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.base.Optional.fromNullable;
  21 import static com.google.common.collect.HashMultimap.create;
  22
  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         /** The logger. */
  58         private static final Logger logger = Logging.getLogger(IdentityManager.class);
  59
  60         /** The event bus. */
  61         private final EventBus eventBus;
  62
  63         private final IdentityLoader identityLoader;
  64
  65         /** The Web of Trust connector. */
  66         private final WebOfTrustConnector webOfTrustConnector;
  67
  68         /** The currently known own identities. */
  69         /* synchronize access on syncObject. */
  70         private final Set<OwnIdentity> currentOwnIdentities = Sets.newHashSet();
  71
  72         /**
  73          * Creates a new identity manager.
  74          *
  75          * @param eventBus
  76          *              The event bus
  77          * @param webOfTrustConnector
  78          *              The Web of Trust connector
  79          * @param context
  80          *              The context to focus on (may be {@code null} to ignore contexts)
  81          */
  82         @Inject
  83         public IdentityManager(EventBus eventBus, WebOfTrustConnector webOfTrustConnector, @Named("WebOfTrustContext") String context) {
  84                 super("Sone Identity Manager", false);
  85                 this.eventBus = eventBus;
  86                 this.webOfTrustConnector = webOfTrustConnector;
  87                 this.identityLoader = new IdentityLoader(webOfTrustConnector, fromNullable(context));
  88         }
  89
  90         //
  91         // ACCESSORS
  92         //
  93
  94         /**
  95          * Returns whether the Web of Trust plugin could be reached during the last
  96          * try.
  97          *
  98          * @return {@code true} if the Web of Trust plugin is connected, {@code false}
  99          *         otherwise
 100          */
 101         public boolean isConnected() {
 102                 try {
 103                         webOfTrustConnector.ping();
 104                         return true;
 105                 } catch (PluginException pe1) {
 106                         /* not connected, ignore. */
 107                         return false;
 108                 }
 109         }
 110
 111         /**
 112          * Returns all own identities.
 113          *
 114          * @return All own identities
 115          */
 116         public Set<OwnIdentity> getAllOwnIdentities() {
 117                 synchronized (currentOwnIdentities) {
 118                         return new HashSet<OwnIdentity>(currentOwnIdentities);
 119                 }
 120         }
 121
 122         //
 123         // SERVICE METHODS
 124         //
 125
 126         @Override
 127         protected void serviceRun() {
 128                 Multimap<OwnIdentity, Identity> oldIdentities = create();
 129
 130                 while (!shouldStop()) {
 131                         try {
 132                                 Multimap<OwnIdentity, Identity> currentIdentities = identityLoader.loadIdentities();
 133
 134                                 detectChangesInIdentities(currentIdentities, oldIdentities);
 135                                 oldIdentities = currentIdentities;
 136
 137                                 synchronized (currentOwnIdentities) {
 138                                         currentOwnIdentities.clear();
 139                                         currentOwnIdentities.addAll(currentIdentities.keySet());
 140                                 }
 141                         } catch (WebOfTrustException wote1) {
 142                                 logger.log(Level.WARNING, "WoT has disappeared!", wote1);
 143                         }
 144
 145                         /* wait a minute before checking again. */
 146                         sleep(60 * 1000);
 147                 }
 148         }
 149
 150         private void detectChangesInIdentities(Multimap<OwnIdentity, Identity> newIdentities, Multimap<OwnIdentity, Identity> oldIdentities) {
 151                 IdentityChangeDetector identityChangeDetector = new IdentityChangeDetector(getAllOwnIdentities());
 152                 identityChangeDetector.onNewIdentity(addNewOwnIdentityAndItsTrustedIdentities(newIdentities));
 153                 identityChangeDetector.onRemovedIdentity(removeOwnIdentityAndItsTrustedIdentities(oldIdentities));
 154                 identityChangeDetector.onUnchangedIdentity(detectChangesInTrustedIdentities(newIdentities, oldIdentities));
 155                 identityChangeDetector.detectChanges(newIdentities.keySet());
 156         }
 157
 158         private IdentityProcessor detectChangesInTrustedIdentities(Multimap<OwnIdentity, Identity> newIdentities, Multimap<OwnIdentity, Identity> oldIdentities) {
 159                 return new DefaultIdentityProcessor(oldIdentities, newIdentities);
 160         }
 161
 162         private IdentityProcessor removeOwnIdentityAndItsTrustedIdentities(final Multimap<OwnIdentity, Identity> oldIdentities) {
 163                 return new IdentityProcessor() {
 164                         @Override
 165                         public void processIdentity(Identity identity) {
 166                                 eventBus.post(new OwnIdentityRemovedEvent((OwnIdentity) identity));
 167                                 for (Identity removedIdentity : oldIdentities.get((OwnIdentity) identity)) {
 168                                         eventBus.post(new IdentityRemovedEvent((OwnIdentity) identity, removedIdentity));
 169                                 }
 170                         }
 171                 };
 172         }
 173
 174         private IdentityProcessor addNewOwnIdentityAndItsTrustedIdentities(final Multimap<OwnIdentity, Identity> newIdentities) {
 175                 return new IdentityProcessor() {
 176                         @Override
 177                         public void processIdentity(Identity identity) {
 178                                 eventBus.post(new OwnIdentityAddedEvent((OwnIdentity) identity));
 179                                 for (Identity newIdentity : newIdentities.get((OwnIdentity) identity)) {
 180                                         eventBus.post(new IdentityAddedEvent((OwnIdentity) identity, newIdentity));
 181                                 }
 182                         }
 183                 };
 184         }
 185
 186         private class DefaultIdentityProcessor implements IdentityProcessor {
 187
 188                 private final Multimap<OwnIdentity, Identity> oldIdentities;
 189                 private final Multimap<OwnIdentity, Identity> newIdentities;
 190
 191                 public DefaultIdentityProcessor(Multimap<OwnIdentity, Identity> oldIdentities, Multimap<OwnIdentity, Identity> newIdentities) {
 192                         this.oldIdentities = oldIdentities;
 193                         this.newIdentities = newIdentities;
 194                 }
 195
 196                 @Override
 197                 public void processIdentity(Identity ownIdentity) {
 198                         IdentityChangeDetector identityChangeDetector = new IdentityChangeDetector(oldIdentities.get((OwnIdentity) ownIdentity));
 199                         identityChangeDetector.onNewIdentity(notifyForAddedIdentities((OwnIdentity) ownIdentity));
 200                         identityChangeDetector.onRemovedIdentity(notifyForRemovedIdentities((OwnIdentity) ownIdentity));
 201                         identityChangeDetector.onChangedIdentity(notifyForChangedIdentities((OwnIdentity) ownIdentity));
 202                         identityChangeDetector.detectChanges(newIdentities.get((OwnIdentity) ownIdentity));
 203                 }
 204
 205                 private IdentityProcessor notifyForChangedIdentities(final OwnIdentity ownIdentity) {
 206                         return new IdentityProcessor() {
 207                                 @Override
 208                                 public void processIdentity(Identity identity) {
 209                                         eventBus.post(new IdentityUpdatedEvent(ownIdentity, identity));
 210                                 }
 211                         };
 212                 }
 213
 214                 private IdentityProcessor notifyForRemovedIdentities(final OwnIdentity ownIdentity) {
 215                         return new IdentityProcessor() {
 216                                 @Override
 217                                 public void processIdentity(Identity identity) {
 218                                         eventBus.post(new IdentityRemovedEvent(ownIdentity, identity));
 219                                 }
 220                         };
 221                 }
 222
 223                 private IdentityProcessor notifyForAddedIdentities(final OwnIdentity ownIdentity) {
 224                         return new IdentityProcessor() {
 225                                 @Override
 226                                 public void processIdentity(Identity identity) {
 227                                         eventBus.post(new IdentityAddedEvent(ownIdentity, identity));
 228                                 }
 229                         };
 230                 }
 231
 232         }
 233
 234 }