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

   1 /*
   2  * Sone - WebOfTrustConnector.java - Copyright © 2010–2012 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.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.ConnectorListener;
  29 import net.pterodactylus.sone.freenet.plugin.PluginConnector;
  30 import net.pterodactylus.sone.freenet.plugin.PluginException;
  31 import net.pterodactylus.util.logging.Logging;
  32 import net.pterodactylus.util.number.Numbers;
  33
  34 import com.google.inject.Inject;
  35
  36 import freenet.support.SimpleFieldSet;
  37 import freenet.support.api.Bucket;
  38
  39 /**
  40  * Connector for the Web of Trust plugin.
  41  *
  42  * @author <a href="mailto:bombe@pterodactylus.net">David ‘Bombe’ Roden</a>
  43  */
  44 public class WebOfTrustConnector {
  45
  46         /** The logger. */
  47         private static final Logger logger = Logging.getLogger(WebOfTrustConnector.class);
  48
  49         /** The name of the WoT plugin. */
  50         private static final String WOT_PLUGIN_NAME = "plugins.WebOfTrust.WebOfTrust";
  51
  52         /** Counter for connection identifiers. */
  53         private final AtomicLong counter = new AtomicLong();
  54
  55         /** The plugin connector. */
  56         private final PluginConnector pluginConnector;
  57
  58         /**
  59          * Creates a new Web of Trust connector that uses the given plugin
  60          * connector.
  61          *
  62          * @param pluginConnector
  63          *            The plugin connector
  64          */
  65         @Inject
  66         public WebOfTrustConnector(PluginConnector pluginConnector) {
  67                 this.pluginConnector = pluginConnector;
  68         }
  69
  70         //
  71         // ACTIONS
  72         //
  73
  74         /**
  75          * Stops the web of trust connector.
  76          */
  77         public void stop() {
  78                 /* does nothing. */
  79         }
  80
  81         /**
  82          * Loads all own identities from the Web of Trust plugin.
  83          *
  84          * @return All own identity
  85          * @throws WebOfTrustException
  86          *             if the own identities can not be loaded
  87          */
  88         public Set<OwnIdentity> loadAllOwnIdentities() throws WebOfTrustException {
  89                 Reply reply = performRequest(SimpleFieldSetConstructor.create().put("Message", "GetOwnIdentities").get());
  90                 SimpleFieldSet fields = reply.getFields();
  91                 int ownIdentityCounter = -1;
  92                 Set<OwnIdentity> ownIdentities = new HashSet<OwnIdentity>();
  93                 while (true) {
  94                         String id = fields.get("Identity" + ++ownIdentityCounter);
  95                         if (id == null) {
  96                                 break;
  97                         }
  98                         String requestUri = fields.get("RequestURI" + ownIdentityCounter);
  99                         String insertUri = fields.get("InsertURI" + ownIdentityCounter);
 100                         String nickname = fields.get("Nickname" + ownIdentityCounter);
 101                         DefaultOwnIdentity ownIdentity = new DefaultOwnIdentity(id, nickname, requestUri, insertUri);
 102                         ownIdentity.setContexts(parseContexts("Contexts" + ownIdentityCounter + ".", fields));
 103                         ownIdentity.setProperties(parseProperties("Properties" + ownIdentityCounter + ".", fields));
 104                         ownIdentities.add(ownIdentity);
 105                 }
 106                 return ownIdentities;
 107         }
 108
 109         /**
 110          * Loads all identities that the given identities trusts with a score of
 111          * more than 0.
 112          *
 113          * @param ownIdentity
 114          *            The own identity
 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) throws PluginException {
 120                 return loadTrustedIdentities(ownIdentity, null);
 121         }
 122
 123         /**
 124          * Loads all identities that the given identities trusts with a score of
 125          * more than 0 and the (optional) given context.
 126          *
 127          * @param ownIdentity
 128          *            The own identity
 129          * @param context
 130          *            The context to filter, or {@code null}
 131          * @return All trusted identities
 132          * @throws PluginException
 133          *             if an error occured talking to the Web of Trust plugin
 134          */
 135         public Set<Identity> loadTrustedIdentities(OwnIdentity ownIdentity, String context) throws PluginException {
 136                 Reply reply = performRequest(SimpleFieldSetConstructor.create().put("Message", "GetIdentitiesByScore").put("Truster", ownIdentity.getId()).put("Selection", "+").put("Context", (context == null) ? "" : context).put("WantTrustValues", "true").get());
 137                 SimpleFieldSet fields = reply.getFields();
 138                 Set<Identity> identities = new HashSet<Identity>();
 139                 int identityCounter = -1;
 140                 while (true) {
 141                         String id = fields.get("Identity" + ++identityCounter);
 142                         if (id == null) {
 143                                 break;
 144                         }
 145                         String nickname = fields.get("Nickname" + identityCounter);
 146                         String requestUri = fields.get("RequestURI" + identityCounter);
 147                         DefaultIdentity identity = new DefaultIdentity(id, nickname, requestUri);
 148                         identity.setContexts(parseContexts("Contexts" + identityCounter + ".", fields));
 149                         identity.setProperties(parseProperties("Properties" + identityCounter + ".", fields));
 150                         Integer trust = Numbers.safeParseInteger(fields.get("Trust" + identityCounter), null);
 151                         int score = Numbers.safeParseInteger(fields.get("Score" + identityCounter), 0);
 152                         int rank = Numbers.safeParseInteger(fields.get("Rank" + identityCounter), 0);
 153                         identity.setTrust(ownIdentity, new Trust(trust, score, rank));
 154                         identities.add(identity);
 155                 }
 156                 return identities;
 157         }
 158
 159         /**
 160          * Adds the given context to the given identity.
 161          *
 162          * @param ownIdentity
 163          *            The identity to add the context to
 164          * @param context
 165          *            The context to add
 166          * @throws PluginException
 167          *             if an error occured talking to the Web of Trust plugin
 168          */
 169         public void addContext(OwnIdentity ownIdentity, String context) throws PluginException {
 170                 performRequest(SimpleFieldSetConstructor.create().put("Message", "AddContext").put("Identity", ownIdentity.getId()).put("Context", context).get());
 171         }
 172
 173         /**
 174          * Removes the given context from the given identity.
 175          *
 176          * @param ownIdentity
 177          *            The identity to remove the context from
 178          * @param context
 179          *            The context to remove
 180          * @throws PluginException
 181          *             if an error occured talking to the Web of Trust plugin
 182          */
 183         public void removeContext(OwnIdentity ownIdentity, String context) throws PluginException {
 184                 performRequest(SimpleFieldSetConstructor.create().put("Message", "RemoveContext").put("Identity", ownIdentity.getId()).put("Context", context).get());
 185         }
 186
 187         /**
 188          * Returns the value of the property with the given name.
 189          *
 190          * @param identity
 191          *            The identity whose properties to check
 192          * @param name
 193          *            The name of the property to return
 194          * @return The value of the property, or {@code null} if there is no value
 195          * @throws PluginException
 196          *             if an error occured talking to the Web of Trust plugin
 197          */
 198         public String getProperty(Identity identity, String name) throws PluginException {
 199                 Reply reply = performRequest(SimpleFieldSetConstructor.create().put("Message", "GetProperty").put("Identity", identity.getId()).put("Property", name).get());
 200                 return reply.getFields().get("Property");
 201         }
 202
 203         /**
 204          * Sets the property with the given name to the given value.
 205          *
 206          * @param ownIdentity
 207          *            The identity to set the property on
 208          * @param name
 209          *            The name of the property to set
 210          * @param value
 211          *            The value to set
 212          * @throws PluginException
 213          *             if an error occured talking to the Web of Trust plugin
 214          */
 215         public void setProperty(OwnIdentity ownIdentity, String name, String value) throws PluginException {
 216                 performRequest(SimpleFieldSetConstructor.create().put("Message", "SetProperty").put("Identity", ownIdentity.getId()).put("Property", name).put("Value", value).get());
 217         }
 218
 219         /**
 220          * Removes the property with the given name.
 221          *
 222          * @param ownIdentity
 223          *            The identity to remove the property from
 224          * @param name
 225          *            The name of the property to remove
 226          * @throws PluginException
 227          *             if an error occured talking to the Web of Trust plugin
 228          */
 229         public void removeProperty(OwnIdentity ownIdentity, String name) throws PluginException {
 230                 performRequest(SimpleFieldSetConstructor.create().put("Message", "RemoveProperty").put("Identity", ownIdentity.getId()).put("Property", name).get());
 231         }
 232
 233         /**
 234          * Returns the trust for the given identity assigned to it by the given own
 235          * identity.
 236          *
 237          * @param ownIdentity
 238          *            The own identity
 239          * @param identity
 240          *            The identity to get the trust for
 241          * @return The trust for the given identity
 242          * @throws PluginException
 243          *             if an error occured talking to the Web of Trust plugin
 244          */
 245         public Trust getTrust(OwnIdentity ownIdentity, Identity identity) throws PluginException {
 246                 Reply getTrustReply = performRequest(SimpleFieldSetConstructor.create().put("Message", "GetIdentity").put("Truster", ownIdentity.getId()).put("Identity", identity.getId()).get());
 247                 String trust = getTrustReply.getFields().get("Trust");
 248                 String score = getTrustReply.getFields().get("Score");
 249                 String rank = getTrustReply.getFields().get("Rank");
 250                 Integer explicit = null;
 251                 Integer implicit = null;
 252                 Integer distance = null;
 253                 try {
 254                         explicit = Integer.valueOf(trust);
 255                 } catch (NumberFormatException nfe1) {
 256                         /* ignore. */
 257                 }
 258                 try {
 259                         implicit = Integer.valueOf(score);
 260                         distance = Integer.valueOf(rank);
 261                 } catch (NumberFormatException nfe1) {
 262                         /* ignore. */
 263                 }
 264                 return new Trust(explicit, implicit, distance);
 265         }
 266
 267         /**
 268          * Sets the trust for the given identity.
 269          *
 270          * @param ownIdentity
 271          *            The trusting identity
 272          * @param identity
 273          *            The trusted identity
 274          * @param trust
 275          *            The amount of trust (-100 thru 100)
 276          * @param comment
 277          *            The comment or explanation of the trust value
 278          * @throws PluginException
 279          *             if an error occured talking to the Web of Trust plugin
 280          */
 281         public void setTrust(OwnIdentity ownIdentity, Identity identity, int trust, String comment) throws PluginException {
 282                 performRequest(SimpleFieldSetConstructor.create().put("Message", "SetTrust").put("Truster", ownIdentity.getId()).put("Trustee", identity.getId()).put("Value", String.valueOf(trust)).put("Comment", comment).get());
 283         }
 284
 285         /**
 286          * Removes any trust assignment of the given own identity for the given
 287          * identity.
 288          *
 289          * @param ownIdentity
 290          *            The own identity
 291          * @param identity
 292          *            The identity to remove all trust for
 293          * @throws WebOfTrustException
 294          *             if an error occurs
 295          */
 296         public void removeTrust(OwnIdentity ownIdentity, Identity identity) throws WebOfTrustException {
 297                 performRequest(SimpleFieldSetConstructor.create().put("Message", "RemoveTrust").put("Truster", ownIdentity.getId()).put("Trustee", identity.getId()).get());
 298         }
 299
 300         /**
 301          * Pings the Web of Trust plugin. If the plugin can not be reached, a
 302          * {@link PluginException} is thrown.
 303          *
 304          * @throws PluginException
 305          *             if the plugin is not loaded
 306          */
 307         public void ping() throws PluginException {
 308                 performRequest(SimpleFieldSetConstructor.create().put("Message", "Ping").get());
 309         }
 310
 311         //
 312         // PRIVATE ACTIONS
 313         //
 314
 315         /**
 316          * Parses the contexts from the given fields.
 317          *
 318          * @param prefix
 319          *            The prefix to use to access the contexts
 320          * @param fields
 321          *            The fields to parse the contexts from
 322          * @return The parsed contexts
 323          */
 324         private static Set<String> parseContexts(String prefix, SimpleFieldSet fields) {
 325                 Set<String> contexts = new HashSet<String>();
 326                 int contextCounter = -1;
 327                 while (true) {
 328                         String context = fields.get(prefix + "Context" + ++contextCounter);
 329                         if (context == null) {
 330                                 break;
 331                         }
 332                         contexts.add(context);
 333                 }
 334                 return contexts;
 335         }
 336
 337         /**
 338          * Parses the properties from the given fields.
 339          *
 340          * @param prefix
 341          *            The prefix to use to access the properties
 342          * @param fields
 343          *            The fields to parse the properties from
 344          * @return The parsed properties
 345          */
 346         private static Map<String, String> parseProperties(String prefix, SimpleFieldSet fields) {
 347                 Map<String, String> properties = new HashMap<String, String>();
 348                 int propertiesCounter = -1;
 349                 while (true) {
 350                         String propertyName = fields.get(prefix + "Property" + ++propertiesCounter + ".Name");
 351                         if (propertyName == null) {
 352                                 break;
 353                         }
 354                         String propertyValue = fields.get(prefix + "Property" + propertiesCounter + ".Value");
 355                         properties.put(propertyName, propertyValue);
 356                 }
 357                 return properties;
 358         }
 359
 360         /**
 361          * Sends a request containing the given fields and waits for the target
 362          * message.
 363          *
 364          * @param fields
 365          *            The fields 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) throws PluginException {
 371                 return performRequest(fields, null);
 372         }
 373
 374         /**
 375          * Sends a request containing the given fields and waits for the target
 376          * message.
 377          *
 378          * @param fields
 379          *            The fields of the message
 380          * @param data
 381          *            The payload of the message
 382          * @return The reply message
 383          * @throws PluginException
 384          *             if the request could not be sent
 385          */
 386         private Reply performRequest(SimpleFieldSet fields, Bucket data) throws PluginException {
 387                 final String identifier = "FCP-Command-" + System.currentTimeMillis() + "-" + counter.getAndIncrement();
 388                 final Reply reply = new Reply();
 389                 logger.log(Level.FINE, String.format("Sending FCP Request: %s", fields.get("Message")));
 390                 ConnectorListener connectorListener = new ConnectorListener() {
 391
 392                         @Override
 393                         @SuppressWarnings("synthetic-access")
 394                         public void receivedReply(PluginConnector pluginConnector, SimpleFieldSet fields, Bucket data) {
 395                                 String messageName = fields.get("Message");
 396                                 logger.log(Level.FINEST, String.format("Received Reply from Plugin: %s", messageName));
 397                                 synchronized (reply) {
 398                                         reply.setFields(fields);
 399                                         reply.setData(data);
 400                                         reply.notify();
 401                                 }
 402                         }
 403                 };
 404                 pluginConnector.addConnectorListener(WOT_PLUGIN_NAME, identifier, connectorListener);
 405                 synchronized (reply) {
 406                         try {
 407                                 pluginConnector.sendRequest(WOT_PLUGIN_NAME, identifier, fields, data);
 408                                 while (reply.getFields() == null) {
 409                                         try {
 410                                                 reply.wait();
 411                                         } catch (InterruptedException ie1) {
 412                                                 logger.log(Level.WARNING, String.format("Got interrupted while waiting for reply on %s.", fields.get("Message")), ie1);
 413                                         }
 414                                 }
 415                         } finally {
 416                                 pluginConnector.removeConnectorListener(WOT_PLUGIN_NAME, identifier, connectorListener);
 417                         }
 418                 }
 419                 logger.log(Level.FINEST, String.format("Received FCP Response for %s: %s", fields.get("Message"), (reply.getFields() != null) ? reply.getFields().get("Message") : null));
 420                 if ((reply.getFields() == null) || "Error".equals(reply.getFields().get("Message"))) {
 421                         throw new PluginException("Could not perform request for " + fields.get("Message"));
 422                 }
 423                 return reply;
 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 }