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