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.util.logging.Logging;
  29 import freenet.support.SimpleFieldSet;
  30 import freenet.support.api.Bucket;
  31
  32 /**
  33  * Connector for the Web of Trust plugin.
  34  *
  35  * @author <a href="mailto:bombe@pterodactylus.net">David ‘Bombe’ Roden</a>
  36  */
  37 public class WebOfTrustConnector implements ConnectorListener {
  38
  39         /** The logger. */
  40         private static final Logger logger = Logging.getLogger(WebOfTrustConnector.class);
  41
  42         /** The name of the WoT plugin. */
  43         private static final String WOT_PLUGIN_NAME = "plugins.WoT.WoT";
  44
  45         /** A random connection identifier. */
  46         private static final String PLUGIN_CONNECTION_IDENTIFIER = "Sone-WoT-Connector-" + Math.abs(Math.random());
  47
  48         /** The current replies that we wait for. */
  49         private final Map<String, Reply> replies = Collections.synchronizedMap(new HashMap<String, Reply>());
  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                 pluginConnector.addConnectorListener(WOT_PLUGIN_NAME, PLUGIN_CONNECTION_IDENTIFIER, this);
  64         }
  65
  66         //
  67         // ACTIONS
  68         //
  69
  70         /**
  71          * Loads all own identities from the Web of Trust plugin.
  72          *
  73          * @return All own identity
  74          * @throws PluginException
  75          *             if the own identities can not be loaded
  76          */
  77         public Set<OwnIdentity> loadAllOwnIdentities() throws PluginException {
  78                 Reply reply = performRequest(SimpleFieldSetConstructor.create().put("Message", "GetOwnIdentities").get(), "OwnIdentities");
  79                 SimpleFieldSet fields = reply.getFields();
  80                 int ownIdentityCounter = -1;
  81                 Set<OwnIdentity> ownIdentities = new HashSet<OwnIdentity>();
  82                 while (true) {
  83                         String id = fields.get("Identity" + ++ownIdentityCounter);
  84                         if (id == null) {
  85                                 break;
  86                         }
  87                         String requestUri = fields.get("RequestURI" + ownIdentityCounter);
  88                         String insertUri = fields.get("InsertURI" + ownIdentityCounter);
  89                         String nickname = fields.get("Nickname" + ownIdentityCounter);
  90                         OwnIdentity ownIdentity = new OwnIdentity(id, nickname, requestUri, insertUri);
  91                         ownIdentity.setContexts(parseContexts("Contexts" + ownIdentityCounter, fields));
  92                         ownIdentity.setProperties(parseProperties("Properties" + ownIdentityCounter, fields));
  93                         ownIdentities.add(ownIdentity);
  94                 }
  95                 return ownIdentities;
  96         }
  97
  98         /**
  99          * Loads all identities that the given identities trusts with a score of
 100          * more than 0.
 101          *
 102          * @param ownIdentity
 103          *            The own identity
 104          * @return All trusted identities
 105          * @throws PluginException
 106          *             if an error occured talking to the Web of Trust plugin
 107          */
 108         public Set<Identity> loadTrustedIdentities(OwnIdentity ownIdentity) throws PluginException {
 109                 return loadTrustedIdentities(ownIdentity, null);
 110         }
 111
 112         /**
 113          * Loads all identities that the given identities trusts with a score of
 114          * more than 0 and the (optional) given context.
 115          *
 116          * @param ownIdentity
 117          *            The own identity
 118          * @param context
 119          *            The context to filter, or {@code null}
 120          * @return All trusted identities
 121          * @throws PluginException
 122          *             if an error occured talking to the Web of Trust plugin
 123          */
 124         public Set<Identity> loadTrustedIdentities(OwnIdentity ownIdentity, String context) throws PluginException {
 125                 Reply reply = performRequest(SimpleFieldSetConstructor.create().put("Message", "GetIdentitiesByScore").put("TreeOwner", ownIdentity.getId()).put("Selection", "+").put("Context", (context == null) ? "" : context).get(), "Identities");
 126                 SimpleFieldSet fields = reply.getFields();
 127                 Set<Identity> identities = new HashSet<Identity>();
 128                 int identityCounter = -1;
 129                 while (true) {
 130                         String id = fields.get("Identity" + ++identityCounter);
 131                         if (id == null) {
 132                                 break;
 133                         }
 134                         String nickname = fields.get("Nickname" + identityCounter);
 135                         String requestUri = fields.get("RequestURI" + identityCounter);
 136                         Identity identity = new Identity(id, nickname, requestUri);
 137                         identity.setContexts(parseContexts("Contexts" + identityCounter, fields));
 138                         identity.setProperties(parseProperties("Properties" + identityCounter, fields));
 139                         identities.add(identity);
 140                 }
 141                 return identities;
 142         }
 143
 144         /**
 145          * Adds the given context to the given identity.
 146          *
 147          * @param ownIdentity
 148          *            The identity to add the context to
 149          * @param context
 150          *            The context to add
 151          * @throws PluginException
 152          *             if an error occured talking to the Web of Trust plugin
 153          */
 154         public void addContext(OwnIdentity ownIdentity, String context) throws PluginException {
 155                 performRequest(SimpleFieldSetConstructor.create().put("Message", "AddContext").put("Identity", ownIdentity.getId()).put("Context", context).get(), "ContextAdded");
 156         }
 157
 158         /**
 159          * Removes the given context from the given identity.
 160          *
 161          * @param ownIdentity
 162          *            The identity to remove the context from
 163          * @param context
 164          *            The context to remove
 165          * @throws PluginException
 166          *             if an error occured talking to the Web of Trust plugin
 167          */
 168         public void removeContext(OwnIdentity ownIdentity, String context) throws PluginException {
 169                 performRequest(SimpleFieldSetConstructor.create().put("Message", "RemoveContext").put("Identity", ownIdentity.getId()).put("Context", context).get(), "ContextRemoved");
 170         }
 171
 172         /**
 173          * Returns the value of the property with the given name.
 174          *
 175          * @param identity
 176          *            The identity whose properties to check
 177          * @param name
 178          *            The name of the property to return
 179          * @return The value of the property, or {@code null} if there is no value
 180          * @throws PluginException
 181          *             if an error occured talking to the Web of Trust plugin
 182          */
 183         public String getProperty(Identity identity, String name) throws PluginException {
 184                 Reply reply = performRequest(SimpleFieldSetConstructor.create().put("Message", "GetProperty").put("Identity", identity.getId()).put("Property", name).get(), "PropertyValue");
 185                 return reply.getFields().get("Property");
 186         }
 187
 188         /**
 189          * Sets the property with the given name to the given value.
 190          *
 191          * @param ownIdentity
 192          *            The identity to set the property on
 193          * @param name
 194          *            The name of the property to set
 195          * @param value
 196          *            The value to set
 197          * @throws PluginException
 198          *             if an error occured talking to the Web of Trust plugin
 199          */
 200         public void setProperty(OwnIdentity ownIdentity, String name, String value) throws PluginException {
 201                 performRequest(SimpleFieldSetConstructor.create().put("Message", "SetProperty").put("Identity", ownIdentity.getId()).put("Property", name).put("Value", value).get(), "PropertyAdded");
 202         }
 203
 204         /**
 205          * Removes the property with the given name.
 206          *
 207          * @param ownIdentity
 208          *            The identity to remove the property from
 209          * @param name
 210          *            The name of the property to remove
 211          * @throws PluginException
 212          *             if an error occured talking to the Web of Trust plugin
 213          */
 214         public void removeProperty(OwnIdentity ownIdentity, String name) throws PluginException {
 215                 performRequest(SimpleFieldSetConstructor.create().put("Message", "RemoveProperty").put("Identity", ownIdentity.getId()).put("Property", name).get(), "PropertyRemoved");
 216         }
 217
 218         //
 219         // PRIVATE ACTIONS
 220         //
 221
 222         /**
 223          * Parses the contexts from the given fields.
 224          *
 225          * @param prefix
 226          *            The prefix to use to access the contexts
 227          * @param fields
 228          *            The fields to parse the contexts from
 229          * @return The parsed contexts
 230          */
 231         private Set<String> parseContexts(String prefix, SimpleFieldSet fields) {
 232                 Set<String> contexts = new HashSet<String>();
 233                 int contextCounter = -1;
 234                 while (true) {
 235                         String context = fields.get(prefix + "Context" + ++contextCounter);
 236                         if (context == null) {
 237                                 break;
 238                         }
 239                         contexts.add(context);
 240                 }
 241                 return contexts;
 242         }
 243
 244         /**
 245          * Parses the properties from the given fields.
 246          *
 247          * @param prefix
 248          *            The prefix to use to access the properties
 249          * @param fields
 250          *            The fields to parse the properties from
 251          * @return The parsed properties
 252          */
 253         private Map<String, String> parseProperties(String prefix, SimpleFieldSet fields) {
 254                 Map<String, String> properties = new HashMap<String, String>();
 255                 int propertiesCounter = -1;
 256                 while (true) {
 257                         String propertyName = fields.get(prefix + "Property" + ++propertiesCounter + "Name");
 258                         if (propertyName == null) {
 259                                 break;
 260                         }
 261                         String propertyValue = fields.get(prefix + "Property" + ++propertiesCounter + "Value");
 262                         properties.put(propertyName, propertyValue);
 263                 }
 264                 return properties;
 265         }
 266
 267         /**
 268          * Sends a request containing the given fields and waits for the target
 269          * message.
 270          *
 271          * @param fields
 272          *            The fields of the message
 273          * @param targetMessages
 274          *            The messages of the reply to wait for
 275          * @return The reply message
 276          * @throws PluginException
 277          *             if the request could not be sent
 278          */
 279         private Reply performRequest(SimpleFieldSet fields, String... targetMessages) throws PluginException {
 280                 return performRequest(fields, null, targetMessages);
 281         }
 282
 283         /**
 284          * Sends a request containing the given fields and waits for the target
 285          * message.
 286          *
 287          * @param fields
 288          *            The fields of the message
 289          * @param data
 290          *            The payload of the message
 291          * @param targetMessages
 292          *            The messages of the reply to wait for
 293          * @return The reply message
 294          * @throws PluginException
 295          *             if the request could not be sent
 296          */
 297         private Reply performRequest(SimpleFieldSet fields, Bucket data, String... targetMessages) throws PluginException {
 298                 @SuppressWarnings("synthetic-access")
 299                 Reply reply = new Reply();
 300                 for (String targetMessage : targetMessages) {
 301                         replies.put(targetMessage, reply);
 302                 }
 303                 replies.put("Error", reply);
 304                 synchronized (reply) {
 305                         pluginConnector.sendRequest(WOT_PLUGIN_NAME, PLUGIN_CONNECTION_IDENTIFIER, fields, data);
 306                         try {
 307                                 reply.wait(60000);
 308                         } catch (InterruptedException ie1) {
 309                                 logger.log(Level.WARNING, "Got interrupted while waiting for reply on GetOwnIdentities.", ie1);
 310                         }
 311                 }
 312                 for (String targetMessage : targetMessages) {
 313                         replies.remove(targetMessage);
 314                 }
 315                 replies.remove("Error");
 316                 if ((reply.getFields() != null) && reply.getFields().get("Message").equals("Error")) {
 317                         throw new PluginException("Could not perform request for " + targetMessages[0]);
 318                 }
 319                 return reply;
 320         }
 321
 322         //
 323         // INTERFACE ConnectorListener
 324         //
 325
 326         /**
 327          * {@inheritDoc}
 328          */
 329         @Override
 330         public void receivedReply(PluginConnector pluginConnector, SimpleFieldSet fields, Bucket data) {
 331                 String messageName = fields.get("Message");
 332                 Reply reply = replies.remove(messageName);
 333                 if (reply == null) {
 334                         logger.log(Level.FINE, "Not waiting for a “%s” message.", messageName);
 335                         return;
 336                 }
 337                 synchronized (reply) {
 338                         reply.setFields(fields);
 339                         reply.setData(data);
 340                         reply.notify();
 341                 }
 342         }
 343
 344         /**
 345          * Container for the data of the reply from a plugin.
 346          *
 347          * @author <a href="mailto:bombe@pterodactylus.net">David ‘Bombe’ Roden</a>
 348          */
 349         private static class Reply {
 350
 351                 /** The fields of the reply. */
 352                 private SimpleFieldSet fields;
 353
 354                 /** The payload of the reply. */
 355                 private Bucket data;
 356
 357                 /**
 358                  * Returns the fields of the reply.
 359                  *
 360                  * @return The fields of the reply
 361                  */
 362                 public SimpleFieldSet getFields() {
 363                         return fields;
 364                 }
 365
 366                 /**
 367                  * Sets the fields of the reply.
 368                  *
 369                  * @param fields
 370                  *            The fields of the reply
 371                  */
 372                 public void setFields(SimpleFieldSet fields) {
 373                         this.fields = fields;
 374                 }
 375
 376                 /**
 377                  * Returns the payload of the reply.
 378                  *
 379                  * @return The payload of the reply (may be {@code null})
 380                  */
 381                 @SuppressWarnings("unused")
 382                 public Bucket getData() {
 383                         return data;
 384                 }
 385
 386                 /**
 387                  * Sets the payload of the reply.
 388                  *
 389                  * @param data
 390                  *            The payload of the reply (may be {@code null})
 391                  */
 392                 public void setData(Bucket data) {
 393                         this.data = data;
 394                 }
 395
 396         }
 397
 398         /**
 399          * Helper method to create {@link SimpleFieldSet}s with terser code.
 400          *
 401          * @author <a href="mailto:bombe@pterodactylus.net">David ‘Bombe’ Roden</a>
 402          */
 403         private static class SimpleFieldSetConstructor {
 404
 405                 /** The field set being created. */
 406                 private SimpleFieldSet simpleFieldSet;
 407
 408                 /**
 409                  * Creates a new simple field set constructor.
 410                  *
 411                  * @param shortLived
 412                  *            {@code true} if the resulting simple field set should be
 413                  *            short-lived, {@code false} otherwise
 414                  */
 415                 private SimpleFieldSetConstructor(boolean shortLived) {
 416                         simpleFieldSet = new SimpleFieldSet(shortLived);
 417                 }
 418
 419                 //
 420                 // ACCESSORS
 421                 //
 422
 423                 /**
 424                  * Returns the created simple field set.
 425                  *
 426                  * @return The created simple field set
 427                  */
 428                 public SimpleFieldSet get() {
 429                         return simpleFieldSet;
 430                 }
 431
 432                 /**
 433                  * Sets the field with the given name to the given value.
 434                  *
 435                  * @param name
 436                  *            The name of the fleld
 437                  * @param value
 438                  *            The value of the field
 439                  * @return This constructor (for method chaining)
 440                  */
 441                 public SimpleFieldSetConstructor put(String name, String value) {
 442                         simpleFieldSet.putOverwrite(name, value);
 443                         return this;
 444                 }
 445
 446                 //
 447                 // ACTIONS
 448                 //
 449
 450                 /**
 451                  * Creates a new simple field set constructor.
 452                  *
 453                  * @return The created simple field set constructor
 454                  */
 455                 public static SimpleFieldSetConstructor create() {
 456                         return create(true);
 457                 }
 458
 459                 /**
 460                  * Creates a new simple field set constructor.
 461                  *
 462                  * @param shortLived
 463                  *            {@code true} if the resulting simple field set should be
 464                  *            short-lived, {@code false} otherwise
 465                  * @return The created simple field set constructor
 466                  */
 467                 public static SimpleFieldSetConstructor create(boolean shortLived) {
 468                         SimpleFieldSetConstructor simpleFieldSetConstructor = new SimpleFieldSetConstructor(shortLived);
 469                         return simpleFieldSetConstructor;
 470                 }
 471
 472         }
 473
 474 }