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