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

   1 /*
   2  * Sone - WebOfTrustConnector.java - Copyright © 2010 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.Collections;
  21 import java.util.HashMap;
  22 import java.util.HashSet;
  23 import java.util.Map;
  24 import java.util.Set;
  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 freenet.support.SimpleFieldSet;
  33 import freenet.support.api.Bucket;
  34
  35 /**
  36  * Connector for the Web of Trust plugin.
  37  *
  38  * @author <a href="mailto:bombe@pterodactylus.net">David ‘Bombe’ Roden</a>
  39  */
  40 public class WebOfTrustConnector implements ConnectorListener {
  41
  42         /** The logger. */
  43         private static final Logger logger = Logging.getLogger(WebOfTrustConnector.class);
  44
  45         /** The name of the WoT plugin. */
  46         private static final String WOT_PLUGIN_NAME = "plugins.WoT.WoT";
  47
  48         /** A random connection identifier. */
  49         private static final String PLUGIN_CONNECTION_IDENTIFIER = "Sone-WoT-Connector-" + Math.abs(Math.random());
  50
  51         /** The current replies that we wait for. */
  52         private final Map<String, Reply> replies = Collections.synchronizedMap(new HashMap<String, Reply>());
  53
  54         /** The plugin connector. */
  55         private final PluginConnector pluginConnector;
  56
  57         /**
  58          * Creates a new Web of Trust connector that uses the given plugin
  59          * connector.
  60          *
  61          * @param pluginConnector
  62          *            The plugin connector
  63          */
  64         public WebOfTrustConnector(PluginConnector pluginConnector) {
  65                 this.pluginConnector = pluginConnector;
  66                 pluginConnector.addConnectorListener(WOT_PLUGIN_NAME, PLUGIN_CONNECTION_IDENTIFIER, this);
  67         }
  68
  69         //
  70         // ACTIONS
  71         //
  72
  73         /**
  74          * Loads all own identities from the Web of Trust plugin.
  75          *
  76          * @return All own identity
  77          * @throws WebOfTrustException
  78          *             if the own identities can not be loaded
  79          */
  80         public Set<OwnIdentity> loadAllOwnIdentities() throws WebOfTrustException {
  81                 Reply reply = performRequest(SimpleFieldSetConstructor.create().put("Message", "GetOwnIdentities").get(), "OwnIdentities");
  82                 SimpleFieldSet fields = reply.getFields();
  83                 int ownIdentityCounter = -1;
  84                 Set<OwnIdentity> ownIdentities = new HashSet<OwnIdentity>();
  85                 while (true) {
  86                         String id = fields.get("Identity" + ++ownIdentityCounter);
  87                         if (id == null) {
  88                                 break;
  89                         }
  90                         String requestUri = fields.get("RequestURI" + ownIdentityCounter);
  91                         String insertUri = fields.get("InsertURI" + ownIdentityCounter);
  92                         String nickname = fields.get("Nickname" + ownIdentityCounter);
  93                         DefaultOwnIdentity ownIdentity = new DefaultOwnIdentity(this, id, nickname, requestUri, insertUri);
  94                         ownIdentity.setContextsPrivate(parseContexts("Contexts" + ownIdentityCounter + ".", fields));
  95                         ownIdentity.setPropertiesPrivate(parseProperties("Properties" + ownIdentityCounter + ".", fields));
  96                         ownIdentities.add(ownIdentity);
  97                 }
  98                 return ownIdentities;
  99         }
 100
 101         /**
 102          * Loads all identities that the given identities trusts with a score of
 103          * more than 0.
 104          *
 105          * @param ownIdentity
 106          *            The own identity
 107          * @return All trusted identities
 108          * @throws PluginException
 109          *             if an error occured talking to the Web of Trust plugin
 110          */
 111         public Set<Identity> loadTrustedIdentities(OwnIdentity ownIdentity) throws PluginException {
 112                 return loadTrustedIdentities(ownIdentity, null);
 113         }
 114
 115         /**
 116          * Loads all identities that the given identities trusts with a score of
 117          * more than 0 and the (optional) given context.
 118          *
 119          * @param ownIdentity
 120          *            The own identity
 121          * @param context
 122          *            The context to filter, or {@code null}
 123          * @return All trusted identities
 124          * @throws PluginException
 125          *             if an error occured talking to the Web of Trust plugin
 126          */
 127         public Set<Identity> loadTrustedIdentities(OwnIdentity ownIdentity, String context) throws PluginException {
 128                 Reply reply = performRequest(SimpleFieldSetConstructor.create().put("Message", "GetIdentitiesByScore").put("TreeOwner", ownIdentity.getId()).put("Selection", "+").put("Context", (context == null) ? "" : context).get(), "Identities");
 129                 SimpleFieldSet fields = reply.getFields();
 130                 Set<Identity> identities = new HashSet<Identity>();
 131                 int identityCounter = -1;
 132                 while (true) {
 133                         String id = fields.get("Identity" + ++identityCounter);
 134                         if (id == null) {
 135                                 break;
 136                         }
 137                         String nickname = fields.get("Nickname" + identityCounter);
 138                         String requestUri = fields.get("RequestURI" + identityCounter);
 139                         DefaultIdentity identity = new DefaultIdentity(this, id, nickname, requestUri);
 140                         identity.setContextsPrivate(parseContexts("Contexts" + identityCounter + ".", fields));
 141                         identity.setPropertiesPrivate(parseProperties("Properties" + identityCounter + ".", fields));
 142                         identities.add(identity);
 143                 }
 144                 return identities;
 145         }
 146
 147         /**
 148          * Adds the given context to the given identity.
 149          *
 150          * @param ownIdentity
 151          *            The identity to add the context to
 152          * @param context
 153          *            The context to add
 154          * @throws PluginException
 155          *             if an error occured talking to the Web of Trust plugin
 156          */
 157         public void addContext(OwnIdentity ownIdentity, String context) throws PluginException {
 158                 performRequest(SimpleFieldSetConstructor.create().put("Message", "AddContext").put("Identity", ownIdentity.getId()).put("Context", context).get(), "ContextAdded");
 159         }
 160
 161         /**
 162          * Removes the given context from the given identity.
 163          *
 164          * @param ownIdentity
 165          *            The identity to remove the context from
 166          * @param context
 167          *            The context to remove
 168          * @throws PluginException
 169          *             if an error occured talking to the Web of Trust plugin
 170          */
 171         public void removeContext(OwnIdentity ownIdentity, String context) throws PluginException {
 172                 performRequest(SimpleFieldSetConstructor.create().put("Message", "RemoveContext").put("Identity", ownIdentity.getId()).put("Context", context).get(), "ContextRemoved");
 173         }
 174
 175         /**
 176          * Returns the value of the property with the given name.
 177          *
 178          * @param identity
 179          *            The identity whose properties to check
 180          * @param name
 181          *            The name of the property to return
 182          * @return The value of the property, or {@code null} if there is no value
 183          * @throws PluginException
 184          *             if an error occured talking to the Web of Trust plugin
 185          */
 186         public String getProperty(Identity identity, String name) throws PluginException {
 187                 Reply reply = performRequest(SimpleFieldSetConstructor.create().put("Message", "GetProperty").put("Identity", identity.getId()).put("Property", name).get(), "PropertyValue");
 188                 return reply.getFields().get("Property");
 189         }
 190
 191         /**
 192          * Sets the property with the given name to the given value.
 193          *
 194          * @param ownIdentity
 195          *            The identity to set the property on
 196          * @param name
 197          *            The name of the property to set
 198          * @param value
 199          *            The value to set
 200          * @throws PluginException
 201          *             if an error occured talking to the Web of Trust plugin
 202          */
 203         public void setProperty(OwnIdentity ownIdentity, String name, String value) throws PluginException {
 204                 performRequest(SimpleFieldSetConstructor.create().put("Message", "SetProperty").put("Identity", ownIdentity.getId()).put("Property", name).put("Value", value).get(), "PropertyAdded");
 205         }
 206
 207         /**
 208          * Removes the property with the given name.
 209          *
 210          * @param ownIdentity
 211          *            The identity to remove the property from
 212          * @param name
 213          *            The name of the property to remove
 214          * @throws PluginException
 215          *             if an error occured talking to the Web of Trust plugin
 216          */
 217         public void removeProperty(OwnIdentity ownIdentity, String name) throws PluginException {
 218                 performRequest(SimpleFieldSetConstructor.create().put("Message", "RemoveProperty").put("Identity", ownIdentity.getId()).put("Property", name).get(), "PropertyRemoved");
 219         }
 220
 221         /**
 222          * Returns the trust for the given identity assigned to it by the given own
 223          * identity.
 224          *
 225          * @param ownIdentity
 226          *            The own identity
 227          * @param identity
 228          *            The identity to get the trust for
 229          * @return The trust for the given identity
 230          * @throws PluginException
 231          *             if an error occured talking to the Web of Trust plugin
 232          */
 233         public Trust getTrust(OwnIdentity ownIdentity, Identity identity) throws PluginException {
 234                 Reply getTrustReply = performRequest(SimpleFieldSetConstructor.create().put("Message", "GetIdentity").put("TreeOwner", ownIdentity.getId()).put("Identity", identity.getId()).get(), "Identity");
 235                 String trust = getTrustReply.getFields().get("Trust");
 236                 String score = getTrustReply.getFields().get("Score");
 237                 String rank = getTrustReply.getFields().get("Rank");
 238                 Integer explicit = null;
 239                 Integer implicit = null;
 240                 Integer distance = null;
 241                 try {
 242                         explicit = Integer.valueOf(trust);
 243                 } catch (NumberFormatException nfe1) {
 244                         /* ignore. */
 245                 }
 246                 try {
 247                         implicit = Integer.valueOf(score);
 248                         distance = Integer.valueOf(rank);
 249                 } catch (NumberFormatException nfe1) {
 250                         /* ignore. */
 251                 }
 252                 return new Trust(explicit, implicit, distance);
 253         }
 254
 255         /**
 256          * Sets the trust for the given identity.
 257          *
 258          * @param ownIdentity
 259          *            The trusting identity
 260          * @param identity
 261          *            The trusted identity
 262          * @param trust
 263          *            The amount of trust (-100 thru 100)
 264          * @param comment
 265          *            The comment or explanation of the trust value
 266          * @throws PluginException
 267          *             if an error occured talking to the Web of Trust plugin
 268          */
 269         public void setTrust(OwnIdentity ownIdentity, Identity identity, int trust, String comment) throws PluginException {
 270                 performRequest(SimpleFieldSetConstructor.create().put("Message", "SetTrust").put("Truster", ownIdentity.getId()).put("Trustee", identity.getId()).put("Value", String.valueOf(trust)).put("Comment", comment).get(), "TrustSet");
 271         }
 272
 273         /**
 274          * Pings the Web of Trust plugin. If the plugin can not be reached, a
 275          * {@link PluginException} is thrown.
 276          *
 277          * @throws PluginException
 278          *             if the plugin is not loaded
 279          */
 280         public void ping() throws PluginException {
 281                 performRequest(SimpleFieldSetConstructor.create().put("Message", "Ping").get(), "Pong");
 282         }
 283
 284         //
 285         // PRIVATE ACTIONS
 286         //
 287
 288         /**
 289          * Parses the contexts from the given fields.
 290          *
 291          * @param prefix
 292          *            The prefix to use to access the contexts
 293          * @param fields
 294          *            The fields to parse the contexts from
 295          * @return The parsed contexts
 296          */
 297         private Set<String> parseContexts(String prefix, SimpleFieldSet fields) {
 298                 Set<String> contexts = new HashSet<String>();
 299                 int contextCounter = -1;
 300                 while (true) {
 301                         String context = fields.get(prefix + "Context" + ++contextCounter);
 302                         if (context == null) {
 303                                 break;
 304                         }
 305                         contexts.add(context);
 306                 }
 307                 return contexts;
 308         }
 309
 310         /**
 311          * Parses the properties from the given fields.
 312          *
 313          * @param prefix
 314          *            The prefix to use to access the properties
 315          * @param fields
 316          *            The fields to parse the properties from
 317          * @return The parsed properties
 318          */
 319         private Map<String, String> parseProperties(String prefix, SimpleFieldSet fields) {
 320                 Map<String, String> properties = new HashMap<String, String>();
 321                 int propertiesCounter = -1;
 322                 while (true) {
 323                         String propertyName = fields.get(prefix + "Property" + ++propertiesCounter + ".Name");
 324                         if (propertyName == null) {
 325                                 break;
 326                         }
 327                         String propertyValue = fields.get(prefix + "Property" + propertiesCounter + ".Value");
 328                         properties.put(propertyName, propertyValue);
 329                 }
 330                 return properties;
 331         }
 332
 333         /**
 334          * Sends a request containing the given fields and waits for the target
 335          * message.
 336          *
 337          * @param fields
 338          *            The fields of the message
 339          * @param targetMessages
 340          *            The messages of the reply to wait for
 341          * @return The reply message
 342          * @throws PluginException
 343          *             if the request could not be sent
 344          */
 345         private Reply performRequest(SimpleFieldSet fields, String... targetMessages) throws PluginException {
 346                 return performRequest(fields, null, targetMessages);
 347         }
 348
 349         /**
 350          * Sends a request containing the given fields and waits for the target
 351          * message.
 352          *
 353          * @param fields
 354          *            The fields of the message
 355          * @param data
 356          *            The payload of the message
 357          * @param targetMessages
 358          *            The messages of the reply to wait for
 359          * @return The reply message
 360          * @throws PluginException
 361          *             if the request could not be sent
 362          */
 363         private Reply performRequest(SimpleFieldSet fields, Bucket data, String... targetMessages) throws PluginException {
 364                 @SuppressWarnings("synthetic-access")
 365                 Reply reply = new Reply();
 366                 for (String targetMessage : targetMessages) {
 367                         replies.put(targetMessage, reply);
 368                 }
 369                 replies.put("Error", reply);
 370                 synchronized (reply) {
 371                         pluginConnector.sendRequest(WOT_PLUGIN_NAME, PLUGIN_CONNECTION_IDENTIFIER, fields, data);
 372                         try {
 373                                 long now = System.currentTimeMillis();
 374                                 while ((reply.getFields() == null) && ((System.currentTimeMillis() - now) < 60000)) {
 375                                         reply.wait(60000 - (System.currentTimeMillis() - now));
 376                                 }
 377                                 if (reply.getFields() == null) {
 378                                         for (String targetMessage : targetMessages) {
 379                                                 replies.remove(targetMessage);
 380                                         }
 381                                         replies.remove("Error");
 382                                         throw new PluginException("Timeout waiting for " + targetMessages[0] + "!");
 383                                 }
 384                         } catch (InterruptedException ie1) {
 385                                 logger.log(Level.WARNING, "Got interrupted while waiting for reply on " + targetMessages[0] + ".", ie1);
 386                         }
 387                 }
 388                 for (String targetMessage : targetMessages) {
 389                         replies.remove(targetMessage);
 390                 }
 391                 replies.remove("Error");
 392                 if ((reply.getFields() != null) && reply.getFields().get("Message").equals("Error")) {
 393                         throw new PluginException("Could not perform request for " + targetMessages[0]);
 394                 }
 395                 return reply;
 396         }
 397
 398         //
 399         // INTERFACE ConnectorListener
 400         //
 401
 402         /**
 403          * {@inheritDoc}
 404          */
 405         @Override
 406         public void receivedReply(PluginConnector pluginConnector, SimpleFieldSet fields, Bucket data) {
 407                 String messageName = fields.get("Message");
 408                 logger.log(Level.FINEST, "Received Reply from Plugin: " + messageName);
 409                 Reply reply = replies.remove(messageName);
 410                 if (reply == null) {
 411                         logger.log(Level.FINE, "Not waiting for a “%s” message.", messageName);
 412                         return;
 413                 }
 414                 synchronized (reply) {
 415                         reply.setFields(fields);
 416                         reply.setData(data);
 417                         reply.notify();
 418                 }
 419         }
 420
 421         /**
 422          * Container for the data of the reply from a plugin.
 423          *
 424          * @author <a href="mailto:bombe@pterodactylus.net">David ‘Bombe’ Roden</a>
 425          */
 426         private static class Reply {
 427
 428                 /** The fields of the reply. */
 429                 private SimpleFieldSet fields;
 430
 431                 /** The payload of the reply. */
 432                 private Bucket data;
 433
 434                 /**
 435                  * Returns the fields of the reply.
 436                  *
 437                  * @return The fields of the reply
 438                  */
 439                 public SimpleFieldSet getFields() {
 440                         return fields;
 441                 }
 442
 443                 /**
 444                  * Sets the fields of the reply.
 445                  *
 446                  * @param fields
 447                  *            The fields of the reply
 448                  */
 449                 public void setFields(SimpleFieldSet fields) {
 450                         this.fields = fields;
 451                 }
 452
 453                 /**
 454                  * Returns the payload of the reply.
 455                  *
 456                  * @return The payload of the reply (may be {@code null})
 457                  */
 458                 @SuppressWarnings("unused")
 459                 public Bucket getData() {
 460                         return data;
 461                 }
 462
 463                 /**
 464                  * Sets the payload of the reply.
 465                  *
 466                  * @param data
 467                  *            The payload of the reply (may be {@code null})
 468                  */
 469                 public void setData(Bucket data) {
 470                         this.data = data;
 471                 }
 472
 473         }
 474
 475         /**
 476          * Helper method to create {@link SimpleFieldSet}s with terser code.
 477          *
 478          * @author <a href="mailto:bombe@pterodactylus.net">David ‘Bombe’ Roden</a>
 479          */
 480         private static class SimpleFieldSetConstructor {
 481
 482                 /** The field set being created. */
 483                 private SimpleFieldSet simpleFieldSet;
 484
 485                 /**
 486                  * Creates a new simple field set constructor.
 487                  *
 488                  * @param shortLived
 489                  *            {@code true} if the resulting simple field set should be
 490                  *            short-lived, {@code false} otherwise
 491                  */
 492                 private SimpleFieldSetConstructor(boolean shortLived) {
 493                         simpleFieldSet = new SimpleFieldSet(shortLived);
 494                 }
 495
 496                 //
 497                 // ACCESSORS
 498                 //
 499
 500                 /**
 501                  * Returns the created simple field set.
 502                  *
 503                  * @return The created simple field set
 504                  */
 505                 public SimpleFieldSet get() {
 506                         return simpleFieldSet;
 507                 }
 508
 509                 /**
 510                  * Sets the field with the given name to the given value.
 511                  *
 512                  * @param name
 513                  *            The name of the fleld
 514                  * @param value
 515                  *            The value of the field
 516                  * @return This constructor (for method chaining)
 517                  */
 518                 public SimpleFieldSetConstructor put(String name, String value) {
 519                         simpleFieldSet.putOverwrite(name, value);
 520                         return this;
 521                 }
 522
 523                 //
 524                 // ACTIONS
 525                 //
 526
 527                 /**
 528                  * Creates a new simple field set constructor.
 529                  *
 530                  * @return The created simple field set constructor
 531                  */
 532                 public static SimpleFieldSetConstructor create() {
 533                         return create(true);
 534                 }
 535
 536                 /**
 537                  * Creates a new simple field set constructor.
 538                  *
 539                  * @param shortLived
 540                  *            {@code true} if the resulting simple field set should be
 541                  *            short-lived, {@code false} otherwise
 542                  * @return The created simple field set constructor
 543                  */
 544                 public static SimpleFieldSetConstructor create(boolean shortLived) {
 545                         SimpleFieldSetConstructor simpleFieldSetConstructor = new SimpleFieldSetConstructor(shortLived);
 546                         return simpleFieldSetConstructor;
 547                 }
 548
 549         }
 550
 551 }