src/main/java/net/pterodactylus/sone/core/WebOfTrustUpdater.java

   1 /*
   2  * Sone - WebOfTrustUpdater.java - Copyright © 2012 David Roden
   3  *
   4  * This program is free software: you can redistribute it and/or modify
   5  * it under the terms of the GNU General Public License as published by
   6  * the Free Software Foundation, either version 3 of the License, or
   7  * (at your option) any later version.
   8  *
   9  * This program is distributed in the hope that it will be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12  * GNU General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU General Public License
  15  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  16  */
  17
  18 package net.pterodactylus.sone.core;
  19
  20 import java.util.concurrent.BlockingQueue;
  21 import java.util.concurrent.LinkedBlockingQueue;
  22 import java.util.logging.Level;
  23 import java.util.logging.Logger;
  24
  25 import net.pterodactylus.sone.freenet.plugin.PluginException;
  26 import net.pterodactylus.sone.freenet.wot.DefaultIdentity;
  27 import net.pterodactylus.sone.freenet.wot.Identity;
  28 import net.pterodactylus.sone.freenet.wot.OwnIdentity;
  29 import net.pterodactylus.sone.freenet.wot.Trust;
  30 import net.pterodactylus.sone.freenet.wot.WebOfTrustConnector;
  31 import net.pterodactylus.sone.freenet.wot.WebOfTrustException;
  32 import net.pterodactylus.util.logging.Logging;
  33 import net.pterodactylus.util.service.AbstractService;
  34 import net.pterodactylus.util.validation.Validation;
  35
  36 /**
  37  * Updates WebOfTrust identity data in a background thread because communicating
  38  * with the WebOfTrust plugin can potentially last quite long.
  39  *
  40  * @author <a href="mailto:bombe@pterodactylus.net">David ‘Bombe’ Roden</a>
  41  */
  42 public class WebOfTrustUpdater extends AbstractService {
  43
  44         /** The logger. */
  45         private static final Logger logger = Logging.getLogger(WebOfTrustUpdater.class);
  46
  47         /** Stop job. */
  48         @SuppressWarnings("synthetic-access")
  49         private final WebOfTrustUpdateJob stopJob = new WebOfTrustUpdateJob();
  50
  51         /** The web of trust connector. */
  52         private final WebOfTrustConnector webOfTrustConnector;
  53
  54         /** The queue for jobs. */
  55         private final BlockingQueue<WebOfTrustUpdateJob> updateJobs = new LinkedBlockingQueue<WebOfTrustUpdateJob>();
  56
  57         /**
  58          * Creates a new trust updater.
  59          *
  60          * @param webOfTrustConnector
  61          *            The web of trust connector
  62          */
  63         public WebOfTrustUpdater(WebOfTrustConnector webOfTrustConnector) {
  64                 super("Trust Updater");
  65                 this.webOfTrustConnector = webOfTrustConnector;
  66         }
  67
  68         //
  69         // ACTIONS
  70         //
  71
  72         /**
  73          * Retrieves the trust relation between the truster and the trustee. This
  74          * method will return immediately and perform a trust update in the
  75          * background.
  76          *
  77          * @param truster
  78          *            The identity giving the trust
  79          * @param trustee
  80          *            The identity receiving the trust
  81          */
  82         public void getTrust(OwnIdentity truster, Identity trustee) {
  83                 GetTrustJob getTrustJob = new GetTrustJob(truster, trustee);
  84                 if (!updateJobs.contains(getTrustJob)) {
  85                         logger.log(Level.FINER, "Adding Trust Update Job: " + getTrustJob);
  86                         try {
  87                                 updateJobs.put(getTrustJob);
  88                         } catch (InterruptedException ie1) {
  89                                 /* the queue is unbounded so it should never block. */
  90                         }
  91                 }
  92         }
  93
  94         /**
  95          * Updates the trust relation between the truster and the trustee. This
  96          * method will return immediately and perform a trust update in the
  97          * background.
  98          *
  99          * @param truster
 100          *            The identity giving the trust
 101          * @param trustee
 102          *            The identity receiving the trust
 103          * @param score
 104          *            The new level of trust (from -100 to 100, may be {@code null}
 105          *            to remove the trust completely)
 106          * @param comment
 107          *            The comment of the trust relation
 108          */
 109         public void setTrust(OwnIdentity truster, Identity trustee, Integer score, String comment) {
 110                 SetTrustJob setTrustJob = new SetTrustJob(truster, trustee, score, comment);
 111                 if (updateJobs.contains(setTrustJob)) {
 112                         updateJobs.remove(setTrustJob);
 113                 }
 114                 logger.log(Level.FINER, "Adding Trust Update Job: " + setTrustJob);
 115                 try {
 116                         updateJobs.put(setTrustJob);
 117                 } catch (InterruptedException e) {
 118                         /* the queue is unbounded so it should never block. */
 119                 }
 120         }
 121
 122         /**
 123          * Adds the given context to the given own identity.
 124          *
 125          * @param ownIdentity
 126          *            The own identity to add the context to
 127          * @param context
 128          *            The context to add
 129          */
 130         public void addContext(OwnIdentity ownIdentity, String context) {
 131                 addContextWait(ownIdentity, context, false);
 132         }
 133
 134         /**
 135          * Adds the given context to the given own identity, waiting for completion
 136          * of the operation.
 137          *
 138          * @param ownIdentity
 139          *            The own identity to add the context to
 140          * @param context
 141          *            The context to add
 142          * @return {@code true} if the context was added successfully, {@code false}
 143          *         otherwise
 144          */
 145         public boolean addContextWait(OwnIdentity ownIdentity, String context) {
 146                 return addContextWait(ownIdentity, context, true);
 147         }
 148
 149         /**
 150          * Adds the given context to the given own identity, waiting for completion
 151          * of the operation.
 152          *
 153          * @param ownIdentity
 154          *            The own identity to add the context to
 155          * @param context
 156          *            The context to add
 157          * @param wait
 158          *            {@code true} to wait for the end of the operation,
 159          *            {@code false} to return immediately
 160          * @return {@code true} if the context was added successfully, {@code false}
 161          *         if the context was not added successfully, or if the job should
 162          *         not wait for completion
 163          */
 164         private boolean addContextWait(OwnIdentity ownIdentity, String context, boolean wait) {
 165                 AddContextJob addContextJob = new AddContextJob(ownIdentity, context);
 166                 if (!updateJobs.contains(addContextJob)) {
 167                         logger.log(Level.FINER, "Adding Context Job: " + addContextJob);
 168                         try {
 169                                 updateJobs.put(addContextJob);
 170                         } catch (InterruptedException ie1) {
 171                                 /* the queue is unbounded so it should never block. */
 172                         }
 173                         if (wait) {
 174                                 return addContextJob.waitForCompletion();
 175                         }
 176                 } else if (wait) {
 177                         for (WebOfTrustUpdateJob updateJob : updateJobs) {
 178                                 if (updateJob.equals(addContextJob)) {
 179                                         return updateJob.waitForCompletion();
 180                                 }
 181                         }
 182                 }
 183                 return false;
 184         }
 185
 186         //
 187         // SERVICE METHODS
 188         //
 189
 190         /**
 191          * {@inheritDoc}
 192          */
 193         @Override
 194         protected void serviceRun() {
 195                 while (!shouldStop()) {
 196                         try {
 197                                 WebOfTrustUpdateJob updateJob = updateJobs.take();
 198                                 if (shouldStop() || (updateJob == stopJob)) {
 199                                         break;
 200                                 }
 201                                 logger.log(Level.FINE, "Running Trust Update Job: " + updateJob);
 202                                 long startTime = System.currentTimeMillis();
 203                                 updateJob.run();
 204                                 long endTime = System.currentTimeMillis();
 205                                 logger.log(Level.FINE, "Trust Update Job finished, took " + (endTime - startTime) + " ms.");
 206                         } catch (InterruptedException ie1) {
 207                                 /* happens, ignore, loop. */
 208                         }
 209                 }
 210         }
 211
 212         /**
 213          * {@inheritDoc}
 214          */
 215         @Override
 216         protected void serviceStop() {
 217                 try {
 218                         updateJobs.put(stopJob);
 219                 } catch (InterruptedException ie1) {
 220                         /* the queue is unbounded so it should never block. */
 221                 }
 222         }
 223
 224         /**
 225          * Base class for WebOfTrust update jobs.
 226          *
 227          * @author <a href="mailto:bombe@pterodactylus.net">David ‘Bombe’ Roden</a>
 228          */
 229         private class WebOfTrustUpdateJob {
 230
 231                 /** Object for synchronization. */
 232                 @SuppressWarnings("hiding")
 233                 private final Object syncObject = new Object();
 234
 235                 /** Whether the job has finished. */
 236                 private boolean finished;
 237
 238                 /** Whether the job was successful. */
 239                 private boolean success;
 240
 241                 //
 242                 // ACTIONS
 243                 //
 244
 245                 /**
 246                  * Performs the actual update operation.
 247                  * <p>
 248                  * The implementation of this class does nothing.
 249                  */
 250                 public void run() {
 251                         /* does nothing. */
 252                 }
 253
 254                 /**
 255                  * Waits for completion of this job or stopping of the WebOfTrust
 256                  * updater.
 257                  *
 258                  * @return {@code true} if this job finished successfully, {@code false}
 259                  *         otherwise
 260                  *
 261                  * @see WebOfTrustUpdater#stop()
 262                  */
 263                 @SuppressWarnings("synthetic-access")
 264                 public boolean waitForCompletion() {
 265                         synchronized (syncObject) {
 266                                 while (!finished && !shouldStop()) {
 267                                         try {
 268                                                 syncObject.wait();
 269                                         } catch (InterruptedException ie1) {
 270                                                 /* we’re looping, ignore. */
 271                                         }
 272                                 }
 273                                 return success;
 274                         }
 275                 }
 276
 277                 //
 278                 // PROTECTED METHODS
 279                 //
 280
 281                 /**
 282                  * Signals that this job has finished.
 283                  *
 284                  * @param success
 285                  *            {@code true} if this job finished successfully,
 286                  *            {@code false} otherwise
 287                  */
 288                 protected void finish(boolean success) {
 289                         synchronized (syncObject) {
 290                                 finished = true;
 291                                 this.success = success;
 292                                 syncObject.notifyAll();
 293                         }
 294                 }
 295
 296         }
 297
 298         /**
 299          * Base class for WebOfTrust trust update jobs.
 300          *
 301          * @author <a href="mailto:bombe@pterodactylus.net">David ‘Bombe’ Roden</a>
 302          */
 303         private class WebOfTrustTrustUpdateJob extends WebOfTrustUpdateJob {
 304
 305                 /** The identity giving the trust. */
 306                 protected final OwnIdentity truster;
 307
 308                 /** The identity receiving the trust. */
 309                 protected final Identity trustee;
 310
 311                 /**
 312                  * Creates a new trust update job.
 313                  *
 314                  * @param truster
 315                  *            The identity giving the trust
 316                  * @param trustee
 317                  *            The identity receiving the trust
 318                  */
 319                 @SuppressWarnings("synthetic-access")
 320                 public WebOfTrustTrustUpdateJob(OwnIdentity truster, Identity trustee) {
 321                         this.truster = truster;
 322                         this.trustee = trustee;
 323                 }
 324
 325                 //
 326                 // OBJECT METHODS
 327                 //
 328
 329                 /**
 330                  * {@inheritDoc}
 331                  */
 332                 @Override
 333                 public boolean equals(Object object) {
 334                         if ((object == null) || !object.getClass().equals(getClass())) {
 335                                 return false;
 336                         }
 337                         WebOfTrustTrustUpdateJob updateJob = (WebOfTrustTrustUpdateJob) object;
 338                         return ((truster == null) ? (updateJob.truster == null) : updateJob.truster.equals(truster)) && ((trustee == null) ? (updateJob.trustee == null) : updateJob.trustee.equals(trustee));
 339                 }
 340
 341                 /**
 342                  * {@inheritDoc}
 343                  */
 344                 @Override
 345                 public int hashCode() {
 346                         return getClass().hashCode() ^ ((truster == null) ? 0 : truster.hashCode()) ^ ((trustee == null) ? 0 : trustee.hashCode());
 347                 }
 348
 349                 /**
 350                  * {@inheritDoc}
 351                  */
 352                 @Override
 353                 public String toString() {
 354                         return String.format("%s[truster=%s,trustee=%s]", getClass().getSimpleName(), (truster == null) ? null : truster.getId(), (trustee == null) ? null : trustee.getId());
 355                 }
 356
 357         }
 358
 359         /**
 360          * Update job that sets the trust relation between two identities.
 361          *
 362          * @author <a href="mailto:bombe@pterodactylus.net">David ‘Bombe’ Roden</a>
 363          */
 364         private class SetTrustJob extends WebOfTrustTrustUpdateJob {
 365
 366                 /** The score of the relation. */
 367                 private final Integer score;
 368
 369                 /** The comment of the relation. */
 370                 private final String comment;
 371
 372                 /**
 373                  * Creates a new set trust job.
 374                  *
 375                  * @param truster
 376                  *            The identity giving the trust
 377                  * @param trustee
 378                  *            The identity receiving the trust
 379                  * @param score
 380                  *            The score of the trust (from -100 to 100, may be
 381                  *            {@code null} to remote the trust relation completely)
 382                  * @param comment
 383                  *            The comment of the trust relation
 384                  */
 385                 public SetTrustJob(OwnIdentity truster, Identity trustee, Integer score, String comment) {
 386                         super(truster, trustee);
 387                         this.score = score;
 388                         this.comment = comment;
 389                 }
 390
 391                 /**
 392                  * {@inheritDoc}
 393                  */
 394                 @Override
 395                 @SuppressWarnings("synthetic-access")
 396                 public void run() {
 397                         try {
 398                                 if (score != null) {
 399                                         if (trustee instanceof DefaultIdentity) {
 400                                                 ((DefaultIdentity) trustee).setTrust(truster, new Trust(score, null, 0));
 401                                         }
 402                                         webOfTrustConnector.setTrust(truster, trustee, score, comment);
 403                                 } else {
 404                                         if (trustee instanceof DefaultIdentity) {
 405                                                 ((DefaultIdentity) trustee).setTrust(truster, null);
 406                                         }
 407                                         webOfTrustConnector.removeTrust(truster, trustee);
 408                                 }
 409                                 finish(true);
 410                         } catch (WebOfTrustException wote1) {
 411                                 logger.log(Level.WARNING, "Could not set Trust value for " + truster + " -> " + trustee + " to " + score + " (" + comment + ")!", wote1);
 412                                 finish(false);
 413                         }
 414                 }
 415
 416         }
 417
 418         /**
 419          * Update job that retrieves the trust relation between two identities.
 420          *
 421          * @author <a href="mailto:bombe@pterodactylus.net">David ‘Bombe’ Roden</a>
 422          */
 423         private class GetTrustJob extends WebOfTrustTrustUpdateJob {
 424
 425                 /**
 426                  * Creates a new trust update job.
 427                  *
 428                  * @param truster
 429                  *            The identity giving the trust
 430                  * @param trustee
 431                  *            The identity receiving the trust
 432                  */
 433                 public GetTrustJob(OwnIdentity truster, Identity trustee) {
 434                         super(truster, trustee);
 435                 }
 436
 437                 /**
 438                  * {@inheritDoc}
 439                  */
 440                 @Override
 441                 @SuppressWarnings("synthetic-access")
 442                 public void run() {
 443                         try {
 444                                 Trust trust = webOfTrustConnector.getTrust(truster, trustee);
 445                                 if (trustee instanceof DefaultIdentity) {
 446                                         ((DefaultIdentity) trustee).setTrust(truster, trust);
 447                                 }
 448                                 finish(true);
 449                         } catch (PluginException pe1) {
 450                                 logger.log(Level.WARNING, "Could not get Trust value for " + truster + " -> " + trustee + "!", pe1);
 451                                 finish(false);
 452                         }
 453                 }
 454
 455         }
 456
 457         /**
 458          * Base class for context updates of an {@link OwnIdentity}.
 459          *
 460          * @author <a href="mailto:bombe@pterodactylus.net">David ‘Bombe’ Roden</a>
 461          */
 462         private class WebOfTrustContextUpdateJob extends WebOfTrustUpdateJob {
 463
 464                 /** The own identity whose contexts to manage. */
 465                 protected final OwnIdentity ownIdentity;
 466
 467                 /** The context to update. */
 468                 protected final String context;
 469
 470                 /**
 471                  * Creates a new context update job.
 472                  *
 473                  * @param ownIdentity
 474                  *            The own identity to update
 475                  * @param context
 476                  *            The context to update
 477                  */
 478                 @SuppressWarnings("synthetic-access")
 479                 public WebOfTrustContextUpdateJob(OwnIdentity ownIdentity, String context) {
 480                         Validation.begin().isNotNull("OwnIdentity", ownIdentity).isNotNull("Context", context).check();
 481                         this.ownIdentity = ownIdentity;
 482                         this.context = context;
 483                 }
 484
 485                 //
 486                 // OBJECT METHODS
 487                 //
 488
 489                 /**
 490                  * {@inheritDoc}
 491                  */
 492                 @Override
 493                 public boolean equals(Object object) {
 494                         if ((object == null) || !object.getClass().equals(getClass())) {
 495                                 return false;
 496                         }
 497                         WebOfTrustContextUpdateJob updateJob = (WebOfTrustContextUpdateJob) object;
 498                         return updateJob.ownIdentity.equals(ownIdentity) && updateJob.context.equals(context);
 499                 }
 500
 501                 /**
 502                  * {@inheritDoc}
 503                  */
 504                 @Override
 505                 public int hashCode() {
 506                         return getClass().hashCode() ^ ownIdentity.hashCode() ^ context.hashCode();
 507                 }
 508
 509                 /**
 510                  * {@inheritDoc}
 511                  */
 512                 @Override
 513                 public String toString() {
 514                         return String.format("%s[ownIdentity=%s,context=%s]", getClass().getSimpleName(), ownIdentity, context);
 515                 }
 516
 517         }
 518
 519         /**
 520          * Job that adds a context to an {@link OwnIdentity}.
 521          *
 522          * @author <a href="mailto:bombe@pterodactylus.net">David ‘Bombe’ Roden</a>
 523          */
 524         private class AddContextJob extends WebOfTrustContextUpdateJob {
 525
 526                 /**
 527                  * Creates a new add-context job.
 528                  *
 529                  * @param ownIdentity
 530                  *            The own identity whose contexts to manage
 531                  * @param context
 532                  *            The context to add
 533                  */
 534                 public AddContextJob(OwnIdentity ownIdentity, String context) {
 535                         super(ownIdentity, context);
 536                 }
 537
 538                 /**
 539                  * {@inheritDoc}
 540                  */
 541                 @Override
 542                 @SuppressWarnings("synthetic-access")
 543                 public void run() {
 544                         try {
 545                                 webOfTrustConnector.addContext(ownIdentity, context);
 546                                 ownIdentity.addContext(context);
 547                                 finish(true);
 548                         } catch (PluginException pe1) {
 549                                 logger.log(Level.WARNING, String.format("Could not add Context “%2$s” to Own Identity %1$s!", ownIdentity, context), pe1);
 550                                 finish(false);
 551                         }
 552                 }
 553
 554         }
 555
 556 }