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