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.sone.freenet.wot;
  19
  20 import java.util.Collections;
  21 import java.util.HashMap;
  22 import java.util.Map;
  23 import java.util.Map.Entry;
  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.PluginException;
  29 import net.pterodactylus.util.logging.Logging;
  30 import net.pterodactylus.util.service.AbstractService;
  31
  32 /**
  33  * The identity manager takes care of loading and storing identities, their
  34  * contexts, and properties. It does so in a way that does not expose errors via
  35  * exceptions but it only logs them and tries to return sensible defaults.
  36  * <p>
  37  * It is also responsible for polling identities from the Web of Trust plugin
  38  * and notifying registered {@link IdentityListener}s when {@link Identity}s and
  39  * {@link OwnIdentity}s are discovered or disappearing.
  40  *
  41  * @author <a href="mailto:bombe@pterodactylus.net">David ‘Bombe’ Roden</a>
  42  */
  43 public class IdentityManager extends AbstractService {
  44
  45         /** Object used for synchronization. */
  46         private final Object syncObject = new Object() {
  47                 /* inner class for better lock names. */
  48         };
  49
  50         /** The logger. */
  51         private static final Logger logger = Logging.getLogger(IdentityManager.class);
  52
  53         /** The event manager. */
  54         private final IdentityListenerManager identityListenerManager = new IdentityListenerManager();
  55
  56         /** The Web of Trust connector. */
  57         private final WebOfTrustConnector webOfTrustConnector;
  58
  59         /** The context to filter for. */
  60         private volatile String context;
  61
  62         /** The currently known own identities. */
  63         /* synchronize access on syncObject. */
  64         private Map<String, OwnIdentity> currentOwnIdentities = new HashMap<String, OwnIdentity>();
  65
  66         /**
  67          * Creates a new identity manager.
  68          *
  69          * @param webOfTrustConnector
  70          *            The Web of Trust connector
  71          */
  72         public IdentityManager(WebOfTrustConnector webOfTrustConnector) {
  73                 super("Sone Identity Manager", false);
  74                 this.webOfTrustConnector = webOfTrustConnector;
  75         }
  76
  77         //
  78         // LISTENER MANAGEMENT
  79         //
  80
  81         /**
  82          * Adds a listener for identity events.
  83          *
  84          * @param identityListener
  85          *            The listener to add
  86          */
  87         public void addIdentityListener(IdentityListener identityListener) {
  88                 identityListenerManager.addListener(identityListener);
  89         }
  90
  91         /**
  92          * Removes a listener for identity events.
  93          *
  94          * @param identityListener
  95          *            The listener to remove
  96          */
  97         public void removeIdentityListener(IdentityListener identityListener) {
  98                 identityListenerManager.removeListener(identityListener);
  99         }
 100
 101         //
 102         // ACCESSORS
 103         //
 104
 105         /**
 106          * Sets the context to filter own identities and trusted identities for.
 107          *
 108          * @param context
 109          *            The context to filter for, or {@code null} to not filter
 110          */
 111         public void setContext(String context) {
 112                 this.context = context;
 113         }
 114
 115         /**
 116          * Returns whether the Web of Trust plugin could be reached during the last
 117          * try.
 118          *
 119          * @return {@code true} if the Web of Trust plugin is connected,
 120          *         {@code false} otherwise
 121          */
 122         public boolean isConnected() {
 123                 try {
 124                         webOfTrustConnector.ping();
 125                         return true;
 126                 } catch (PluginException pe1) {
 127                         /* not connected, ignore. */
 128                         return false;
 129                 }
 130         }
 131
 132         /**
 133          * Returns the own identity with the given ID.
 134          *
 135          * @param id
 136          *            The ID of the own identity
 137          * @return The own identity, or {@code null} if there is no such identity
 138          */
 139         public OwnIdentity getOwnIdentity(String id) {
 140                 Set<OwnIdentity> allOwnIdentities = getAllOwnIdentities();
 141                 for (OwnIdentity ownIdentity : allOwnIdentities) {
 142                         if (ownIdentity.getId().equals(id)) {
 143                                 return ownIdentity;
 144                         }
 145                 }
 146                 return null;
 147         }
 148
 149         /**
 150          * Returns all own identities.
 151          *
 152          * @return All own identities
 153          */
 154         public Set<OwnIdentity> getAllOwnIdentities() {
 155                 try {
 156                         Set<OwnIdentity> ownIdentities = webOfTrustConnector.loadAllOwnIdentities();
 157                         Map<String, OwnIdentity> newOwnIdentities = new HashMap<String, OwnIdentity>();
 158                         for (OwnIdentity ownIdentity : ownIdentities) {
 159                                 newOwnIdentities.put(ownIdentity.getId(), ownIdentity);
 160                         }
 161                         checkOwnIdentities(newOwnIdentities);
 162                         return ownIdentities;
 163                 } catch (WebOfTrustException wote1) {
 164                         logger.log(Level.WARNING, "Could not load all own identities!", wote1);
 165                         return Collections.emptySet();
 166                 }
 167         }
 168
 169         //
 170         // SERVICE METHODS
 171         //
 172
 173         /**
 174          * {@inheritDoc}
 175          */
 176         @Override
 177         protected void serviceRun() {
 178                 Map<OwnIdentity, Map<String, Identity>> oldIdentities = Collections.emptyMap();
 179                 while (!shouldStop()) {
 180                         Map<OwnIdentity, Map<String, Identity>> currentIdentities = new HashMap<OwnIdentity, Map<String, Identity>>();
 181                         Map<String, OwnIdentity> currentOwnIdentities = new HashMap<String, OwnIdentity>();
 182
 183                         try {
 184                                 /* get all identities with the wanted context from WoT. */
 185                                 Set<OwnIdentity> ownIdentities = webOfTrustConnector.loadAllOwnIdentities();
 186
 187                                 /* check for changes. */
 188                                 for (OwnIdentity ownIdentity : ownIdentities) {
 189                                         currentOwnIdentities.put(ownIdentity.getId(), ownIdentity);
 190                                 }
 191                                 checkOwnIdentities(currentOwnIdentities);
 192
 193                                 /* now filter for context and get all identities. */
 194                                 for (OwnIdentity ownIdentity : ownIdentities) {
 195                                         if ((context != null) && !ownIdentity.hasContext(context)) {
 196                                                 continue;
 197                                         }
 198
 199                                         Set<Identity> trustedIdentities = webOfTrustConnector.loadTrustedIdentities(ownIdentity, context);
 200                                         Map<String, Identity> identities = new HashMap<String, Identity>();
 201                                         currentIdentities.put(ownIdentity, identities);
 202                                         for (Identity identity : trustedIdentities) {
 203                                                 identities.put(identity.getId(), identity);
 204                                         }
 205
 206                                         /* find new identities. */
 207                                         for (Identity currentIdentity : currentIdentities.get(ownIdentity).values()) {
 208                                                 if (!oldIdentities.containsKey(ownIdentity) || !oldIdentities.get(ownIdentity).containsKey(currentIdentity.getId())) {
 209                                                         identityListenerManager.fireIdentityAdded(ownIdentity, currentIdentity);
 210                                                 }
 211                                         }
 212
 213                                         /* find removed identities. */
 214                                         if (oldIdentities.containsKey(ownIdentity)) {
 215                                                 for (Identity oldIdentity : oldIdentities.get(ownIdentity).values()) {
 216                                                         if (!currentIdentities.get(ownIdentity).containsKey(oldIdentity.getId())) {
 217                                                                 identityListenerManager.fireIdentityRemoved(ownIdentity, oldIdentity);
 218                                                         }
 219                                                 }
 220
 221                                                 /* check for changes in the contexts. */
 222                                                 for (Identity oldIdentity : oldIdentities.get(ownIdentity).values()) {
 223                                                         if (!currentIdentities.get(ownIdentity).containsKey(oldIdentity.getId())) {
 224                                                                 continue;
 225                                                         }
 226                                                         Identity newIdentity = currentIdentities.get(ownIdentity).get(oldIdentity.getId());
 227                                                         Set<String> oldContexts = oldIdentity.getContexts();
 228                                                         Set<String> newContexts = newIdentity.getContexts();
 229                                                         if (oldContexts.size() != newContexts.size()) {
 230                                                                 identityListenerManager.fireIdentityUpdated(ownIdentity, newIdentity);
 231                                                                 continue;
 232                                                         }
 233                                                         for (String oldContext : oldContexts) {
 234                                                                 if (!newContexts.contains(oldContext)) {
 235                                                                         identityListenerManager.fireIdentityUpdated(ownIdentity, newIdentity);
 236                                                                         break;
 237                                                                 }
 238                                                         }
 239                                                 }
 240
 241                                                 /* check for changes in the properties. */
 242                                                 for (Identity oldIdentity : oldIdentities.get(ownIdentity).values()) {
 243                                                         if (!currentIdentities.get(ownIdentity).containsKey(oldIdentity.getId())) {
 244                                                                 continue;
 245                                                         }
 246                                                         Identity newIdentity = currentIdentities.get(ownIdentity).get(oldIdentity.getId());
 247                                                         Map<String, String> oldProperties = oldIdentity.getProperties();
 248                                                         Map<String, String> newProperties = newIdentity.getProperties();
 249                                                         if (oldProperties.size() != newProperties.size()) {
 250                                                                 identityListenerManager.fireIdentityUpdated(ownIdentity, newIdentity);
 251                                                                 continue;
 252                                                         }
 253                                                         for (Entry<String, String> oldProperty : oldProperties.entrySet()) {
 254                                                                 if (!newProperties.containsKey(oldProperty.getKey()) || !newProperties.get(oldProperty.getKey()).equals(oldProperty.getValue())) {
 255                                                                         identityListenerManager.fireIdentityUpdated(ownIdentity, newIdentity);
 256                                                                         break;
 257                                                                 }
 258                                                         }
 259                                                 }
 260                                         }
 261
 262                                         /* remember the current set of identities. */
 263                                         oldIdentities = currentIdentities;
 264                                 }
 265
 266                         } catch (WebOfTrustException wote1) {
 267                                 logger.log(Level.WARNING, "WoT has disappeared!", wote1);
 268                         }
 269
 270                         /* wait a minute before checking again. */
 271                         sleep(60 * 1000);
 272                 }
 273         }
 274
 275         //
 276         // PRIVATE METHODS
 277         //
 278
 279         /**
 280          * Checks the given new list of own identities for added or removed own
 281          * identities, as compared to {@link #currentOwnIdentities}.
 282          *
 283          * @param newOwnIdentities
 284          *            The new own identities
 285          */
 286         private void checkOwnIdentities(Map<String, OwnIdentity> newOwnIdentities) {
 287                 synchronized (syncObject) {
 288
 289                         /* find removed own identities: */
 290                         for (OwnIdentity oldOwnIdentity : currentOwnIdentities.values()) {
 291                                 if (!newOwnIdentities.containsKey(oldOwnIdentity.getId())) {
 292                                         identityListenerManager.fireOwnIdentityRemoved(oldOwnIdentity);
 293                                 }
 294                         }
 295
 296                         /* find added own identities. */
 297                         for (OwnIdentity currentOwnIdentity : newOwnIdentities.values()) {
 298                                 if (!currentOwnIdentities.containsKey(currentOwnIdentity.getId())) {
 299                                         identityListenerManager.fireOwnIdentityAdded(currentOwnIdentity);
 300                                 }
 301                         }
 302
 303                         currentOwnIdentities.clear();
 304                         currentOwnIdentities.putAll(newOwnIdentities);
 305                 }
 306         }
 307
 308 }