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