| Classes in this File | Line Coverage | Branch Coverage | Complexity | ||||
| PoemServlet |
|
| 3.6666666666666665;3.667 | ||||
| PoemServlet$1 |
|
| 3.6666666666666665;3.667 |
| 1 | /* | |
| 2 | * $Source: /usr/cvsroot/melati/melati/src/site/resources/withWebmacro/org.melati.servlet.PoemServlet.html,v $ | |
| 3 | * $Revision: 1.1 $ | |
| 4 | * | |
| 5 | * Copyright (C) 2000 Tim Joyce | |
| 6 | * | |
| 7 | * Part of Melati (http://melati.org), a framework for the rapid | |
| 8 | * development of clean, maintainable web applications. | |
| 9 | * | |
| 10 | * Melati is free software; Permission is granted to copy, distribute | |
| 11 | * and/or modify this software under the terms either: | |
| 12 | * | |
| 13 | * a) the GNU General Public License as published by the Free Software | |
| 14 | * Foundation; either version 2 of the License, or (at your option) | |
| 15 | * any later version, | |
| 16 | * | |
| 17 | * or | |
| 18 | * | |
| 19 | * b) any version of the Melati Software License, as published | |
| 20 | * at http://melati.org | |
| 21 | * | |
| 22 | * You should have received a copy of the GNU General Public License and | |
| 23 | * the Melati Software License along with this program; | |
| 24 | * if not, write to the Free Software Foundation, Inc., | |
| 25 | * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA to obtain the | |
| 26 | * GNU General Public License and visit http://melati.org to obtain the | |
| 27 | * Melati Software License. | |
| 28 | * | |
| 29 | * Feel free to contact the Developers of Melati (http://melati.org), | |
| 30 | * if you would like to work out a different arrangement than the options | |
| 31 | * outlined here. It is our intention to allow Melati to be used by as | |
| 32 | * wide an audience as possible. | |
| 33 | * | |
| 34 | * This program is distributed in the hope that it will be useful, | |
| 35 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | |
| 36 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
| 37 | * GNU General Public License for more details. | |
| 38 | * | |
| 39 | * Contact details for copyright holder: | |
| 40 | * | |
| 41 | * Tim Joyce <timj At paneris.org> | |
| 42 | * http://paneris.org/ | |
| 43 | * 68 Sandbanks Rd, Poole, Dorset. BH14 8BY. UK | |
| 44 | */ | |
| 45 | ||
| 46 | package org.melati.servlet; | |
| 47 | ||
| 48 | import java.io.IOException; | |
| 49 | ||
| 50 | import javax.servlet.ServletException; | |
| 51 | import javax.servlet.http.HttpServletRequest; | |
| 52 | ||
| 53 | import org.melati.Melati; | |
| 54 | import org.melati.PoemContext; | |
| 55 | import org.melati.poem.AccessPoemException; | |
| 56 | import org.melati.poem.Field; | |
| 57 | import org.melati.poem.NoSuchColumnPoemException; | |
| 58 | import org.melati.poem.PoemThread; | |
| 59 | import org.melati.poem.PoemTask; | |
| 60 | import org.melati.poem.AccessToken; | |
| 61 | import org.melati.poem.util.StringUtils; | |
| 62 | ||
| 63 | /** | |
| 64 | * Base class to use Poem with Servlets. | |
| 65 | * <p> | |
| 66 | * Simply extend this class and override the doPoemRequest method. If you are | |
| 67 | * going to use a template engine look at TemplateServlet. | |
| 68 | * <UL> | |
| 69 | * <LI> <A NAME=pathinfoscan>By default, the path info of the URL by which the | |
| 70 | * servlet was called up is examined to determine the `logical name' of the | |
| 71 | * Melati POEM database to which the servlet should connect, and possibly a | |
| 72 | * table within that database, an object within that table, and a `method' to | |
| 73 | * apply to that object.</A> The URL is expected to take one of the following | |
| 74 | * forms: <BLOCKQUOTE><TT> http://<I>h</I>/<I>s</I>/<I>db</I>/ <BR> | |
| 75 | * http://<I>h</I>/<I>s</I>/<I>db</I>/<I>meth</I> <BR> | |
| 76 | * http://<I>h</I>/<I>s</I>/<I>db</I>/<I>tbl</I>/<I>meth</I> <BR> | |
| 77 | * http://<I>h</I>/<I>s</I>/<I>db</I>/<I>tbl</I>/<I>troid</I>/<I>meth</I> | |
| 78 | * <BR> | |
| 79 | * http://<I>h</I>/<I>s</I>/<I>db</I>/<I>tbl</I>/<I>troid</I>/<I>meth</I>/<I>other</I> | |
| 80 | * </TT></BLOCKQUOTE> and the following components are broken out of the path | |
| 81 | * info and passed to your application code in the <TT>melati</TT> parameter | |
| 82 | * (which is also copied automatically into <TT>context</TT> so that it is | |
| 83 | * easily available in templates): | |
| 84 | * <TABLE> | |
| 85 | * <TR> | |
| 86 | * <TD><TT><I>h</I></TT></TD> | |
| 87 | * <TD>host name, such as <TT>www.melati.org</TT></TD> | |
| 88 | * </TR> | |
| 89 | * <TR> | |
| 90 | * <TD><TT><I>s</I></TT></TD> | |
| 91 | * <TD> servlet-determining part, such as <TT>melati/org.melati.admin.Admin</TT> | |
| 92 | * </TD> | |
| 93 | * </TR> | |
| 94 | * <TR> | |
| 95 | * <TD><TT><I>db</I></TT></TD> | |
| 96 | * <TD> The first element of the path info is taken to be the `logical name' of | |
| 97 | * the Melati POEM database to which the servlet should connect. It is mapped | |
| 98 | * onto JDBC connection details via the config file <TT>org.melati.LogicalDatabase.properties</TT>, | |
| 99 | * of which there is an example in the source tree. This is automatically made | |
| 100 | * available in templates as <TT>$melati.Database</TT>. </TD> | |
| 101 | * <TR> | |
| 102 | * <TD><TT><I>tbl</I></TT></TD> | |
| 103 | * <TD> The DBMS name of a table with which the servlet is concerned: perhaps it | |
| 104 | * is meant to list its contents. This is automatically made available in | |
| 105 | * templates as <TT>$melati.Table</TT>. </TD> | |
| 106 | * </TR> | |
| 107 | * <TR> | |
| 108 | * <TD><TT><I>troid</I></TT></TD> | |
| 109 | * <TD> The POEM `troid' (table row identifier, or row-unique integer) of a row | |
| 110 | * within <TT><I>tbl</I></TT> with which the servlet is concerned: perhaps it | |
| 111 | * is meant to display it. This is automatically made available in templates as | |
| 112 | * <TT>$melati.Object</TT>. </TD> | |
| 113 | * </TR> | |
| 114 | * <TR> | |
| 115 | * <TD><TT><I>meth</I></TT></TD> | |
| 116 | * <TD> A freeform string telling your servlet what it is meant to do. This is | |
| 117 | * automatically made available in templates as <TT>$melati.Method</TT>. | |
| 118 | * </TD> | |
| 119 | * </TR> | |
| 120 | * <TR> | |
| 121 | * <TD><TT><I>other</I></TT></TD> | |
| 122 | * <TD> Any other information you wish to put in the pathinfo. This is useful, | |
| 123 | * for instance, if you wish to specify the "filename" of your | |
| 124 | * servlet. For instance, if you call <TT>/db/myfiles/0/Download/afile.html</TT> | |
| 125 | * and return a stream with a content-type of <tt>application/octet-stream</tt> | |
| 126 | * most browsers will prompt you to save the "file" as | |
| 127 | * <tt>afile.html</tt> </TD> | |
| 128 | * </TR> | |
| 129 | * </TABLE> | |
| 130 | * <LI> You can change the way these things are determined by overriding <TT>poemContext</TT>. | |
| 131 | * <LI> Any POEM database operations you perform will be done with the access | |
| 132 | * rights of the POEM <TT>User</TT> associated with the servlet session. If | |
| 133 | * there is no established servlet session, the current user will be set to the | |
| 134 | * default `guest' user. If this method terminates with an <TT>AccessPoemException</TT>, | |
| 135 | * indicating that you have attempted something which you aren't entitled to do, | |
| 136 | * the user will be prompted to log in, and the original request will be | |
| 137 | * retried. The precise mechanism used for login is <A | |
| 138 | * HREF=#loginmechanism>configurable</A>. | |
| 139 | * <LI> | |
| 140 | * No changes made to the database by other concurrently executing threads | |
| 141 | * will be visible to you (in the sense that once you have seen a particular | |
| 142 | * version of a record, you will always subsequently see the same one), and your | |
| 143 | * own changes will not be made permanent until this method completes | |
| 144 | * successfully or you perform an explicit <TT>PoemThread.commit()</TT>. If | |
| 145 | * it terminates with an exception or you issue a <TT>PoemThread.rollback()</TT>, | |
| 146 | * your changes will be lost. | |
| 147 | * <LI> <A NAME=loginmechanism> | |
| 148 | * It's possible to configure how your <TT>PoemServlet</TT>-derived | |
| 149 | * servlets implement user login.</A> If the properties file <TT><A | |
| 150 | * HREF=../org.melati.MelatiConfig.properties> | |
| 151 | * org.melati.MelatiConfig.properties</A></TT> exists and contains a setting | |
| 152 | * <TT>org.melati.MelatiConfig.accessHandler=<I>foo</I></TT>, then <TT><I>foo</I></TT> | |
| 153 | * is taken to be the name of a class implementing the <TT>AccessHandler</TT> | |
| 154 | * interface. The default is <TT>HttpSessionAccessHandler</TT>, which stores | |
| 155 | * the user id in the servlet session, and redirects to the <TT>Login</TT> | |
| 156 | * servlet to throw up templated login screens. If instead you specify | |
| 157 | * <TT>HttpBasicAuthenticationAccessHandler</TT>, the user id is maintained | |
| 158 | * using HTTP Basic Authentication (RFC2068 11.1, the | |
| 159 | * mechanism commonly used to password-protect static pages), and the task of | |
| 160 | * popping up login dialogs is delegated to the browser. The advantage of the | |
| 161 | * former method is that the user gets a more informative interface which is | |
| 162 | * more under the designer's control; the advantage of the latter method is that | |
| 163 | * no cookies or URL rewriting are required---for instance it is probably more | |
| 164 | * appropriate for WAP phones. Both methods involve sending the user's password | |
| 165 | * in plain text across the public network. | |
| 166 | * </UL> | |
| 167 | * | |
| 168 | * @see org.melati.poem.Database#guestAccessToken | |
| 169 | * @see org.melati.poem.PoemThread#commit | |
| 170 | * @see org.melati.poem.PoemThread#rollback | |
| 171 | * @see #poemContext | |
| 172 | * @see org.melati.login.AccessHandler | |
| 173 | * @see org.melati.login.HttpSessionAccessHandler | |
| 174 | * @see org.melati.login.Login | |
| 175 | * @see org.melati.login.HttpBasicAuthenticationAccessHandler | |
| 176 | */ | |
| 177 | ||
| 178 | 56 | public abstract class PoemServlet extends ConfigServlet { |
| 179 | ||
| 180 | /** | |
| 181 | * Eclipse generated. | |
| 182 | */ | |
| 183 | private static final long serialVersionUID = 7694978400584943446L; | |
| 184 | ||
| 185 | /** | |
| 186 | * A place to do things before entering the session | |
| 187 | * of the user, here is a good place to use root access token. | |
| 188 | * | |
| 189 | * Overriden in TemplateServlet. | |
| 190 | * | |
| 191 | * @param melati | |
| 192 | * org.melati.Melati A source of information about the Melati | |
| 193 | * database context (database, table, object) and utility objects | |
| 194 | * such as error handlers. | |
| 195 | */ | |
| 196 | ||
| 197 | protected void prePoemSession(Melati melati) throws Exception { | |
| 198 | 2 | } |
| 199 | ||
| 200 | /** | |
| 201 | * @see javax.servlet.Servlet#destroy() | |
| 202 | */ | |
| 203 | public void destroy() { | |
| 204 | 30 | super.destroy(); |
| 205 | 30 | } |
| 206 | ||
| 207 | /** | |
| 208 | * Process the request. | |
| 209 | */ | |
| 210 | ||
| 211 | protected void doConfiguredRequest(final Melati melati) | |
| 212 | throws ServletException, IOException { | |
| 213 | ||
| 214 | // Set up a POEM session and call the application code | |
| 215 | ||
| 216 | // Do something outside of the PoemSession | |
| 217 | try { | |
| 218 | 1121 | melati.getConfig().getAccessHandler().buildRequest(melati); |
| 219 | 1121 | prePoemSession(melati); |
| 220 | 0 | } catch (Exception e) { |
| 221 | // we have to log this here, otherwise we lose the stacktrace | |
| 222 | 0 | error(melati, e); |
| 223 | 0 | throw new TrappedException("Problem in prePoemSession", e); |
| 224 | 1121 | } |
| 225 | ||
| 226 | 1121 | final PoemServlet _this = this; |
| 227 | ||
| 228 | 1121 | melati.getDatabase().inSession(AccessToken.root, new PoemTask() { |
| 229 | public void run() { | |
| 230 | 1121 | String poemAdministratorsName = null; |
| 231 | 1121 | String poemAdministratorsEmail = null; |
| 232 | ||
| 233 | try { | |
| 234 | try { | |
| 235 | 1121 | poemAdministratorsName = melati.getDatabase().administratorUser().getName(); |
| 236 | 1121 | Field emailField = null; |
| 237 | try { | |
| 238 | 1121 | emailField = melati.getDatabase().administratorUser().getField("email"); |
| 239 | 982 | poemAdministratorsEmail = emailField.toString(); |
| 240 | 139 | } catch (NoSuchColumnPoemException e) { |
| 241 | 139 | poemAdministratorsEmail = "noEmailDefined@nobody.com"; |
| 242 | 982 | } |
| 243 | 1121 | _this.setSysAdminName(poemAdministratorsName); |
| 244 | 1121 | _this.setSysAdminEmail(poemAdministratorsEmail); |
| 245 | ||
| 246 | 0 | } catch (Exception e) { |
| 247 | 0 | _handleException(melati, e); |
| 248 | 1121 | } |
| 249 | 0 | } catch (Exception e) { |
| 250 | // we have to log this here, otherwise we lose the stacktrace | |
| 251 | 0 | error(melati, e); |
| 252 | 0 | throw new TrappedException(e); |
| 253 | 1121 | } |
| 254 | ||
| 255 | ||
| 256 | 1121 | melati.getConfig().getAccessHandler().establishUser(melati); |
| 257 | 1121 | melati.loadTableAndObject(); |
| 258 | ||
| 259 | try { | |
| 260 | try { | |
| 261 | 1121 | _this.doPoemRequest(melati); |
| 262 | 34 | } catch (Exception e) { |
| 263 | 34 | _handleException(melati, e); |
| 264 | 1087 | } |
| 265 | 18 | } catch (Exception e) { |
| 266 | // we have to log this here, otherwise we lose the stacktrace | |
| 267 | 18 | error(melati, e); |
| 268 | 18 | throw new TrappedException(e); |
| 269 | 1103 | } |
| 270 | 1103 | } |
| 271 | ||
| 272 | public String toString() { | |
| 273 | 0 | HttpServletRequest request = melati.getRequest(); |
| 274 | 0 | return "PoemServlet: " |
| 275 | + ((request == null) ? "(no request present)" : request | |
| 276 | .getRequestURI()); | |
| 277 | } | |
| 278 | }); | |
| 279 | 1103 | } |
| 280 | ||
| 281 | /** | |
| 282 | * Override this to provide a different administrator's details to the | |
| 283 | * database admin user. | |
| 284 | * | |
| 285 | * @return the System Administrators name. | |
| 286 | */ | |
| 287 | public String getSysAdminName() { | |
| 288 | 28 | return sysAdminName; |
| 289 | } | |
| 290 | ||
| 291 | /** | |
| 292 | * Override this to provide a different administrator's details to the | |
| 293 | * database admin user. | |
| 294 | * | |
| 295 | * @return the System Administrators email address. | |
| 296 | */ | |
| 297 | public String getSysAdminEmail() { | |
| 298 | 28 | return sysAdminEmail; |
| 299 | } | |
| 300 | ||
| 301 | /** | |
| 302 | * Default method to handle an exception without a template engine. | |
| 303 | * | |
| 304 | * @param melati | |
| 305 | * the Melati | |
| 306 | * @param exception | |
| 307 | * the exception to handle | |
| 308 | */ | |
| 309 | protected void handleException(Melati melati, Exception exception) | |
| 310 | throws Exception { | |
| 311 | ||
| 312 | 34 | if (exception instanceof AccessPoemException) { |
| 313 | 16 | melati.getConfig().getAccessHandler().handleAccessException(melati, |
| 314 | (AccessPoemException) exception); | |
| 315 | } else | |
| 316 | 18 | throw exception; |
| 317 | 16 | } |
| 318 | ||
| 319 | protected final void _handleException(Melati melati, Exception exception) | |
| 320 | throws Exception { | |
| 321 | try { | |
| 322 | 34 | handleException(melati, exception); |
| 323 | 18 | } catch (Exception e) { |
| 324 | 18 | PoemThread.rollback(); |
| 325 | 18 | throw e; |
| 326 | 16 | } |
| 327 | 16 | } |
| 328 | ||
| 329 | protected PoemContext poemContext(Melati melati) throws PathInfoException { | |
| 330 | ||
| 331 | 1103 | PoemContext it = new PoemContext(); |
| 332 | ||
| 333 | 1103 | String initParameterPathInfo = getInitParameter("pathInfo"); |
| 334 | String[] parts; | |
| 335 | 1103 | if (initParameterPathInfo != null) |
| 336 | 6 | parts = StringUtils.split(initParameterPathInfo, '/'); |
| 337 | else | |
| 338 | 1097 | parts = melati.getPathInfoParts(); |
| 339 | ||
| 340 | // set it to something in order to provoke meaningful error | |
| 341 | 1103 | it.setLogicalDatabase(""); |
| 342 | 1103 | if (parts.length > 0) { |
| 343 | 1097 | it.setLogicalDatabase(parts[0]); |
| 344 | 1097 | if (parts.length == 2) |
| 345 | 165 | it.setMethod(parts[1]); |
| 346 | 1097 | if (parts.length == 3) { |
| 347 | 696 | it.setTable(parts[1]); |
| 348 | 696 | it.setMethod(parts[2]); |
| 349 | } | |
| 350 | 1097 | if (parts.length >= 4) { |
| 351 | 156 | it.setTable(parts[1]); |
| 352 | try { | |
| 353 | 156 | it.setTroid(new Integer(parts[2])); |
| 354 | 0 | } catch (NumberFormatException e) { |
| 355 | 0 | throw new PathInfoException(melati.getRequest().getPathInfo(), e); |
| 356 | 156 | } |
| 357 | 156 | if (parts.length == 4) { |
| 358 | 154 | it.setMethod(parts[3]); |
| 359 | } else { | |
| 360 | 2 | String pathInfo = melati.getRequest().getPathInfo(); |
| 361 | 2 | pathInfo = pathInfo.substring(1); |
| 362 | 8 | for (int i = 0; i < 3; i++) { |
| 363 | 6 | pathInfo = pathInfo.substring(pathInfo.indexOf("/") + 1); |
| 364 | } | |
| 365 | 2 | it.setMethod(pathInfo); |
| 366 | } | |
| 367 | } | |
| 368 | } | |
| 369 | 1103 | return it; |
| 370 | } | |
| 371 | ||
| 372 | /* | |
| 373 | * This is provided for convenience, so you don't have to specify the | |
| 374 | * logicaldatabase on the pathinfo. This is a very good idea when writing your | |
| 375 | * applications where you are typically only accessing a single database. | |
| 376 | * Simply override poemContext(Melati melati) thus: | |
| 377 | * <code> | |
| 378 | * protected PoemContext poemContext(Melati melati) throws PathInfoException { | |
| 379 | * return poemContextWithLDB(melati,"<your logical database name>"); | |
| 380 | * } | |
| 381 | * </code> | |
| 382 | */ | |
| 383 | protected PoemContext poemContextWithLDB(Melati melati, String logicalDatabase) | |
| 384 | throws PathInfoException { | |
| 385 | 24 | PoemContext it = new PoemContext(); |
| 386 | 24 | String initParameterPathInfo = getInitParameter("pathInfo"); |
| 387 | String[] parts; | |
| 388 | 24 | if (initParameterPathInfo != null) |
| 389 | 0 | parts = StringUtils.split(initParameterPathInfo, '/'); |
| 390 | else | |
| 391 | 24 | parts = melati.getPathInfoParts(); |
| 392 | ||
| 393 | // set it to something in order to provoke meaningful error | |
| 394 | 24 | it.setLogicalDatabase(logicalDatabase); |
| 395 | 24 | if (parts.length > 0) { |
| 396 | 2 | if (parts.length == 1) |
| 397 | 2 | it.setMethod(parts[0]); |
| 398 | 2 | if (parts.length == 2) { |
| 399 | 0 | it.setTable(parts[0]); |
| 400 | 0 | it.setMethod(parts[1]); |
| 401 | } | |
| 402 | 2 | if (parts.length >= 3) { |
| 403 | 0 | it.setTable(parts[0]); |
| 404 | 0 | it.setMethod(parts[2]); |
| 405 | try { | |
| 406 | 0 | it.setTroid(new Integer(parts[1])); |
| 407 | 0 | } catch (NumberFormatException e) { |
| 408 | 0 | throw new PathInfoException(melati.getRequest().getPathInfo(), e); |
| 409 | 0 | } |
| 410 | } | |
| 411 | 2 | if (parts.length == 3) { |
| 412 | 0 | it.setMethod(parts[2]); |
| 413 | } else { | |
| 414 | 2 | String pathInfo = melati.getRequest().getPathInfo(); |
| 415 | 2 | pathInfo = pathInfo.substring(1); |
| 416 | 6 | for (int i = 0; i < 2; i++) { |
| 417 | 4 | pathInfo = pathInfo.substring(pathInfo.indexOf("/") + 1); |
| 418 | } | |
| 419 | 2 | it.setMethod(pathInfo); |
| 420 | } | |
| 421 | ||
| 422 | } | |
| 423 | 24 | return it; |
| 424 | } | |
| 425 | ||
| 426 | /** | |
| 427 | * Override this method to build up your own output. | |
| 428 | * | |
| 429 | * @param melati | |
| 430 | */ | |
| 431 | protected abstract void doPoemRequest(Melati melati) throws Exception; | |
| 432 | ||
| 433 | } |