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.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.eventbus.EventBus;
  39 import com.google.inject.Inject;
  40 import com.google.inject.name.Named;
  41
  42 /**
  43  * The identity manager takes care of loading and storing identities, their
  44  * contexts, and properties. It does so in a way that does not expose errors via
  45  * exceptions but it only logs them and tries to return sensible defaults.
  46  * <p>
  47  * It is also responsible for polling identities from the Web of Trust plugin
  48  * and sending events to the {@link EventBus} when {@link Identity}s and
  49  * {@link OwnIdentity}s are discovered or disappearing.
  50  *
  51  * @author <a href="mailto:bombe@pterodactylus.net">David ‘Bombe’ Roden</a>
  52  */
  53 public class IdentityManager extends AbstractService {
  54
  55         /** Object used for synchronization. */
  56         @SuppressWarnings("hiding")
  57         private final Object syncObject = new Object() {
  58                 /* inner class for better lock names. */
  59         };
  60
  61         /** The logger. */
  62         private static final Logger logger = Logging.getLogger(IdentityManager.class);
  63
  64         /** The event bus. */
  65         private final EventBus eventBus;
  66
  67         /** The Web of Trust connector. */
  68         private final WebOfTrustConnector webOfTrustConnector;
  69
  70         /** The context to filter for. */
  71         private final String context;
  72
  73         /** The currently known own identities. */
  74         /* synchronize access on syncObject. */
  75         private final Map<String, OwnIdentity> currentOwnIdentities = new HashMap<String, OwnIdentity>();
  76
  77         /** The last time all identities were loaded. */
  78         private volatile long identitiesLastLoaded;
  79
  80         /**
  81          * Creates a new identity manager.
  82          *
  83          * @param eventBus
  84          *            The event bus
  85          * @param webOfTrustConnector
  86          *            The Web of Trust connector
  87          * @param context
  88          *            The context to focus on (may be {@code null} to ignore
  89          *            contexts)
  90          */
  91         @Inject
  92         public IdentityManager(EventBus eventBus, WebOfTrustConnector webOfTrustConnector, @Named("WebOfTrustContext") String context) {
  93                 super("Sone Identity Manager", false);
  94                 this.eventBus = eventBus;
  95                 this.webOfTrustConnector = webOfTrustConnector;
  96                 this.context = context;
  97         }
  98
  99         //
 100         // ACCESSORS
 101         //
 102
 103         /**
 104          * Returns the last time all identities were loaded.
 105          *
 106          * @return The last time all identities were loaded (in milliseconds since
 107          *         Jan 1, 1970 UTC)
 108          */
 109         public long getIdentitiesLastLoaded() {
 110                 return identitiesLastLoaded;
 111         }
 112
 113         /**
 114          * Returns whether the Web of Trust plugin could be reached during the last
 115          * try.
 116          *
 117          * @return {@code true} if the Web of Trust plugin is connected,
 118          *         {@code false} otherwise
 119          */
 120         public boolean isConnected() {
 121                 try {
 122                         webOfTrustConnector.ping();
 123                         return true;
 124                 } catch (PluginException pe1) {
 125                         /* not connected, ignore. */
 126                         return false;
 127                 }
 128         }
 129
 130         /**
 131          * Returns the own identity with the given ID.
 132          *
 133          * @param id
 134          *            The ID of the own identity
 135          * @return The own identity, or {@code null} if there is no such identity
 136          */
 137         public OwnIdentity getOwnIdentity(String id) {
 138                 Set<OwnIdentity> allOwnIdentities = getAllOwnIdentities();
 139                 for (OwnIdentity ownIdentity : allOwnIdentities) {
 140                         if (ownIdentity.getId().equals(id)) {
 141                                 return new DefaultOwnIdentity(ownIdentity);
 142                         }
 143                 }
 144                 return null;
 145         }
 146
 147         /**
 148          * Returns all own identities.
 149          *
 150          * @return All own identities
 151          */
 152         public Set<OwnIdentity> getAllOwnIdentities() {
 153                 return new HashSet<OwnIdentity>(currentOwnIdentities.values());
 154         }
 155
 156         //
 157         // SERVICE METHODS
 158         //
 159
 160         /**
 161          * {@inheritDoc}
 162          */
 163         @Override
 164         protected void serviceRun() {
 165                 Map<OwnIdentity, Map<String, Identity>> oldIdentities = Collections.emptyMap();
 166                 while (!shouldStop()) {
 167                         Map<OwnIdentity, Map<String, Identity>> currentIdentities = new HashMap<OwnIdentity, Map<String, Identity>>();
 168                         Map<String, OwnIdentity> currentOwnIdentities = new HashMap<String, OwnIdentity>();
 169
 170                         Set<OwnIdentity> ownIdentities = null;
 171                         boolean identitiesLoaded = false;
 172                         try {
 173                                 /* get all identities with the wanted context from WoT. */
 174                                 ownIdentities = webOfTrustConnector.loadAllOwnIdentities();
 175
 176                                 /* load trusted identities. */
 177                                 for (OwnIdentity ownIdentity : ownIdentities) {
 178                                         currentOwnIdentities.put(ownIdentity.getId(), ownIdentity);
 179                                         Map<String, Identity> identities = new HashMap<String, Identity>();
 180                                         currentIdentities.put(ownIdentity, identities);
 181
 182                                         /*
 183                                          * if the context doesn’t match, skip getting trusted
 184                                          * identities.
 185                                          */
 186                                         if ((context != null) && !ownIdentity.hasContext(context)) {
 187                                                 continue;
 188                                         }
 189
 190                                         /* load trusted identities. */
 191                                         Set<Identity> trustedIdentities = webOfTrustConnector.loadTrustedIdentities(ownIdentity, context);
 192                                         for (Identity identity : trustedIdentities) {
 193                                                 identities.put(identity.getId(), identity);
 194                                         }
 195                                 }
 196                                 identitiesLoaded = true;
 197                                 identitiesLastLoaded = System.currentTimeMillis();
 198                         } catch (WebOfTrustException wote1) {
 199                                 logger.log(Level.WARNING, "WoT has disappeared!", wote1);
 200                         }
 201
 202                         if (identitiesLoaded) {
 203
 204                                 /* check for changes. */
 205                                 checkOwnIdentities(currentOwnIdentities);
 206
 207                                 /* now check for changes in remote identities. */
 208                                 for (OwnIdentity ownIdentity : currentOwnIdentities.values()) {
 209
 210                                         /* find new identities. */
 211                                         for (Identity currentIdentity : currentIdentities.get(ownIdentity).values()) {
 212                                                 if (!oldIdentities.containsKey(ownIdentity) || !oldIdentities.get(ownIdentity).containsKey(currentIdentity.getId())) {
 213                                                         eventBus.post(new IdentityAddedEvent(ownIdentity, currentIdentity));
 214                                                 }
 215                                         }
 216
 217                                         /* find removed identities. */
 218                                         if (oldIdentities.containsKey(ownIdentity)) {
 219                                                 for (Identity oldIdentity : oldIdentities.get(ownIdentity).values()) {
 220                                                         if (!currentIdentities.get(ownIdentity).containsKey(oldIdentity.getId())) {
 221                                                                 eventBus.post(new IdentityRemovedEvent(ownIdentity, oldIdentity));
 222                                                         }
 223                                                 }
 224
 225                                                 /* check for changes in the contexts. */
 226                                                 for (Identity oldIdentity : oldIdentities.get(ownIdentity).values()) {
 227                                                         if (!currentIdentities.get(ownIdentity).containsKey(oldIdentity.getId())) {
 228                                                                 continue;
 229                                                         }
 230                                                         Identity newIdentity = currentIdentities.get(ownIdentity).get(oldIdentity.getId());
 231                                                         Set<String> oldContexts = oldIdentity.getContexts();
 232                                                         Set<String> newContexts = newIdentity.getContexts();
 233                                                         if (oldContexts.size() != newContexts.size()) {
 234                                                                 eventBus.post(new IdentityUpdatedEvent(ownIdentity, newIdentity));
 235                                                                 continue;
 236                                                         }
 237                                                         for (String oldContext : oldContexts) {
 238                                                                 if (!newContexts.contains(oldContext)) {
 239                                                                         eventBus.post(new IdentityUpdatedEvent(ownIdentity, newIdentity));
 240                                                                         break;
 241                                                                 }
 242                                                         }
 243                                                 }
 244
 245                                                 /* check for changes in the properties. */
 246                                                 for (Identity oldIdentity : oldIdentities.get(ownIdentity).values()) {
 247                                                         if (!currentIdentities.get(ownIdentity).containsKey(oldIdentity.getId())) {
 248                                                                 continue;
 249                                                         }
 250                                                         Identity newIdentity = currentIdentities.get(ownIdentity).get(oldIdentity.getId());
 251                                                         Map<String, String> oldProperties = oldIdentity.getProperties();
 252                                                         Map<String, String> newProperties = newIdentity.getProperties();
 253                                                         if (oldProperties.size() != newProperties.size()) {
 254                                                                 eventBus.post(new IdentityUpdatedEvent(ownIdentity, newIdentity));
 255                                                                 continue;
 256                                                         }
 257                                                         for (Entry<String, String> oldProperty : oldProperties.entrySet()) {
 258                                                                 if (!newProperties.containsKey(oldProperty.getKey()) || !newProperties.get(oldProperty.getKey()).equals(oldProperty.getValue())) {
 259                                                                         eventBus.post(new IdentityUpdatedEvent(ownIdentity, newIdentity));
 260                                                                         break;
 261                                                                 }
 262                                                         }
 263                                                 }
 264                                         }
 265                                 }
 266
 267                                 /* remember the current set of identities. */
 268                                 oldIdentities = currentIdentities;
 269                         }
 270
 271                         /* wait a minute before checking again. */
 272                         sleep(60 * 1000);
 273                 }
 274         }
 275
 276         //
 277         // PRIVATE METHODS
 278         //
 279
 280         /**
 281          * Checks the given new list of own identities for added or removed own
 282          * identities, as compared to {@link #currentOwnIdentities}.
 283          *
 284          * @param newOwnIdentities
 285          *            The new own identities
 286          */
 287         private void checkOwnIdentities(Map<String, OwnIdentity> newOwnIdentities) {
 288                 synchronized (syncObject) {
 289
 290                         /* find removed own identities: */
 291                         for (OwnIdentity oldOwnIdentity : currentOwnIdentities.values()) {
 292                                 OwnIdentity newOwnIdentity = newOwnIdentities.get(oldOwnIdentity.getId());
 293                                 if ((newOwnIdentity == null) || ((context != null) && oldOwnIdentity.hasContext(context) && !newOwnIdentity.hasContext(context))) {
 294                                         eventBus.post(new OwnIdentityRemovedEvent(new DefaultOwnIdentity(oldOwnIdentity)));
 295                                 }
 296                         }
 297
 298                         /* find added own identities. */
 299                         for (OwnIdentity currentOwnIdentity : newOwnIdentities.values()) {
 300                                 OwnIdentity oldOwnIdentity = currentOwnIdentities.get(currentOwnIdentity.getId());
 301                                 if (((oldOwnIdentity == null) && ((context == null) || currentOwnIdentity.hasContext(context))) || ((oldOwnIdentity != null) && (context != null) && (!oldOwnIdentity.hasContext(context) && currentOwnIdentity.hasContext(context)))) {
 302                                         eventBus.post(new OwnIdentityAddedEvent(new DefaultOwnIdentity(currentOwnIdentity)));
 303                                 }
 304                         }
 305
 306                         currentOwnIdentities.clear();
 307                         currentOwnIdentities.putAll(newOwnIdentities);
 308                 }
 309         }
 310
 311 }