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