import java.util.*;
   5 import javax.servlet.*;
   6 import javax.servlet.http.*;
   7 import javax.xml.transform.*;
   8 import org.xml.sax.*;
   9
  10 /*
  11 *
  12 * usage:
  13 *   http://aristotele/helm/servlet/uwobo/help
  14 *   http://aristotele/helm/servlet/uwobo/add?xsluri=&key=
  15 *   http://aristotele/helm/servlet/uwobo/remove[?key=]
  16 *   http://aristotele/helm/servlet/uwobo/list
  17 *   http://aristotele/helm/servlet/uwobo/reload[?key=]
  18 *   http://aristotele/helm/servlet/uwobo/update[?key=]
  19 *   http://aristotele/helm/servlet/uwobo/apply?xmluri=&keys=[&param.=]*
  20 *
  21 * example:
  22 *   http://aristotele/helm/servlet/uwobo/add?xsluri=file:///D:/Archivio/Progetti/helm/resources/xsl/foo1.xsl&key=foo1
  23 *   http://aristotele/helm/servlet/uwobo/add?xsluri=file:///D:/Archivio/Progetti/helm/resources/xsl/foo2.xsl&key=foo2
  24 *   http://aristotele/helm/servlet/uwobo/apply?xmluri=file:///D:/Archivio/Progetti/helm/resources/xsl/foo.xml&key=foo1&key=foo2
  25 *
  26 * installation notes (Tomcat):
  27 *       replace parser.jar and jaxp.jar from /lib with xerces.jar
  28 *
  29 *       add in conf/server.xml
  30 *               <Context path="/helm"
  31 *                       docBase="webapps/helm"
  32 *                       crossContext="false"
  33 *                       debug="0"
  34 *                       reloadable="true" >
  35 *               </Context>
  36 *
  37 *       add in uriworkermap.properties
  38 *               /helm/*=ajp12
  39 *
  40 * bugs:
  41 *       directory base stylesheet inclusi
  42 *
  43 * @author The HELM team
  44 */
  45 public class Servlet extends HttpServlet {
  46
  47    public static final String[] usage = {
  48       "http://<i>hostname</i>/helm/servlet/uwobo/help",
  49       "http://<i>hostname</i>/helm/servlet/uwobo/add?key=<i>key</i>,<i>stylesheet</i>[&key=<i>key</i>,<i>stylesheet</i>]*",
  50       "http://<i>hostname</i>/helm/servlet/uwobo/remove[?keys=<i>key_1,...,key_n</i>]",
  51       "http://<i>hostname</i>/helm/servlet/uwobo/list",
  52       "http://<i>hostname</i>/helm/servlet/uwobo/reload[?keys=<i>key_1,...,key_n</i>]",
  53       "http://<i>hostname</i>/helm/servlet/uwobo/update[?keys=<i>key_1,...,key_n</i>]",
  54       "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>]]*"
  55    };
  56    public static final String help;
  57
  58    static {
  59       StringBuffer sb = new StringBuffer();
  60       sb.append("<ul>");
  61       for (int i=0; i<usage.length; i++)
  62          sb.append("<li>").append(usage[i]).append("</li>");
  63       sb.append("</ul>");
  64       help = sb.toString();
  65    }
  66
  67    private Server server;
  68
  69    public void init(ServletConfig config)
  70    throws ServletException
  71    {
  72       super.init(config);
  73
  74       System.out.println("UWOBO init");
  75       server = new Server();
  76    }
  77
  78    private static String[] split(final String s, final String delim)
  79    {
  80       String[] res = {null};
  81       if (s == null) return res;
  82       StringTokenizer st = new StringTokenizer(s, delim);
  83       res = new String[st.countTokens()];
  84       for (int i = 0; i < res.length; i++) res[i] = st.nextToken();
  85       return res;
  86    }
  87
  88    private static String[] split2(final String s, final String delim)
  89    {
  90       String[] res = new String[2];
  91       StringTokenizer st = new StringTokenizer(s);
  92       res[0] = st.nextToken(delim); res[1] = st.nextToken("").substring(1);
  93       return res;
  94    }
  95
  96    private void html_open(HttpServletResponse resp, ServletOutputStream out)
  97    throws IOException
  98    {
  99       resp.setContentType("text/html");
 100       out.println("<html><body bgcolor=\"#ffffff\"><h1>Uwobo servlet</h1>");
 101    }
 102
 103    private void html_close(ServletOutputStream out)
 104    throws IOException
 105    {
 106       out.println("<p>done</p></body></html>");
 107       out.close();
 108    }
 109
 110    private String msg_out(String message)
 111    {
 112       return message+"<br>";
 113    }
 114
 115    private String exc_out(String message, Exception e)
 116    {
 117       if (message == null)
 118       {
 119          message = e.getClass().getName();
 120          message = message.substring(message.lastIndexOf('.')+1);
 121       }
 122       String local = e.getLocalizedMessage();
 123       local = local.substring(local.lastIndexOf(':')+1);
 124       return "<b>"+message+": "+local+"</b><br>";
 125    }
 126
 127    public void doGet(HttpServletRequest request, HttpServletResponse response)
 128    throws ServletException, IOException
 129    {
 130       ServletOutputStream out = response.getOutputStream();
 131
 132       response.setHeader("Cache-Control", "no-cache");
 133       response.setHeader("Pragma", "no-cache");
 134       response.setHeader("Expires", "0");
 135       System.out.println("UWOBO "+request.getPathInfo());
 136
 137       try {
 138          final String cmd = request.getPathInfo();
 139          if (cmd == null) {
 140             sendError(response, out, "unknown command", help); return;
 141          }
 142          if (cmd.equals("/add")) {
 143             final String[] xslkey = request.getParameterValues("key");
 144             if (xslkey == null) {
 145                sendError(response, out, "bad parameters", usage[1]); return;
 146             }
 147             html_open(response, out);
 148             for (int i = 0; i < xslkey.length; i++) {
 149                final String data[] = split2(xslkey[i], ",");
 150                out.println(msg_out("adding key "+data[0]+" ("+data[1]+")"));
 151                try {
 152                   server.add(data[1], data[0]);
 153                 } catch (TransformerConfigurationException tce) {
 154                   out.println(exc_out("stylesheet error", tce));
 155                } catch (Exception e) {
 156                   out.println(exc_out(null, e));
 157                }
 158             }
 159             html_close(out); return;
 160          }
 161          if (cmd.equals("/apply")) {
 162             final String infile = request.getParameter("xmluri");
 163             final String keys = request.getParameter("keys");
 164
 165             if (infile == null || keys == null) {
 166                sendError(response, out, "bad parameters", usage[6]); return;
 167             }
 168
 169             final String[] keyName = split(keys, ",");
 170             final Key[] keySeq = new Key[keyName.length];
 171             for (int i = 0; i < keySeq.length; i++) {
 172                keySeq[i] = new Key();
 173                keySeq[i].name = keyName[i];
 174                keySeq[i].params = new HashMap();
 175             }
 176
 177             final Properties props = new Properties();
 178             final Enumeration e = request.getParameterNames();
 179             while (e.hasMoreElements()) {
 180                String param = (String) e.nextElement();
 181                if (param.startsWith("param.")) {
 182                   final String name = param.substring(6);
 183                   final String value = request.getParameter(param);
 184                   final String[] keyParam = split(name, ".");
 185                   if (keyParam.length == 1) {
 186                      // this is a global parameter
 187                      Server.log("global parameter: " + keyParam[0] + " = " + value);
 188                      for (int i = 0; i < keySeq.length; i++)
 189                         // we add the global parameter only if there is no
 190                         // local parameter with the same name
 191                         if (!keySeq[i].params.containsKey(keyParam[0]))
 192                            keySeq[i].params.put(keyParam[0], value);
 193                   } else
 194                   if (keyParam.length == 2) {
 195                      // this is a local parameter
 196                      Server.log("local parameter: " + keyParam[0] + "." + keyParam[1] + " = " + value);
 197                      for (int i = 0; i < keySeq.length; i++) {
 198                         if (keySeq[i].name.equals(keyParam[0]))
 199                            keySeq[i].params.put(keyParam[1], value);
 200                      }
 201                   } else {
 202                      sendError(response, out, "bad parameters", usage[6]); return;
 203                   }
 204                } else
 205                if (param.startsWith("prop.")) {
 206                   final String name = param.substring(5);
 207                   final String value = request.getParameter(param);
 208                   Server.log("property: " + name + " = " + value);
 209                   props.setProperty(name, value);
 210                }
 211             }
 212
 213             String contentType = props.getProperty(OutputKeys.MEDIA_TYPE);
 214             if (contentType == null && keySeq.length > 0)
 215                contentType = server.getContentType(keySeq[keySeq.length - 1].name);
 216             else if (contentType == null)
 217                contentType = "text/xml";
 218             response.setContentType(contentType);
 219             Server.log("content type: " + contentType);
 220
 221             try {
 222                out = response.getOutputStream();
 223                server.apply(infile, out, keySeq, props);
 224                out.close();
 225             } catch (TransformerConfigurationException tce) {
 226                sendError(response, out, exc_out("stylesheet error", tce), "");
 227             } catch (Exception ee) {
 228                sendError(response, out, exc_out(null, ee), "");
 229             }
 230             return;
 231          }
 232          if (cmd.equals("/remove")) {
 233             final String key = request.getParameter("keys");
 234             final String [] data = split(key, ",");
 235             html_open(response, out);
 236             for (int i = 0; i < data.length; i++) {
 237                if (data[i] == null) {
 238                   out.println(msg_out("removing all keys"));
 239                   server.removeAll();
 240                } else {
 241                   out.println(msg_out("removing key "+data[i]));
 242                   server.remove(data[i]);
 243                }
 244             }
 245             html_close(out); return;
 246          }
 247          if (cmd.equals("/list")) {
 248             html_open(response, out);
 249             out.println("<p>stylesheet list:</p><ul>");
 250
 251             Iterator i = server.list().iterator();
 252             while (i.hasNext())
 253                out.println("<li>"+i.next()+"</li>");
 254             out.println("</ul>"); html_close(out); return;
 255          }
 256          if (cmd.equals("/reload")) {
 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                try {
 262                   if (data[i] == null) {
 263                      out.println(msg_out("reloading all keys"));
 264                      server.reloadAll();
 265                   } else {
 266                      out.println(msg_out("reloading key "+data[i]));
 267                      server.reload(data[i]);
 268                   }
 269                } catch (TransformerConfigurationException tce) {
 270                   out.println(exc_out("stylesheet error", tce));
 271                } catch (Exception e) {
 272                   out.println(exc_out(null, e));
 273                }
 274             }
 275             html_close(out); return;
 276          }
 277          if (cmd.equals("/update")) {
 278             final String key = request.getParameter("keys");
 279             final String [] data = split(key, ",");
 280             html_open(response, out);
 281             for (int i = 0; i < data.length; i++) {
 282                try {
 283                   if (data[i] == null) {
 284                      out.println(msg_out("updating all keys"));
 285                      server.updateAll();
 286                   } else {
 287                      out.println(msg_out("updating key "+data[i]));
 288                      server.update(data[i]);
 289                   }
 290                } catch (TransformerConfigurationException tce) {
 291                   out.println(exc_out("stylesheet error", tce));
 292                } catch (Exception e) {
 293                   out.println(exc_out(null, e));
 294                }
 295             }
 296             html_close(out); return;
 297          }
 298          if (cmd.equals("/help")) {
 299             html_open(response, out);
 300             out.println("<h2>"+server.PACKAGE+" servlet - version "+server.VERSION+"</h1>");
 301             out.println("<b>compiled "+server.DATE+" at "+server.TIME.substring(0,2)+":"+server.TIME.substring(2)+"</b>");
 302             out.println("<p>usage:</p>"+help+"</body></html>");
 303             html_close(out); return;
 304          }
 305          sendError(response, out, "unknown command", help); return;
 306       } catch (Exception e) {
 307          sendError(response, out, exc_out(null, e),""); // FG: non dovrebbe servire mai
 308          return;
 309       }
 310    }
 311
 312    private void sendError(HttpServletResponse resp, ServletOutputStream out,
 313                           String msg, String usage)
 314    throws IOException
 315    {
 316       html_open(resp, out);
 317       out.println("<p>"+msg+"</p>usage: "+usage);
 318       html_close(out);
 319    }
 320
 321    public String getServletInfo()
 322    {
 323       return "The UWOBO servlet";
 324    }
 325 }