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

   1 /*
   2  * Sone - IdentityManager.java - Copyright © 2010–2012 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.Map.Entry;
  25 import java.util.Set;
  26 import java.util.logging.Level;
  27 import java.util.logging.Logger;
  28
  29 import net.pterodactylus.sone.freenet.plugin.PluginException;
  30 import net.pterodactylus.util.logging.Logging;
  31 import net.pterodactylus.util.service.AbstractService;
  32
  33 /**
  34  * The identity manager takes care of loading and storing identities, their
  35  * contexts, and properties. It does so in a way that does not expose errors via
  36  * exceptions but it only logs them and tries to return sensible defaults.
  37  * <p>
  38  * It is also responsible for polling identities from the Web of Trust plugin
  39  * and notifying registered {@link IdentityListener}s when {@link Identity}s and
  40  * {@link OwnIdentity}s are discovered or disappearing.
  41  *
  42  * @author <a href="mailto:bombe@pterodactylus.net">David ‘Bombe’ Roden</a>
  43  */
  44 public class IdentityManager extends AbstractService {
  45
  46         /** Object used for synchronization. */
  47         @SuppressWarnings("hiding")
  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         /**
  69          * Creates a new identity manager.
  70          *
  71          * @param webOfTrustConnector
  72          *            The Web of Trust connector
  73          */
  74         public IdentityManager(WebOfTrustConnector webOfTrustConnector) {
  75                 super("Sone Identity Manager", false);
  76                 this.webOfTrustConnector = webOfTrustConnector;
  77         }
  78
  79         //
  80         // LISTENER MANAGEMENT
  81         //
  82
  83         /**
  84          * Adds a listener for identity events.
  85          *
  86          * @param identityListener
  87          *            The listener to add
  88          */
  89         public void addIdentityListener(IdentityListener identityListener) {
  90                 identityListenerManager.addListener(identityListener);
  91         }
  92
  93         /**
  94          * Removes a listener for identity events.
  95          *
  96          * @param identityListener
  97          *            The listener to remove
  98          */
  99         public void removeIdentityListener(IdentityListener identityListener) {
 100                 identityListenerManager.removeListener(identityListener);
 101         }
 102
 103         //
 104         // ACCESSORS
 105         //
 106
 107         /**
 108          * Sets the context to filter own identities and trusted identities for.
 109          *
 110          * @param context
 111          *            The context to filter for, or {@code null} to not filter
 112          */
 113         public void setContext(String context) {
 114                 this.context = context;
 115         }
 116
 117         /**
 118          * Returns whether the Web of Trust plugin could be reached during the last
 119          * try.
 120          *
 121          * @return {@code true} if the Web of Trust plugin is connected,
 122          *         {@code false} otherwise
 123          */
 124         public boolean isConnected() {
 125                 try {
 126                         webOfTrustConnector.ping();
 127                         return true;
 128                 } catch (PluginException pe1) {
 129                         /* not connected, ignore. */
 130                         return false;
 131                 }
 132         }
 133
 134         /**
 135          * Returns the own identity with the given ID.
 136          *
 137          * @param id
 138          *            The ID of the own identity
 139          * @return The own identity, or {@code null} if there is no such identity
 140          */
 141         public OwnIdentity getOwnIdentity(String id) {
 142                 Set<OwnIdentity> allOwnIdentities = getAllOwnIdentities();
 143                 for (OwnIdentity ownIdentity : allOwnIdentities) {
 144                         if (ownIdentity.getId().equals(id)) {
 145                                 return new DefaultOwnIdentity(ownIdentity);
 146                         }
 147                 }
 148                 return null;
 149         }
 150
 151         /**
 152          * Returns all own identities.
 153          *
 154          * @return All own identities
 155          */
 156         public Set<OwnIdentity> getAllOwnIdentities() {
 157                 return new HashSet<OwnIdentity>(currentOwnIdentities.values());
 158         }
 159
 160         //
 161         // SERVICE METHODS
 162         //
 163
 164         /**
 165          * {@inheritDoc}
 166          */
 167         @Override
 168         protected void serviceRun() {
 169                 Map<OwnIdentity, Map<String, Identity>> oldIdentities = Collections.emptyMap();
 170                 while (!shouldStop()) {
 171                         Map<OwnIdentity, Map<String, Identity>> currentIdentities = new HashMap<OwnIdentity, Map<String, Identity>>();
 172                         Map<String, OwnIdentity> currentOwnIdentities = new HashMap<String, OwnIdentity>();
 173
 174                         Set<OwnIdentity> ownIdentities = null;
 175                         boolean identitiesLoaded = false;
 176                         try {
 177                                 /* get all identities with the wanted context from WoT. */
 178                                 ownIdentities = webOfTrustConnector.loadAllOwnIdentities();
 179
 180                                 /* load trusted identities. */
 181                                 for (OwnIdentity ownIdentity : ownIdentities) {
 182                                         if ((context != null) && !ownIdentity.hasContext(context)) {
 183                                                 continue;
 184                                         }
 185                                         currentOwnIdentities.put(ownIdentity.getId(), ownIdentity);
 186
 187                                         Set<Identity> trustedIdentities = webOfTrustConnector.loadTrustedIdentities(ownIdentity, context);
 188                                         Map<String, Identity> identities = new HashMap<String, Identity>();
 189                                         currentIdentities.put(ownIdentity, identities);
 190                                         for (Identity identity : trustedIdentities) {
 191                                                 identities.put(identity.getId(), identity);
 192                                         }
 193                                 }
 194                                 identitiesLoaded = true;
 195                         } catch (WebOfTrustException wote1) {
 196                                 logger.log(Level.WARNING, "WoT has disappeared!", wote1);
 197                         }
 198
 199                         if (identitiesLoaded) {
 200
 201                                 /* check for changes. */
 202                                 checkOwnIdentities(currentOwnIdentities);
 203
 204                                 /* now check for changes in remote identities. */
 205                                 for (OwnIdentity ownIdentity : currentOwnIdentities.values()) {
 206
 207                                         /* find new identities. */
 208                                         for (Identity currentIdentity : currentIdentities.get(ownIdentity).values()) {
 209                                                 if (!oldIdentities.containsKey(ownIdentity) || !oldIdentities.get(ownIdentity).containsKey(currentIdentity.getId())) {
 210                                                         identityListenerManager.fireIdentityAdded(ownIdentity, currentIdentity);
 211                                                 }
 212                                         }
 213
 214                                         /* find removed identities. */
 215                                         if (oldIdentities.containsKey(ownIdentity)) {
 216                                                 for (Identity oldIdentity : oldIdentities.get(ownIdentity).values()) {
 217                                                         if (!currentIdentities.get(ownIdentity).containsKey(oldIdentity.getId())) {
 218                                                                 identityListenerManager.fireIdentityRemoved(ownIdentity, oldIdentity);
 219                                                         }
 220                                                 }
 221
 222                                                 /* check for changes in the contexts. */
 223                                                 for (Identity oldIdentity : oldIdentities.get(ownIdentity).values()) {
 224                                                         if (!currentIdentities.get(ownIdentity).containsKey(oldIdentity.getId())) {
 225                                                                 continue;
 226                                                         }
 227                                                         Identity newIdentity = currentIdentities.get(ownIdentity).get(oldIdentity.getId());
 228                                                         Set<String> oldContexts = oldIdentity.getContexts();
 229                                                         Set<String> newContexts = newIdentity.getContexts();
 230                                                         if (oldContexts.size() != newContexts.size()) {
 231                                                                 identityListenerManager.fireIdentityUpdated(ownIdentity, newIdentity);
 232                                                                 continue;
 233                                                         }
 234                                                         for (String oldContext : oldContexts) {
 235                                                                 if (!newContexts.contains(oldContext)) {
 236                                                                         identityListenerManager.fireIdentityUpdated(ownIdentity, newIdentity);
 237                                                                         break;
 238                                                                 }
 239                                                         }
 240                                                 }
 241
 242                                                 /* check for changes in the properties. */
 243                                                 for (Identity oldIdentity : oldIdentities.get(ownIdentity).values()) {
 244                                                         if (!currentIdentities.get(ownIdentity).containsKey(oldIdentity.getId())) {
 245                                                                 continue;
 246                                                         }
 247                                                         Identity newIdentity = currentIdentities.get(ownIdentity).get(oldIdentity.getId());
 248                                                         Map<String, String> oldProperties = oldIdentity.getProperties();
 249                                                         Map<String, String> newProperties = newIdentity.getProperties();
 250                                                         if (oldProperties.size() != newProperties.size()) {
 251                                                                 identityListenerManager.fireIdentityUpdated(ownIdentity, newIdentity);
 252                                                                 continue;
 253                                                         }
 254                                                         for (Entry<String, String> oldProperty : oldProperties.entrySet()) {
 255                                                                 if (!newProperties.containsKey(oldProperty.getKey()) || !newProperties.get(oldProperty.getKey()).equals(oldProperty.getValue())) {
 256                                                                         identityListenerManager.fireIdentityUpdated(ownIdentity, newIdentity);
 257                                                                         break;
 258                                                                 }
 259                                                         }
 260                                                 }
 261                                         }
 262                                 }
 263
 264                                 /* remember the current set of identities. */
 265                                 oldIdentities = currentIdentities;
 266                         }
 267
 268                         /* wait a minute before checking again. */
 269                         sleep(60 * 1000);
 270                 }
 271         }
 272
 273         //
 274         // PRIVATE METHODS
 275         //
 276
 277         /**
 278          * Checks the given new list of own identities for added or removed own
 279          * identities, as compared to {@link #currentOwnIdentities}.
 280          *
 281          * @param newOwnIdentities
 282          *            The new own identities
 283          */
 284         private void checkOwnIdentities(Map<String, OwnIdentity> newOwnIdentities) {
 285                 synchronized (syncObject) {
 286
 287                         /* find removed own identities: */
 288                         for (OwnIdentity oldOwnIdentity : currentOwnIdentities.values()) {
 289                                 OwnIdentity newOwnIdentity = newOwnIdentities.get(oldOwnIdentity.getId());
 290                                 if ((newOwnIdentity == null) || ((context != null) && oldOwnIdentity.hasContext(context) && !newOwnIdentity.hasContext(context))) {
 291                                         identityListenerManager.fireOwnIdentityRemoved(new DefaultOwnIdentity(oldOwnIdentity));
 292                                 }
 293                         }
 294
 295                         /* find added own identities. */
 296                         for (OwnIdentity currentOwnIdentity : newOwnIdentities.values()) {
 297                                 OwnIdentity oldOwnIdentity = currentOwnIdentities.get(currentOwnIdentity.getId());
 298                                 if (((oldOwnIdentity == null) && ((context == null) || currentOwnIdentity.hasContext(context))) || ((oldOwnIdentity != null) && (context != null) && (!oldOwnIdentity.hasContext(context) && currentOwnIdentity.hasContext(context)))) {
 299                                         identityListenerManager.fireOwnIdentityAdded(new DefaultOwnIdentity(currentOwnIdentity));
 300                                 }
 301                         }
 302
 303                         currentOwnIdentities.clear();
 304                         currentOwnIdentities.putAll(newOwnIdentities);
 305                 }
 306         }
 307
 308 }