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

   1 /*
   2  * Sone - IdentityManager.java - Copyright © 2010–2013 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 static com.google.common.collect.HashMultimap.create;
  21
  22 import java.util.Collection;
  23 import java.util.HashSet;
  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.sone.freenet.wot.IdentityChangeDetector.IdentityProcessor;
  30 import net.pterodactylus.sone.freenet.wot.event.IdentityAddedEvent;
  31 import net.pterodactylus.sone.freenet.wot.event.IdentityRemovedEvent;
  32 import net.pterodactylus.sone.freenet.wot.event.IdentityUpdatedEvent;
  33 import net.pterodactylus.sone.freenet.wot.event.OwnIdentityAddedEvent;
  34 import net.pterodactylus.sone.freenet.wot.event.OwnIdentityRemovedEvent;
  35 import net.pterodactylus.util.logging.Logging;
  36 import net.pterodactylus.util.service.AbstractService;
  37
  38 import com.google.common.collect.Multimap;
  39 import com.google.common.collect.Sets;
  40 import com.google.common.eventbus.EventBus;
  41 import com.google.inject.Inject;
  42 import com.google.inject.name.Named;
  43
  44 /**
  45  * The identity manager takes care of loading and storing identities, their
  46  * contexts, and properties. It does so in a way that does not expose errors via
  47  * exceptions but it only logs them and tries to return sensible defaults.
  48  * <p/>
  49  * It is also responsible for polling identities from the Web of Trust plugin
  50  * and sending events to the {@link EventBus} when {@link Identity}s and {@link
  51  * OwnIdentity}s are discovered or disappearing.
  52  *
  53  * @author <a href="mailto:bombe@pterodactylus.net">David ‘Bombe’ Roden</a>
  54  */
  55 public class IdentityManager extends AbstractService {
  56
  57         /** Object used for synchronization. */
  58         @SuppressWarnings("hiding")
  59         private final Object syncObject = new Object() {
  60                 /* inner class for better lock names. */
  61         };
  62
  63         /** The logger. */
  64         private static final Logger logger = Logging.getLogger(IdentityManager.class);
  65
  66         /** The event bus. */
  67         private final EventBus eventBus;
  68
  69         /** The Web of Trust connector. */
  70         private final WebOfTrustConnector webOfTrustConnector;
  71
  72         /** The context to filter for. */
  73         private final String context;
  74
  75         /** The currently known own identities. */
  76         /* synchronize access on syncObject. */
  77         private final Set<OwnIdentity> currentOwnIdentities = Sets.newHashSet();
  78
  79         /**
  80          * Creates a new identity manager.
  81          *
  82          * @param eventBus
  83          *              The event bus
  84          * @param webOfTrustConnector
  85          *              The Web of Trust connector
  86          * @param context
  87          *              The context to focus on (may be {@code null} to ignore contexts)
  88          */
  89         @Inject
  90         public IdentityManager(EventBus eventBus, WebOfTrustConnector webOfTrustConnector, @Named("WebOfTrustContext") String context) {
  91                 super("Sone Identity Manager", false);
  92                 this.eventBus = eventBus;
  93                 this.webOfTrustConnector = webOfTrustConnector;
  94                 this.context = context;
  95         }
  96
  97         //
  98         // ACCESSORS
  99         //
 100
 101         /**
 102          * Returns whether the Web of Trust plugin could be reached during the last
 103          * try.
 104          *
 105          * @return {@code true} if the Web of Trust plugin is connected, {@code false}
 106          *         otherwise
 107          */
 108         public boolean isConnected() {
 109                 try {
 110                         webOfTrustConnector.ping();
 111                         return true;
 112                 } catch (PluginException pe1) {
 113                         /* not connected, ignore. */
 114                         return false;
 115                 }
 116         }
 117
 118         /**
 119          * Returns all own identities.
 120          *
 121          * @return All own identities
 122          */
 123         public Set<OwnIdentity> getAllOwnIdentities() {
 124                 synchronized (syncObject) {
 125                         return new HashSet<OwnIdentity>(currentOwnIdentities);
 126                 }
 127         }
 128
 129         //
 130         // SERVICE METHODS
 131         //
 132
 133         @Override
 134         protected void serviceRun() {
 135                 Multimap<OwnIdentity, Identity> oldIdentities = create();
 136
 137                 while (!shouldStop()) {
 138                         try {
 139                                 Collection<OwnIdentity> currentOwnIdentities = webOfTrustConnector.loadAllOwnIdentities();
 140                                 Multimap<OwnIdentity, Identity> currentIdentities = loadTrustedIdentitiesForOwnIdentities(currentOwnIdentities);
 141
 142                                 detectChangesInIdentities(currentOwnIdentities, currentIdentities, oldIdentities);
 143                                 oldIdentities = currentIdentities;
 144
 145                                 synchronized (syncObject) {
 146                                         this.currentOwnIdentities.clear();
 147                                         this.currentOwnIdentities.addAll(currentOwnIdentities);
 148                                 }
 149                         } catch (WebOfTrustException wote1) {
 150                                 logger.log(Level.WARNING, "WoT has disappeared!", wote1);
 151                         }
 152
 153                         /* wait a minute before checking again. */
 154                         sleep(60 * 1000);
 155                 }
 156         }
 157
 158         private void detectChangesInIdentities(Collection<OwnIdentity> currentOwnIdentities, Multimap<OwnIdentity, Identity> newIdentities, Multimap<OwnIdentity, Identity> oldIdentities) {
 159                 IdentityChangeDetector identityChangeDetector = new IdentityChangeDetector(getAllOwnIdentities());
 160                 identityChangeDetector.onNewIdentity(addNewOwnIdentityAndItsTrustedIdentities(newIdentities));
 161                 identityChangeDetector.onRemovedIdentity(removeOwnIdentityAndItsTrustedIdentities(oldIdentities));
 162                 identityChangeDetector.onUnchangedIdentity(detectChangesInTrustedIdentities(newIdentities, oldIdentities));
 163                 identityChangeDetector.detectChanges(currentOwnIdentities);
 164         }
 165
 166         private IdentityProcessor detectChangesInTrustedIdentities(Multimap<OwnIdentity, Identity> newIdentities, Multimap<OwnIdentity, Identity> oldIdentities) {
 167                 return new DefaultIdentityProcessor(oldIdentities, newIdentities);
 168         }
 169
 170         private IdentityProcessor removeOwnIdentityAndItsTrustedIdentities(final Multimap<OwnIdentity, Identity> oldIdentities) {
 171                 return new IdentityProcessor() {
 172                         @Override
 173                         public void processIdentity(Identity identity) {
 174                                 eventBus.post(new OwnIdentityRemovedEvent((OwnIdentity) identity));
 175                                 for (Identity removedIdentity : oldIdentities.get((OwnIdentity) identity)) {
 176                                         eventBus.post(new IdentityRemovedEvent((OwnIdentity) identity, removedIdentity));
 177                                 }
 178                         }
 179                 };
 180         }
 181
 182         private IdentityProcessor addNewOwnIdentityAndItsTrustedIdentities(final Multimap<OwnIdentity, Identity> newIdentities) {
 183                 return new IdentityProcessor() {
 184                         @Override
 185                         public void processIdentity(Identity identity) {
 186                                 eventBus.post(new OwnIdentityAddedEvent((OwnIdentity) identity));
 187                                 for (Identity newIdentity : newIdentities.get((OwnIdentity) identity)) {
 188                                         eventBus.post(new IdentityAddedEvent((OwnIdentity) identity, newIdentity));
 189                                 }
 190                         }
 191                 };
 192         }
 193
 194         private Multimap<OwnIdentity, Identity> loadTrustedIdentitiesForOwnIdentities(Collection<OwnIdentity> ownIdentities) throws PluginException {
 195                 Multimap<OwnIdentity, Identity> currentIdentities = create();
 196
 197                 for (OwnIdentity ownIdentity : ownIdentities) {
 198                         if ((context != null) && !ownIdentity.hasContext(context)) {
 199                                 continue;
 200                         }
 201
 202                         logger.finer(String.format("Getting trusted identities for %s...", ownIdentity.getId()));
 203                         Set<Identity> trustedIdentities = webOfTrustConnector.loadTrustedIdentities(ownIdentity, context);
 204                         logger.finest(String.format("Got %d trusted identities.", trustedIdentities.size()));
 205                         currentIdentities.putAll(ownIdentity, trustedIdentities);
 206                 }
 207
 208                 return currentIdentities;
 209         }
 210
 211         private class DefaultIdentityProcessor implements IdentityProcessor {
 212
 213                 private final Multimap<OwnIdentity, Identity> oldIdentities;
 214                 private final Multimap<OwnIdentity, Identity> newIdentities;
 215
 216                 public DefaultIdentityProcessor(Multimap<OwnIdentity, Identity> oldIdentities, Multimap<OwnIdentity, Identity> newIdentities) {
 217                         this.oldIdentities = oldIdentities;
 218                         this.newIdentities = newIdentities;
 219                 }
 220
 221                 @Override
 222                 public void processIdentity(Identity ownIdentity) {
 223                         IdentityChangeDetector identityChangeDetector = new IdentityChangeDetector(oldIdentities.get((OwnIdentity) ownIdentity));
 224                         identityChangeDetector.onNewIdentity(notifyForAddedIdentities((OwnIdentity) ownIdentity));
 225                         identityChangeDetector.onRemovedIdentity(notifyForRemovedIdentities((OwnIdentity) ownIdentity));
 226                         identityChangeDetector.onChangedIdentity(notifyForChangedIdentities((OwnIdentity) ownIdentity));
 227                         identityChangeDetector.detectChanges(newIdentities.get((OwnIdentity) ownIdentity));
 228                 }
 229
 230                 private IdentityProcessor notifyForChangedIdentities(final OwnIdentity ownIdentity) {
 231                         return new IdentityProcessor() {
 232                                 @Override
 233                                 public void processIdentity(Identity identity) {
 234                                         eventBus.post(new IdentityUpdatedEvent(ownIdentity, identity));
 235                                 }
 236                         };
 237                 }
 238
 239                 private IdentityProcessor notifyForRemovedIdentities(final OwnIdentity ownIdentity) {
 240                         return new IdentityProcessor() {
 241                                 @Override
 242                                 public void processIdentity(Identity identity) {
 243                                         eventBus.post(new IdentityRemovedEvent(ownIdentity, identity));
 244                                 }
 245                         };
 246                 }
 247
 248                 private IdentityProcessor notifyForAddedIdentities(final OwnIdentity ownIdentity) {
 249                         return new IdentityProcessor() {
 250                                 @Override
 251                                 public void processIdentity(Identity identity) {
 252                                         eventBus.post(new IdentityAddedEvent(ownIdentity, identity));
 253                                 }
 254                         };
 255                 }
 256
 257         }
 258
 259 }