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