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(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          * Sets the trust for the given identity.
 223          *
 224          * @param ownIdentity
 225          *            The trusting identity
 226          * @param identity
 227          *            The trusted identity
 228          * @param trust
 229          *            The amount of trust (-100 thru 100)
 230          * @param comment
 231          *            The comment or explanation of the trust value
 232          * @throws PluginException
 233          *             if an error occured talking to the Web of Trust plugin
 234          */
 235         public void setTrust(OwnIdentity ownIdentity, Identity identity, int trust, String comment) throws PluginException {
 236                 performRequest(SimpleFieldSetConstructor.create().put("Message", "SetTrust").put("Truster", ownIdentity.getId()).put("Trustee", identity.getId()).put("Value", String.valueOf(trust)).put("Comment", comment).get(), "TrustSet");
 237         }
 238
 239         /**
 240          * Pings the Web of Trust plugin. If the plugin can not be reached, a
 241          * {@link PluginException} is thrown.
 242          *
 243          * @throws PluginException
 244          *             if the plugin is not loaded
 245          */
 246         public void ping() throws PluginException {
 247                 performRequest(SimpleFieldSetConstructor.create().put("Message", "Ping").get(), "Pong");
 248         }
 249
 250         //
 251         // PRIVATE ACTIONS
 252         //
 253
 254         /**
 255          * Parses the contexts from the given fields.
 256          *
 257          * @param prefix
 258          *            The prefix to use to access the contexts
 259          * @param fields
 260          *            The fields to parse the contexts from
 261          * @return The parsed contexts
 262          */
 263         private Set<String> parseContexts(String prefix, SimpleFieldSet fields) {
 264                 Set<String> contexts = new HashSet<String>();
 265                 int contextCounter = -1;
 266                 while (true) {
 267                         String context = fields.get(prefix + "Context" + ++contextCounter);
 268                         if (context == null) {
 269                                 break;
 270                         }
 271                         contexts.add(context);
 272                 }
 273                 return contexts;
 274         }
 275
 276         /**
 277          * Parses the properties from the given fields.
 278          *
 279          * @param prefix
 280          *            The prefix to use to access the properties
 281          * @param fields
 282          *            The fields to parse the properties from
 283          * @return The parsed properties
 284          */
 285         private Map<String, String> parseProperties(String prefix, SimpleFieldSet fields) {
 286                 Map<String, String> properties = new HashMap<String, String>();
 287                 int propertiesCounter = -1;
 288                 while (true) {
 289                         String propertyName = fields.get(prefix + "Property" + ++propertiesCounter + ".Name");
 290                         if (propertyName == null) {
 291                                 break;
 292                         }
 293                         String propertyValue = fields.get(prefix + "Property" + propertiesCounter + ".Value");
 294                         properties.put(propertyName, propertyValue);
 295                 }
 296                 return properties;
 297         }
 298
 299         /**
 300          * Sends a request containing the given fields and waits for the target
 301          * message.
 302          *
 303          * @param fields
 304          *            The fields of the message
 305          * @param targetMessages
 306          *            The messages of the reply to wait for
 307          * @return The reply message
 308          * @throws PluginException
 309          *             if the request could not be sent
 310          */
 311         private Reply performRequest(SimpleFieldSet fields, String... targetMessages) throws PluginException {
 312                 return performRequest(fields, null, targetMessages);
 313         }
 314
 315         /**
 316          * Sends a request containing the given fields and waits for the target
 317          * message.
 318          *
 319          * @param fields
 320          *            The fields of the message
 321          * @param data
 322          *            The payload of the message
 323          * @param targetMessages
 324          *            The messages of the reply to wait for
 325          * @return The reply message
 326          * @throws PluginException
 327          *             if the request could not be sent
 328          */
 329         private Reply performRequest(SimpleFieldSet fields, Bucket data, String... targetMessages) throws PluginException {
 330                 @SuppressWarnings("synthetic-access")
 331                 Reply reply = new Reply();
 332                 for (String targetMessage : targetMessages) {
 333                         replies.put(targetMessage, reply);
 334                 }
 335                 replies.put("Error", reply);
 336                 synchronized (reply) {
 337                         pluginConnector.sendRequest(WOT_PLUGIN_NAME, PLUGIN_CONNECTION_IDENTIFIER, fields, data);
 338                         try {
 339                                 long now = System.currentTimeMillis();
 340                                 while ((reply.getFields() == null) && ((System.currentTimeMillis() - now) < 60000)) {
 341                                         reply.wait(60000 - (System.currentTimeMillis() - now));
 342                                 }
 343                                 if (reply.getFields() == null) {
 344                                         for (String targetMessage : targetMessages) {
 345                                                 replies.remove(targetMessage);
 346                                         }
 347                                         replies.remove("Error");
 348                                         throw new PluginException("Timeout waiting for " + targetMessages[0] + "!");
 349                                 }
 350                         } catch (InterruptedException ie1) {
 351                                 logger.log(Level.WARNING, "Got interrupted while waiting for reply on " + targetMessages[0] + ".", ie1);
 352                         }
 353                 }
 354                 for (String targetMessage : targetMessages) {
 355                         replies.remove(targetMessage);
 356                 }
 357                 replies.remove("Error");
 358                 if ((reply.getFields() != null) && reply.getFields().get("Message").equals("Error")) {
 359                         throw new PluginException("Could not perform request for " + targetMessages[0]);
 360                 }
 361                 return reply;
 362         }
 363
 364         //
 365         // INTERFACE ConnectorListener
 366         //
 367
 368         /**
 369          * {@inheritDoc}
 370          */
 371         @Override
 372         public void receivedReply(PluginConnector pluginConnector, SimpleFieldSet fields, Bucket data) {
 373                 String messageName = fields.get("Message");
 374                 logger.log(Level.FINEST, "Received Reply from Plugin: " + messageName);
 375                 Reply reply = replies.remove(messageName);
 376                 if (reply == null) {
 377                         logger.log(Level.FINE, "Not waiting for a “%s” message.", messageName);
 378                         return;
 379                 }
 380                 synchronized (reply) {
 381                         reply.setFields(fields);
 382                         reply.setData(data);
 383                         reply.notify();
 384                 }
 385         }
 386
 387         /**
 388          * Container for the data of the reply from a plugin.
 389          *
 390          * @author <a href="mailto:bombe@pterodactylus.net">David ‘Bombe’ Roden</a>
 391          */
 392         private static class Reply {
 393
 394                 /** The fields of the reply. */
 395                 private SimpleFieldSet fields;
 396
 397                 /** The payload of the reply. */
 398                 private Bucket data;
 399
 400                 /**
 401                  * Returns the fields of the reply.
 402                  *
 403                  * @return The fields of the reply
 404                  */
 405                 public SimpleFieldSet getFields() {
 406                         return fields;
 407                 }
 408
 409                 /**
 410                  * Sets the fields of the reply.
 411                  *
 412                  * @param fields
 413                  *            The fields of the reply
 414                  */
 415                 public void setFields(SimpleFieldSet fields) {
 416                         this.fields = fields;
 417                 }
 418
 419                 /**
 420                  * Returns the payload of the reply.
 421                  *
 422                  * @return The payload of the reply (may be {@code null})
 423                  */
 424                 @SuppressWarnings("unused")
 425                 public Bucket getData() {
 426                         return data;
 427                 }
 428
 429                 /**
 430                  * Sets the payload of the reply.
 431                  *
 432                  * @param data
 433                  *            The payload of the reply (may be {@code null})
 434                  */
 435                 public void setData(Bucket data) {
 436                         this.data = data;
 437                 }
 438
 439         }
 440
 441         /**
 442          * Helper method to create {@link SimpleFieldSet}s with terser code.
 443          *
 444          * @author <a href="mailto:bombe@pterodactylus.net">David ‘Bombe’ Roden</a>
 445          */
 446         private static class SimpleFieldSetConstructor {
 447
 448                 /** The field set being created. */
 449                 private SimpleFieldSet simpleFieldSet;
 450
 451                 /**
 452                  * Creates a new simple field set constructor.
 453                  *
 454                  * @param shortLived
 455                  *            {@code true} if the resulting simple field set should be
 456                  *            short-lived, {@code false} otherwise
 457                  */
 458                 private SimpleFieldSetConstructor(boolean shortLived) {
 459                         simpleFieldSet = new SimpleFieldSet(shortLived);
 460                 }
 461
 462                 //
 463                 // ACCESSORS
 464                 //
 465
 466                 /**
 467                  * Returns the created simple field set.
 468                  *
 469                  * @return The created simple field set
 470                  */
 471                 public SimpleFieldSet get() {
 472                         return simpleFieldSet;
 473                 }
 474
 475                 /**
 476                  * Sets the field with the given name to the given value.
 477                  *
 478                  * @param name
 479                  *            The name of the fleld
 480                  * @param value
 481                  *            The value of the field
 482                  * @return This constructor (for method chaining)
 483                  */
 484                 public SimpleFieldSetConstructor put(String name, String value) {
 485                         simpleFieldSet.putOverwrite(name, value);
 486                         return this;
 487                 }
 488
 489                 //
 490                 // ACTIONS
 491                 //
 492
 493                 /**
 494                  * Creates a new simple field set constructor.
 495                  *
 496                  * @return The created simple field set constructor
 497                  */
 498                 public static SimpleFieldSetConstructor create() {
 499                         return create(true);
 500                 }
 501
 502                 /**
 503                  * Creates a new simple field set constructor.
 504                  *
 505                  * @param shortLived
 506                  *            {@code true} if the resulting simple field set should be
 507                  *            short-lived, {@code false} otherwise
 508                  * @return The created simple field set constructor
 509                  */
 510                 public static SimpleFieldSetConstructor create(boolean shortLived) {
 511                         SimpleFieldSetConstructor simpleFieldSetConstructor = new SimpleFieldSetConstructor(shortLived);
 512                         return simpleFieldSetConstructor;
 513                 }
 514
 515         }
 516
 517 }