src/main/java/net/pterodactylus/wotns/freenet/wot/IdentityManager.java

   1 /*
   2  * Sone - IdentityManager.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.wotns.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.Map.Entry;
  26 import java.util.logging.Level;
  27 import java.util.logging.Logger;
  28
  29 import net.pterodactylus.util.collection.SetBuilder;
  30 import net.pterodactylus.util.logging.Logging;
  31 import net.pterodactylus.util.service.AbstractService;
  32 import net.pterodactylus.wotns.freenet.plugin.PluginException;
  33
  34 /**
  35  * The identity manager takes care of loading and storing identities, their
  36  * contexts, and properties. It does so in a way that does not expose errors via
  37  * exceptions but it only logs them and tries to return sensible defaults.
  38  * <p>
  39  * It is also responsible for polling identities from the Web of Trust plugin
  40  * and notifying registered {@link IdentityListener}s when {@link Identity}s and
  41  * {@link OwnIdentity}s are discovered or disappearing.
  42  *
  43  * @author <a href="mailto:bombe@pterodactylus.net">David ‘Bombe’ Roden</a>
  44  */
  45 public class IdentityManager extends AbstractService {
  46
  47         /** Object used for synchronization. */
  48         private final Object syncObject = new Object() {
  49                 /* inner class for better lock names. */
  50         };
  51
  52         /** The logger. */
  53         private static final Logger logger = Logging.getLogger(IdentityManager.class);
  54
  55         /** The event manager. */
  56         private final IdentityListenerManager identityListenerManager = new IdentityListenerManager();
  57
  58         /** The Web of Trust connector. */
  59         private final WebOfTrustConnector webOfTrustConnector;
  60
  61         /** The context to filter for. */
  62         private volatile String context;
  63
  64         /** The currently known own identities. */
  65         /* synchronize access on syncObject. */
  66         private Map<String, OwnIdentity> currentOwnIdentities = new HashMap<String, OwnIdentity>();
  67
  68         /** The currently trusted identities. */
  69         private Map<OwnIdentity, Set<Identity>> currentTrustedIdentities = new HashMap<OwnIdentity, Set<Identity>>();
  70
  71         /**
  72          * Creates a new identity manager.
  73          *
  74          * @param webOfTrustConnector
  75          *            The Web of Trust connector
  76          */
  77         public IdentityManager(WebOfTrustConnector webOfTrustConnector) {
  78                 super("Sone Identity Manager", false);
  79                 this.webOfTrustConnector = webOfTrustConnector;
  80         }
  81
  82         //
  83         // LISTENER MANAGEMENT
  84         //
  85
  86         /**
  87          * Adds a listener for identity events.
  88          *
  89          * @param identityListener
  90          *            The listener to add
  91          */
  92         public void addIdentityListener(IdentityListener identityListener) {
  93                 identityListenerManager.addListener(identityListener);
  94         }
  95
  96         /**
  97          * Removes a listener for identity events.
  98          *
  99          * @param identityListener
 100          *            The listener to remove
 101          */
 102         public void removeIdentityListener(IdentityListener identityListener) {
 103                 identityListenerManager.removeListener(identityListener);
 104         }
 105
 106         //
 107         // ACCESSORS
 108         //
 109
 110         /**
 111          * Sets the context to filter own identities and trusted identities for.
 112          *
 113          * @param context
 114          *            The context to filter for, or {@code null} to not filter
 115          */
 116         public void setContext(String context) {
 117                 this.context = context;
 118         }
 119
 120         /**
 121          * Returns whether the Web of Trust plugin could be reached during the last
 122          * try.
 123          *
 124          * @return {@code true} if the Web of Trust plugin is connected, {@code
 125          *         false} otherwise
 126          */
 127         public boolean isConnected() {
 128                 try {
 129                         webOfTrustConnector.ping();
 130                         return true;
 131                 } catch (PluginException pe1) {
 132                         /* not connected, ignore. */
 133                         return false;
 134                 }
 135         }
 136
 137         /**
 138          * Returns the own identity with the given ID.
 139          *
 140          * @param id
 141          *            The ID of the own identity
 142          * @return The own identity, or {@code null} if there is no such identity
 143          */
 144         public OwnIdentity getOwnIdentity(String id) {
 145                 Set<OwnIdentity> allOwnIdentities = getAllOwnIdentities();
 146                 for (OwnIdentity ownIdentity : allOwnIdentities) {
 147                         if (ownIdentity.getId().equals(id)) {
 148                                 return ownIdentity;
 149                         }
 150                 }
 151                 return null;
 152         }
 153
 154         /**
 155          * Returns all own identities.
 156          *
 157          * @return All own identities
 158          */
 159         public Set<OwnIdentity> getAllOwnIdentities() {
 160                 try {
 161                         Set<OwnIdentity> ownIdentities = webOfTrustConnector.loadAllOwnIdentities();
 162                         Map<String, OwnIdentity> newOwnIdentities = new HashMap<String, OwnIdentity>();
 163                         for (OwnIdentity ownIdentity : ownIdentities) {
 164                                 newOwnIdentities.put(ownIdentity.getId(), ownIdentity);
 165                         }
 166                         checkOwnIdentities(newOwnIdentities);
 167                         return ownIdentities;
 168                 } catch (WebOfTrustException wote1) {
 169                         logger.log(Level.WARNING, "Could not load all own identities!", wote1);
 170                         return Collections.emptySet();
 171                 }
 172         }
 173
 174         public Set<Identity> getTrustedIdentities(OwnIdentity ownIdentity) {
 175                 SetBuilder<Identity> identities = new SetBuilder<Identity>();
 176                 if ((context == null) || ownIdentity.getContexts().contains(context)) {
 177                         identities.add(ownIdentity);
 178                 }
 179                 synchronized (syncObject) {
 180                         identities.addAll(currentTrustedIdentities.get(ownIdentity));
 181                 }
 182                 return identities.get();
 183         }
 184
 185         //
 186         // SERVICE METHODS
 187         //
 188
 189         /**
 190          * {@inheritDoc}
 191          */
 192         @Override
 193         protected void serviceRun() {
 194                 Map<OwnIdentity, Map<String, Identity>> oldIdentities = Collections.emptyMap();
 195                 while (!shouldStop()) {
 196                         Map<OwnIdentity, Map<String, Identity>> currentIdentities = new HashMap<OwnIdentity, Map<String, Identity>>();
 197                         @SuppressWarnings("hiding")
 198                         Map<String, OwnIdentity> currentOwnIdentities = new HashMap<String, OwnIdentity>();
 199
 200                         Set<OwnIdentity> ownIdentities = null;
 201                         boolean identitiesLoaded = false;
 202                         try {
 203                                 /* get all identities with the wanted context from WoT. */
 204                                 ownIdentities = webOfTrustConnector.loadAllOwnIdentities();
 205
 206                                 /* load trusted identities. */
 207                                 for (OwnIdentity ownIdentity : ownIdentities) {
 208                                         if ((context != null) && !ownIdentity.hasContext(context)) {
 209                                                 continue;
 210                                         }
 211                                         currentOwnIdentities.put(ownIdentity.getId(), ownIdentity);
 212
 213                                         Set<Identity> trustedIdentities = webOfTrustConnector.loadTrustedIdentities(ownIdentity, context);
 214                                         Map<String, Identity> identities = new HashMap<String, Identity>();
 215                                         currentIdentities.put(ownIdentity, identities);
 216                                         for (Identity identity : trustedIdentities) {
 217                                                 identities.put(identity.getId(), identity);
 218                                         }
 219                                 }
 220                                 identitiesLoaded = true;
 221                         } catch (WebOfTrustException wote1) {
 222                                 logger.log(Level.WARNING, "WoT has disappeared!", wote1);
 223                         }
 224
 225                         if (identitiesLoaded) {
 226
 227                                 /* check for changes. */
 228                                 checkOwnIdentities(currentOwnIdentities);
 229
 230                                 /* now check for changes in remote identities. */
 231                                 for (OwnIdentity ownIdentity : currentOwnIdentities.values()) {
 232
 233                                         /* find new identities. */
 234                                         for (Identity currentIdentity : currentIdentities.get(ownIdentity).values()) {
 235                                                 if (!oldIdentities.containsKey(ownIdentity) || !oldIdentities.get(ownIdentity).containsKey(currentIdentity.getId())) {
 236                                                         identityListenerManager.fireIdentityAdded(ownIdentity, currentIdentity);
 237                                                 }
 238                                         }
 239
 240                                         /* find removed identities. */
 241                                         if (oldIdentities.containsKey(ownIdentity)) {
 242                                                 for (Identity oldIdentity : oldIdentities.get(ownIdentity).values()) {
 243                                                         if (!currentIdentities.get(ownIdentity).containsKey(oldIdentity.getId())) {
 244                                                                 identityListenerManager.fireIdentityRemoved(ownIdentity, oldIdentity);
 245                                                         }
 246                                                 }
 247
 248                                                 /* check for changes in the contexts. */
 249                                                 for (Identity oldIdentity : oldIdentities.get(ownIdentity).values()) {
 250                                                         if (!currentIdentities.get(ownIdentity).containsKey(oldIdentity.getId())) {
 251                                                                 continue;
 252                                                         }
 253                                                         Identity newIdentity = currentIdentities.get(ownIdentity).get(oldIdentity.getId());
 254                                                         Set<String> oldContexts = oldIdentity.getContexts();
 255                                                         Set<String> newContexts = newIdentity.getContexts();
 256                                                         if (oldContexts.size() != newContexts.size()) {
 257                                                                 identityListenerManager.fireIdentityUpdated(ownIdentity, newIdentity);
 258                                                                 continue;
 259                                                         }
 260                                                         for (String oldContext : oldContexts) {
 261                                                                 if (!newContexts.contains(oldContext)) {
 262                                                                         identityListenerManager.fireIdentityUpdated(ownIdentity, newIdentity);
 263                                                                         break;
 264                                                                 }
 265                                                         }
 266                                                 }
 267
 268                                                 /* check for changes in the properties. */
 269                                                 for (Identity oldIdentity : oldIdentities.get(ownIdentity).values()) {
 270                                                         if (!currentIdentities.get(ownIdentity).containsKey(oldIdentity.getId())) {
 271                                                                 continue;
 272                                                         }
 273                                                         Identity newIdentity = currentIdentities.get(ownIdentity).get(oldIdentity.getId());
 274                                                         Map<String, String> oldProperties = oldIdentity.getProperties();
 275                                                         Map<String, String> newProperties = newIdentity.getProperties();
 276                                                         if (oldProperties.size() != newProperties.size()) {
 277                                                                 identityListenerManager.fireIdentityUpdated(ownIdentity, newIdentity);
 278                                                                 continue;
 279                                                         }
 280                                                         for (Entry<String, String> oldProperty : oldProperties.entrySet()) {
 281                                                                 if (!newProperties.containsKey(oldProperty.getKey()) || !newProperties.get(oldProperty.getKey()).equals(oldProperty.getValue())) {
 282                                                                         identityListenerManager.fireIdentityUpdated(ownIdentity, newIdentity);
 283                                                                         break;
 284                                                                 }
 285                                                         }
 286                                                 }
 287                                         }
 288                                 }
 289
 290                                 /* remember the current set of identities. */
 291                                 oldIdentities = currentIdentities;
 292                                 synchronized (syncObject) {
 293                                         currentTrustedIdentities.clear();
 294                                         for (Entry<OwnIdentity, Map<String, Identity>> entry : currentIdentities.entrySet()) {
 295                                                 Set<Identity> identities = new HashSet<Identity>();
 296                                                 currentTrustedIdentities.put(entry.getKey(), identities);
 297                                                 for (Identity identity : entry.getValue().values()) {
 298                                                         identities.add(identity);
 299                                                 }
 300                                         }
 301                                 }
 302                         }
 303
 304                         /* wait a minute before checking again. */
 305                         sleep(60 * 1000);
 306                 }
 307         }
 308
 309         //
 310         // PRIVATE METHODS
 311         //
 312
 313         /**
 314          * Checks the given new list of own identities for added or removed own
 315          * identities, as compared to {@link #currentOwnIdentities}.
 316          *
 317          * @param newOwnIdentities
 318          *            The new own identities
 319          */
 320         private void checkOwnIdentities(Map<String, OwnIdentity> newOwnIdentities) {
 321                 synchronized (syncObject) {
 322
 323                         /* find removed own identities: */
 324                         for (OwnIdentity oldOwnIdentity : currentOwnIdentities.values()) {
 325                                 if (!newOwnIdentities.containsKey(oldOwnIdentity.getId())) {
 326                                         identityListenerManager.fireOwnIdentityRemoved(oldOwnIdentity);
 327                                 }
 328                         }
 329
 330                         /* find added own identities. */
 331                         for (OwnIdentity currentOwnIdentity : newOwnIdentities.values()) {
 332                                 if (!currentOwnIdentities.containsKey(currentOwnIdentity.getId())) {
 333                                         identityListenerManager.fireOwnIdentityAdded(currentOwnIdentity);
 334                                 }
 335                         }
 336
 337                         currentOwnIdentities.clear();
 338                         currentOwnIdentities.putAll(newOwnIdentities);
 339                 }
 340         }
 341
 342 }