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 Riccardo Solmi
  44 */
  45 public class Servlet extends HttpServlet {
  46         public static final String[] usage = {
  47                 "http://<i>hostname</i>/helm/servlet/uwobo/help",
  48                 "http://<i>hostname</i>/helm/servlet/uwobo/add?xsluri=<i>stylesheet</i>&key=<i>name</i>",
  49                 "http://<i>hostname</i>/helm/servlet/uwobo/remove[?key=<i>name</i>]",
  50                 "http://<i>hostname</i>/helm/servlet/uwobo/list",
  51                 "http://<i>hostname</i>/helm/servlet/uwobo/reload[?key=<i>name</i>]",
  52                 "http://<i>hostname</i>/helm/servlet/uwobo/update[?key=<i>name</i>]",
  53                 "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>]*"
  54         };
  55         public static final String help;
  56
  57         static {
  58                 StringBuffer sb = new StringBuffer();
  59                 sb.append("<ul>");
  60                 for (int i=0; i<usage.length; i++)
  61                         sb.append("<li>").append(usage[i]).append("</li>");
  62                 sb.append("</ul>");
  63                 help = sb.toString();
  64         }
  65
  66         private Server server;
  67
  68         public void init(ServletConfig config) throws ServletException
  69         {
  70                 super.init(config);
  71
  72                 System.out.println("UWOBO init");
  73                 server = new Server();
  74         }
  75
  76         public static String[] split(final String s, final String delim)
  77         {
  78                 StringTokenizer st = new StringTokenizer(s, delim);
  79                 String[] res = new String[st.countTokens()];
  80                 for (int i = 0; i < res.length; i++) res[i] = st.nextToken();
  81                 return res;
  82         }
  83
  84         public void doGet(HttpServletRequest request, HttpServletResponse response)
  85         throws ServletException, IOException
  86         {
  87                 System.out.println("UWOBO "+request.getPathInfo());
  88                 ServletOutputStream out;
  89
  90                 try {
  91                         final String cmd = request.getPathInfo();
  92                         if (cmd == null) {
  93                                 sendError(response, HttpServletResponse.SC_NOT_FOUND, "unknown command", help);
  94                                 return;
  95                         }
  96                         if (cmd.equals("/add")) {
  97                                 final String filename = request.getParameter("xsluri");
  98                                 if (filename == null) {
  99                                         sendError(response, HttpServletResponse.SC_BAD_REQUEST, "bad parameters", usage[1]);
 100                                         return;
 101                                 }
 102                                 final String key = request.getParameter("key");
 103                                 server.add(filename, key);
 104                         } else if (cmd.equals("/apply")) {
 105                                 final String infile = request.getParameter("xmluri");
 106                                 final String keys = request.getParameter("keys");
 107
 108                                 if (infile == null || keys == null) {
 109                                         sendError(response, HttpServletResponse.SC_BAD_REQUEST, "bad parameters", usage[6]);
 110                                         return;
 111                                 }
 112
 113                                 final String[] keyName = split(keys, ",");
 114                                 final Key[] keySeq = new Key[keyName.length];
 115                                 for (int i = 0; i < keySeq.length; i++) {
 116                                         keySeq[i] = new Key();
 117                                         keySeq[i].name = keyName[i];
 118                                         keySeq[i].params = new HashMap();
 119                                 }
 120
 121                                 final Properties props = new Properties();
 122                                 final Enumeration e = request.getParameterNames();
 123                                 while (e.hasMoreElements()) {
 124                                         String param = (String) e.nextElement();
 125                                         if (param.startsWith("param.")) {
 126                                                 final String name = param.substring(6);
 127                                                 final String value = request.getParameter(param);
 128                                                 final String[] keyParam = split(name, ".");
 129                                                 if (keyParam.length == 1) {
 130                                                         // this is a global parameter
 131                                                         Server.log("global parameter: " + keyParam[0] + " = " + value);
 132                                                         for (int i = 0; i < keySeq.length; i++)
 133                                                                 // we add the global parameter only if there is no
 134                                                                 // local parameter with the same name
 135                                                                 if (!keySeq[i].params.containsKey(keyParam[0]))
 136                                                                         keySeq[i].params.put(keyParam[0], value);
 137                                                 } else if (keyParam.length == 2) {
 138                                                         // this is a local parameter
 139                                                         Server.log("local parameter: " + keyParam[0] + "." + keyParam[1] + " = " + value);
 140                                                         for (int i = 0; i < keySeq.length; i++) {
 141                                                                 if (keySeq[i].name.equals(keyParam[0]))
 142                                                                         keySeq[i].params.put(keyParam[1], value);
 143                                                         }
 144                                                 } else {
 145                                                         sendError(response, HttpServletResponse.SC_BAD_REQUEST, "bad parameters", usage[6]);
 146                                                         return;
 147                                                 }
 148                                         } else if (param.startsWith("prop.")) {
 149                                                 final String name = param.substring(5);
 150                                                 final String value = request.getParameter(param);
 151                                                 Server.log("property: " + name + " = " + value);
 152                                                 props.setProperty(name, value);
 153                                         }
 154                                 }
 155
 156                                 String contentType = props.getProperty(OutputKeys.MEDIA_TYPE);
 157                                 if (contentType == null && keySeq.length > 0)
 158                                         contentType = server.getContentType(keySeq[keySeq.length - 1].name);
 159                                 else if (contentType == null)
 160                                         contentType = "text/xml";
 161                                 response.setContentType(contentType);
 162                                 Server.log("content type: " + contentType);
 163
 164                                 out = response.getOutputStream();
 165                                 server.apply(infile, out, keySeq, props);
 166                                 out.close();
 167                                 return;
 168                         } else if (cmd.equals("/remove")) {
 169                                 final String key = request.getParameter("key");
 170                                 if (key == null)
 171                                         server.removeAll();
 172                                 else
 173                                         server.remove(key);
 174                         } else if (cmd.equals("/list")) {
 175                                 Iterator i = server.list().iterator();
 176
 177                                 response.setContentType("text/html");
 178                                 out = response.getOutputStream();
 179                                 out.println("<html><body><h1>Uwobo servlet</h1><p>stylesheet list:</p><ul>");
 180                                 while (i.hasNext())
 181                                         out.println("<li>"+i.next()+"</li>");
 182                                 out.println("</ul></body></html>");
 183                                 out.close();
 184                                 return;
 185                         } else if (cmd.equals("/reload")) {
 186                                 final String key = request.getParameter("key");
 187                                 if (key == null)
 188                                         server.reloadAll();
 189                                 else
 190                                         server.reload(key);
 191                         } else if (cmd.equals("/update")) {
 192                                 final String key = request.getParameter("key");
 193                                 if (key == null)
 194                                         server.updateAll();
 195                                 else
 196                                         server.update(key);
 197                         } else if (cmd.equals("/help")) {
 198                                 response.setContentType("text/html");
 199                                 out = response.getOutputStream();
 200                                 out.println("<html><body><h1>"+server.PACKAGE+" servlet - version "+server.VERSION+"</h1>");
 201                                 out.println("<b>compiled "+server.DATE+" at "+server.TIME.substring(0,2)+":"+server.TIME.substring(2)+"</b>");
 202                                 out.println("<p>usage:</p>"+help+"</body></html>");
 203                                 out.close();
 204                                 return;
 205                         } else {
 206                                 sendError(response, HttpServletResponse.SC_NOT_FOUND, "unknown command", help);
 207                                 return;
 208                         }
 209                 } catch (TransformerConfigurationException tce) {
 210                         sendError(response, HttpServletResponse.SC_BAD_REQUEST, "stylesheet error", tce);
 211                         return;
 212                 } catch (SAXException se) {
 213                         sendError(response, HttpServletResponse.SC_BAD_REQUEST, "SAX Exception", se);
 214                         return;
 215                 } catch (Exception e) {
 216                         sendError(response, HttpServletResponse.SC_BAD_REQUEST, "exception", e);
 217                         return;
 218                 }
 219
 220                 response.setContentType("text/html");
 221                 response.setHeader("Cache-Control", "no-cache");
 222                 response.setHeader("Pragma", "no-cache");
 223                 response.setHeader("Expires", "0");
 224                 out = response.getOutputStream();
 225                 out.println("<html><body><h1>Uwobo servlet</h1><p>done</p></body></html>");
 226                 out.close();
 227         }
 228
 229         private void sendError(HttpServletResponse response, int code, String msg, Exception e) throws IOException {
 230                 String err;
 231                 if (e != null)
 232                         err = "<p>"+e.getMessage()+"</P>";
 233                 else
 234                         err = "";
 235                 response.setContentType("text/html");
 236                 response.sendError(code, "<html><body><h1>Uwobo servlet</h1><p>"+msg+"</p>"+err+"</body></html>");
 237         }
 238
 239         private void sendError(HttpServletResponse response, int code, String msg, String usage) throws IOException {
 240                 response.setContentType("text/html");
 241                 response.sendError(code, "<html><body><h1>Uwobo servlet</h1><p>"+msg+"</p>usage: "+usage+"</body></html>");
 242         }
 243
 244         public String getServletInfo() {
 245                 return "The UWOBO servlet";
 246         }
 247 }