src/main/java/net/pterodactylus/sone/freenet/wot/WebOfTrustConnector.java

   1 /*
   2  * Sone - WebOfTrustConnector.java - Copyright © 2010–2013 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.freenet.wot;
  19
  20 import java.util.HashMap;
  21 import java.util.HashSet;
  22 import java.util.Map;
  23 import java.util.Set;
  24 import java.util.concurrent.atomic.AtomicLong;
  25 import java.util.logging.Level;
  26 import java.util.logging.Logger;
  27
  28 import net.pterodactylus.sone.freenet.plugin.PluginConnector;
  29 import net.pterodactylus.sone.freenet.plugin.PluginException;
  30 import net.pterodactylus.sone.freenet.plugin.event.ReceivedReplyEvent;
  31 import net.pterodactylus.util.logging.Logging;
  32 import net.pterodactylus.util.number.Numbers;
  33
  34 import com.google.common.collect.MapMaker;
  35 import com.google.common.eventbus.Subscribe;
  36 import com.google.inject.Inject;
  37
  38 import freenet.support.SimpleFieldSet;
  39 import freenet.support.api.Bucket;
  40
  41 /**
  42  * Connector for the Web of Trust plugin.
  43  *
  44  * @author <a href="mailto:bombe@pterodactylus.net">David ‘Bombe’ Roden</a>
  45  */
  46 public class WebOfTrustConnector {
  47
  48         /** The logger. */
  49         private static final Logger logger = Logging.getLogger(WebOfTrustConnector.class);
  50
  51         /** The name of the WoT plugin. */
  52         private static final String WOT_PLUGIN_NAME = "plugins.WebOfTrust.WebOfTrust";
  53
  54         /** Counter for connection identifiers. */
  55         private final AtomicLong counter = new AtomicLong();
  56
  57         /** The plugin connector. */
  58         private final PluginConnector pluginConnector;
  59
  60         /** Map for replies. */
  61         private final Map<PluginIdentifier, Reply> replies = new MapMaker().makeMap();
  62
  63         /**
  64          * Creates a new Web of Trust connector that uses the given plugin
  65          * connector.
  66          *
  67          * @param pluginConnector
  68          *            The plugin connector
  69          */
  70         @Inject
  71         public WebOfTrustConnector(PluginConnector pluginConnector) {
  72                 this.pluginConnector = pluginConnector;
  73         }
  74
  75         //
  76         // ACTIONS
  77         //
  78
  79         /**
  80          * Stops the web of trust connector.
  81          */
  82         public void stop() {
  83                 /* does nothing. */
  84         }
  85
  86         /**
  87          * Loads all own identities from the Web of Trust plugin.
  88          *
  89          * @return All own identity
  90          * @throws WebOfTrustException
  91          *             if the own identities can not be loaded
  92          */
  93         public Set<OwnIdentity> loadAllOwnIdentities() throws WebOfTrustException {
  94                 Reply reply = performRequest(SimpleFieldSetConstructor.create().put("Message", "GetOwnIdentities").get());
  95                 SimpleFieldSet fields = reply.getFields();
  96                 int ownIdentityCounter = -1;
  97                 Set<OwnIdentity> ownIdentities = new HashSet<OwnIdentity>();
  98                 while (true) {
  99                         String id = fields.get("Identity" + ++ownIdentityCounter);
 100                         if (id == null) {
 101                                 break;
 102                         }
 103                         String requestUri = fields.get("RequestURI" + ownIdentityCounter);
 104                         String insertUri = fields.get("InsertURI" + ownIdentityCounter);
 105                         String nickname = fields.get("Nickname" + ownIdentityCounter);
 106                         DefaultOwnIdentity ownIdentity = new DefaultOwnIdentity(id, nickname, requestUri, insertUri);
 107                         ownIdentity.setContexts(parseContexts("Contexts" + ownIdentityCounter + ".", fields));
 108                         ownIdentity.setProperties(parseProperties("Properties" + ownIdentityCounter + ".", fields));
 109                         ownIdentities.add(ownIdentity);
 110                 }
 111                 return ownIdentities;
 112         }
 113
 114         /**
 115          * Loads all identities that the given identities trusts with a score of
 116          * more than 0.
 117          *
 118          * @param ownIdentity
 119          *            The own identity
 120          * @return All trusted identities
 121          * @throws PluginException
 122          *             if an error occured talking to the Web of Trust plugin
 123          */
 124         public Set<Identity> loadTrustedIdentities(OwnIdentity ownIdentity) throws PluginException {
 125                 return loadTrustedIdentities(ownIdentity, null);
 126         }
 127
 128         /**
 129          * Loads all identities that the given identities trusts with a score of
 130          * more than 0 and the (optional) given context.
 131          *
 132          * @param ownIdentity
 133          *            The own identity
 134          * @param context
 135          *            The context to filter, or {@code null}
 136          * @return All trusted identities
 137          * @throws PluginException
 138          *             if an error occured talking to the Web of Trust plugin
 139          */
 140         public Set<Identity> loadTrustedIdentities(OwnIdentity ownIdentity, String context) throws PluginException {
 141                 Reply reply = performRequest(SimpleFieldSetConstructor.create().put("Message", "GetIdentitiesByScore").put("Truster", ownIdentity.getId()).put("Selection", "+").put("Context", (context == null) ? "" : context).put("WantTrustValues", "true").get());
 142                 SimpleFieldSet fields = reply.getFields();
 143                 Set<Identity> identities = new HashSet<Identity>();
 144                 int identityCounter = -1;
 145                 while (true) {
 146                         String id = fields.get("Identity" + ++identityCounter);
 147                         if (id == null) {
 148                                 break;
 149                         }
 150                         String nickname = fields.get("Nickname" + identityCounter);
 151                         String requestUri = fields.get("RequestURI" + identityCounter);
 152                         DefaultIdentity identity = new DefaultIdentity(id, nickname, requestUri);
 153                         identity.setContexts(parseContexts("Contexts" + identityCounter + ".", fields));
 154                         identity.setProperties(parseProperties("Properties" + identityCounter + ".", fields));
 155                         Integer trust = Numbers.safeParseInteger(fields.get("Trust" + identityCounter), null);
 156                         int score = Numbers.safeParseInteger(fields.get("Score" + identityCounter), 0);
 157                         int rank = Numbers.safeParseInteger(fields.get("Rank" + identityCounter), 0);
 158                         identity.setTrust(ownIdentity, new Trust(trust, score, rank));
 159                         identities.add(identity);
 160                 }
 161                 return identities;
 162         }
 163
 164         /**
 165          * Adds the given context to the given identity.
 166          *
 167          * @param ownIdentity
 168          *            The identity to add the context to
 169          * @param context
 170          *            The context to add
 171          * @throws PluginException
 172          *             if an error occured talking to the Web of Trust plugin
 173          */
 174         public void addContext(OwnIdentity ownIdentity, String context) throws PluginException {
 175                 performRequest(SimpleFieldSetConstructor.create().put("Message", "AddContext").put("Identity", ownIdentity.getId()).put("Context", context).get());
 176         }
 177
 178         /**
 179          * Removes the given context from the given identity.
 180          *
 181          * @param ownIdentity
 182          *            The identity to remove the context from
 183          * @param context
 184          *            The context to remove
 185          * @throws PluginException
 186          *             if an error occured talking to the Web of Trust plugin
 187          */
 188         public void removeContext(OwnIdentity ownIdentity, String context) throws PluginException {
 189                 performRequest(SimpleFieldSetConstructor.create().put("Message", "RemoveContext").put("Identity", ownIdentity.getId()).put("Context", context).get());
 190         }
 191
 192         /**
 193          * Returns the value of the property with the given name.
 194          *
 195          * @param identity
 196          *            The identity whose properties to check
 197          * @param name
 198          *            The name of the property to return
 199          * @return The value of the property, or {@code null} if there is no value
 200          * @throws PluginException
 201          *             if an error occured talking to the Web of Trust plugin
 202          */
 203         public String getProperty(Identity identity, String name) throws PluginException {
 204                 Reply reply = performRequest(SimpleFieldSetConstructor.create().put("Message", "GetProperty").put("Identity", identity.getId()).put("Property", name).get());
 205                 return reply.getFields().get("Property");
 206         }
 207
 208         /**
 209          * Sets the property with the given name to the given value.
 210          *
 211          * @param ownIdentity
 212          *            The identity to set the property on
 213          * @param name
 214          *            The name of the property to set
 215          * @param value
 216          *            The value to set
 217          * @throws PluginException
 218          *             if an error occured talking to the Web of Trust plugin
 219          */
 220         public void setProperty(OwnIdentity ownIdentity, String name, String value) throws PluginException {
 221                 performRequest(SimpleFieldSetConstructor.create().put("Message", "SetProperty").put("Identity", ownIdentity.getId()).put("Property", name).put("Value", value).get());
 222         }
 223
 224         /**
 225          * Removes the property with the given name.
 226          *
 227          * @param ownIdentity
 228          *            The identity to remove the property from
 229          * @param name
 230          *            The name of the property to remove
 231          * @throws PluginException
 232          *             if an error occured talking to the Web of Trust plugin
 233          */
 234         public void removeProperty(OwnIdentity ownIdentity, String name) throws PluginException {
 235                 performRequest(SimpleFieldSetConstructor.create().put("Message", "RemoveProperty").put("Identity", ownIdentity.getId()).put("Property", name).get());
 236         }
 237
 238         /**
 239          * Returns the trust for the given identity assigned to it by the given own
 240          * identity.
 241          *
 242          * @param ownIdentity
 243          *            The own identity
 244          * @param identity
 245          *            The identity to get the trust for
 246          * @return The trust for the given identity
 247          * @throws PluginException
 248          *             if an error occured talking to the Web of Trust plugin
 249          */
 250         public Trust getTrust(OwnIdentity ownIdentity, Identity identity) throws PluginException {
 251                 Reply getTrustReply = performRequest(SimpleFieldSetConstructor.create().put("Message", "GetIdentity").put("Truster", ownIdentity.getId()).put("Identity", identity.getId()).get());
 252                 String trust = getTrustReply.getFields().get("Trust");
 253                 String score = getTrustReply.getFields().get("Score");
 254                 String rank = getTrustReply.getFields().get("Rank");
 255                 Integer explicit = null;
 256                 Integer implicit = null;
 257                 Integer distance = null;
 258                 try {
 259                         explicit = Integer.valueOf(trust);
 260                 } catch (NumberFormatException nfe1) {
 261                         /* ignore. */
 262                 }
 263                 try {
 264                         implicit = Integer.valueOf(score);
 265                         distance = Integer.valueOf(rank);
 266                 } catch (NumberFormatException nfe1) {
 267                         /* ignore. */
 268                 }
 269                 return new Trust(explicit, implicit, distance);
 270         }
 271
 272         /**
 273          * Sets the trust for the given identity.
 274          *
 275          * @param ownIdentity
 276          *            The trusting identity
 277          * @param identity
 278          *            The trusted identity
 279          * @param trust
 280          *            The amount of trust (-100 thru 100)
 281          * @param comment
 282          *            The comment or explanation of the trust value
 283          * @throws PluginException
 284          *             if an error occured talking to the Web of Trust plugin
 285          */
 286         public void setTrust(OwnIdentity ownIdentity, Identity identity, int trust, String comment) throws PluginException {
 287                 performRequest(SimpleFieldSetConstructor.create().put("Message", "SetTrust").put("Truster", ownIdentity.getId()).put("Trustee", identity.getId()).put("Value", String.valueOf(trust)).put("Comment", comment).get());
 288         }
 289
 290         /**
 291          * Removes any trust assignment of the given own identity for the given
 292          * identity.
 293          *
 294          * @param ownIdentity
 295          *            The own identity
 296          * @param identity
 297          *            The identity to remove all trust for
 298          * @throws WebOfTrustException
 299          *             if an error occurs
 300          */
 301         public void removeTrust(OwnIdentity ownIdentity, Identity identity) throws WebOfTrustException {
 302                 performRequest(SimpleFieldSetConstructor.create().put("Message", "RemoveTrust").put("Truster", ownIdentity.getId()).put("Trustee", identity.getId()).get());
 303         }
 304
 305         /**
 306          * Pings the Web of Trust plugin. If the plugin can not be reached, a
 307          * {@link PluginException} is thrown.
 308          *
 309          * @throws PluginException
 310          *             if the plugin is not loaded
 311          */
 312         public void ping() throws PluginException {
 313                 performRequest(SimpleFieldSetConstructor.create().put("Message", "Ping").get());
 314         }
 315
 316         //
 317         // PRIVATE ACTIONS
 318         //
 319
 320         /**
 321          * Parses the contexts from the given fields.
 322          *
 323          * @param prefix
 324          *            The prefix to use to access the contexts
 325          * @param fields
 326          *            The fields to parse the contexts from
 327          * @return The parsed contexts
 328          */
 329         private static Set<String> parseContexts(String prefix, SimpleFieldSet fields) {
 330                 Set<String> contexts = new HashSet<String>();
 331                 int contextCounter = -1;
 332                 while (true) {
 333                         String context = fields.get(prefix + "Context" + ++contextCounter);
 334                         if (context == null) {
 335                                 break;
 336                         }
 337                         contexts.add(context);
 338                 }
 339                 return contexts;
 340         }
 341
 342         /**
 343          * Parses the properties from the given fields.
 344          *
 345          * @param prefix
 346          *            The prefix to use to access the properties
 347          * @param fields
 348          *            The fields to parse the properties from
 349          * @return The parsed properties
 350          */
 351         private static Map<String, String> parseProperties(String prefix, SimpleFieldSet fields) {
 352                 Map<String, String> properties = new HashMap<String, String>();
 353                 int propertiesCounter = -1;
 354                 while (true) {
 355                         String propertyName = fields.get(prefix + "Property" + ++propertiesCounter + ".Name");
 356                         if (propertyName == null) {
 357                                 break;
 358                         }
 359                         String propertyValue = fields.get(prefix + "Property" + propertiesCounter + ".Value");
 360                         properties.put(propertyName, propertyValue);
 361                 }
 362                 return properties;
 363         }
 364
 365         /**
 366          * Sends a request containing the given fields and waits for the target
 367          * message.
 368          *
 369          * @param fields
 370          *            The fields of the message
 371          * @return The reply message
 372          * @throws PluginException
 373          *             if the request could not be sent
 374          */
 375         private Reply performRequest(SimpleFieldSet fields) throws PluginException {
 376                 return performRequest(fields, null);
 377         }
 378
 379         /**
 380          * Sends a request containing the given fields and waits for the target
 381          * message.
 382          *
 383          * @param fields
 384          *            The fields of the message
 385          * @param data
 386          *            The payload of the message
 387          * @return The reply message
 388          * @throws PluginException
 389          *             if the request could not be sent
 390          */
 391         private Reply performRequest(SimpleFieldSet fields, Bucket data) throws PluginException {
 392                 String identifier = "FCP-Command-" + System.currentTimeMillis() + "-" + counter.getAndIncrement();
 393                 Reply reply = new Reply();
 394                 PluginIdentifier pluginIdentifier = new PluginIdentifier(WOT_PLUGIN_NAME, identifier);
 395                 replies.put(pluginIdentifier, reply);
 396
 397                 logger.log(Level.FINE, String.format("Sending FCP Request: %s", fields.get("Message")));
 398                 synchronized (reply) {
 399                         try {
 400                                 pluginConnector.sendRequest(WOT_PLUGIN_NAME, identifier, fields, data);
 401                                 while (reply.getFields() == null) {
 402                                         try {
 403                                                 reply.wait();
 404                                         } catch (InterruptedException ie1) {
 405                                                 logger.log(Level.WARNING, String.format("Got interrupted while waiting for reply on %s.", fields.get("Message")), ie1);
 406                                         }
 407                                 }
 408                         } finally {
 409                                 replies.remove(pluginIdentifier);
 410                         }
 411                 }
 412                 logger.log(Level.FINEST, String.format("Received FCP Response for %s: %s", fields.get("Message"), (reply.getFields() != null) ? reply.getFields().get("Message") : null));
 413                 if ((reply.getFields() == null) || "Error".equals(reply.getFields().get("Message"))) {
 414                         throw new PluginException("Could not perform request for " + fields.get("Message"));
 415                 }
 416                 return reply;
 417         }
 418
 419         /**
 420          * Notifies the connector that a plugin reply was received.
 421          *
 422          * @param receivedReplyEvent
 423          *            The event
 424          */
 425         @Subscribe
 426         public void receivedReply(ReceivedReplyEvent receivedReplyEvent) {
 427                 PluginIdentifier pluginIdentifier = new PluginIdentifier(receivedReplyEvent.pluginName(), receivedReplyEvent.identifier());
 428                 Reply reply = replies.remove(pluginIdentifier);
 429                 if (reply == null) {
 430                         return;
 431                 }
 432                 logger.log(Level.FINEST, String.format("Received Reply from Plugin: %s", receivedReplyEvent.fieldSet().get("Message")));
 433                 synchronized (reply) {
 434                         reply.setFields(receivedReplyEvent.fieldSet());
 435                         reply.setData(receivedReplyEvent.data());
 436                         reply.notify();
 437                 }
 438         }
 439
 440         /**
 441          * Container for the data of the reply from a plugin.
 442          *
 443          * @author <a href="mailto:bombe@pterodactylus.net">David ‘Bombe’ Roden</a>
 444          */
 445         private static class Reply {
 446
 447                 /** The fields of the reply. */
 448                 private SimpleFieldSet fields;
 449
 450                 /** The payload of the reply. */
 451                 private Bucket data;
 452
 453                 /** Empty constructor. */
 454                 public Reply() {
 455                         /* do nothing. */
 456                 }
 457
 458                 /**
 459                  * Returns the fields of the reply.
 460                  *
 461                  * @return The fields of the reply
 462                  */
 463                 public SimpleFieldSet getFields() {
 464                         return fields;
 465                 }
 466
 467                 /**
 468                  * Sets the fields of the reply.
 469                  *
 470                  * @param fields
 471                  *            The fields of the reply
 472                  */
 473                 public void setFields(SimpleFieldSet fields) {
 474                         this.fields = fields;
 475                 }
 476
 477                 /**
 478                  * Returns the payload of the reply.
 479                  *
 480                  * @return The payload of the reply (may be {@code null})
 481                  */
 482                 @SuppressWarnings("unused")
 483                 public Bucket getData() {
 484                         return data;
 485                 }
 486
 487                 /**
 488                  * Sets the payload of the reply.
 489                  *
 490                  * @param data
 491                  *            The payload of the reply (may be {@code null})
 492                  */
 493                 public void setData(Bucket data) {
 494                         this.data = data;
 495                 }
 496
 497         }
 498
 499         /**
 500          * Helper method to create {@link SimpleFieldSet}s with terser code.
 501          *
 502          * @author <a href="mailto:bombe@pterodactylus.net">David ‘Bombe’ Roden</a>
 503          */
 504         private static class SimpleFieldSetConstructor {
 505
 506                 /** The field set being created. */
 507                 private SimpleFieldSet simpleFieldSet;
 508
 509                 /**
 510                  * Creates a new simple field set constructor.
 511                  *
 512                  * @param shortLived
 513                  *            {@code true} if the resulting simple field set should be
 514                  *            short-lived, {@code false} otherwise
 515                  */
 516                 private SimpleFieldSetConstructor(boolean shortLived) {
 517                         simpleFieldSet = new SimpleFieldSet(shortLived);
 518                 }
 519
 520                 //
 521                 // ACCESSORS
 522                 //
 523
 524                 /**
 525                  * Returns the created simple field set.
 526                  *
 527                  * @return The created simple field set
 528                  */
 529                 public SimpleFieldSet get() {
 530                         return simpleFieldSet;
 531                 }
 532
 533                 /**
 534                  * Sets the field with the given name to the given value.
 535                  *
 536                  * @param name
 537                  *            The name of the fleld
 538                  * @param value
 539                  *            The value of the field
 540                  * @return This constructor (for method chaining)
 541                  */
 542                 public SimpleFieldSetConstructor put(String name, String value) {
 543                         simpleFieldSet.putOverwrite(name, value);
 544                         return this;
 545                 }
 546
 547                 //
 548                 // ACTIONS
 549                 //
 550
 551                 /**
 552                  * Creates a new simple field set constructor.
 553                  *
 554                  * @return The created simple field set constructor
 555                  */
 556                 public static SimpleFieldSetConstructor create() {
 557                         return create(true);
 558                 }
 559
 560                 /**
 561                  * Creates a new simple field set constructor.
 562                  *
 563                  * @param shortLived
 564                  *            {@code true} if the resulting simple field set should be
 565                  *            short-lived, {@code false} otherwise
 566                  * @return The created simple field set constructor
 567                  */
 568                 public static SimpleFieldSetConstructor create(boolean shortLived) {
 569                         SimpleFieldSetConstructor simpleFieldSetConstructor = new SimpleFieldSetConstructor(shortLived);
 570                         return simpleFieldSetConstructor;
 571                 }
 572
 573         }
 574
 575         /**
 576          * Container for identifying plugins. Plugins are identified by their plugin
 577          * name and their unique identifier.
 578          *
 579          * @author <a href="mailto:d.roden@xplosion.de">David Roden</a>
 580          */
 581         private static class PluginIdentifier {
 582
 583                 /** The plugin name. */
 584                 private final String pluginName;
 585
 586                 /** The plugin identifier. */
 587                 private final String identifier;
 588
 589                 /**
 590                  * Creates a new plugin identifier.
 591                  *
 592                  * @param pluginName
 593                  *            The name of the plugin
 594                  * @param identifier
 595                  *            The identifier of the plugin
 596                  */
 597                 public PluginIdentifier(String pluginName, String identifier) {
 598                         this.pluginName = pluginName;
 599                         this.identifier = identifier;
 600                 }
 601
 602                 //
 603                 // OBJECT METHODS
 604                 //
 605
 606                 /**
 607                  * {@inheritDoc}
 608                  */
 609                 @Override
 610                 public int hashCode() {
 611                         return pluginName.hashCode() ^ identifier.hashCode();
 612                 }
 613
 614                 /**
 615                  * {@inheritDoc}
 616                  */
 617                 @Override
 618                 public boolean equals(Object object) {
 619                         if (!(object instanceof PluginIdentifier)) {
 620                                 return false;
 621                         }
 622                         PluginIdentifier pluginIdentifier = (PluginIdentifier) object;
 623                         return pluginName.equals(pluginIdentifier.pluginName) && identifier.equals(pluginIdentifier.identifier);
 624                 }
 625
 626         }
 627
 628 }