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 import com.google.inject.Inject;
  34 import com.google.inject.name.Named;
  35
  36 /**
  37  * The identity manager takes care of loading and storing identities, their
  38  * contexts, and properties. It does so in a way that does not expose errors via
  39  * exceptions but it only logs them and tries to return sensible defaults.
  40  * <p>
  41  * It is also responsible for polling identities from the Web of Trust plugin
  42  * and notifying registered {@link IdentityListener}s when {@link Identity}s and
  43  * {@link OwnIdentity}s are discovered or disappearing.
  44  *
  45  * @author <a href="mailto:bombe@pterodactylus.net">David ‘Bombe’ Roden</a>
  46  */
  47 public class IdentityManager extends AbstractService {
  48
  49         /** Object used for synchronization. */
  50         @SuppressWarnings("hiding")
  51         private final Object syncObject = new Object() {
  52                 /* inner class for better lock names. */
  53         };
  54
  55         /** The logger. */
  56         private static final Logger logger = Logging.getLogger(IdentityManager.class);
  57
  58         /** The event manager. */
  59         private final IdentityListenerManager identityListenerManager = new IdentityListenerManager();
  60
  61         /** The Web of Trust connector. */
  62         private final WebOfTrustConnector webOfTrustConnector;
  63
  64         /** The context to filter for. */
  65         private final String context;
  66
  67         /** The currently known own identities. */
  68         /* synchronize access on syncObject. */
  69         private final Map<String, OwnIdentity> currentOwnIdentities = new HashMap<String, OwnIdentity>();
  70
  71         /** The last time all identities were loaded. */
  72         private volatile long identitiesLastLoaded;
  73
  74         /**
  75          * Creates a new identity manager.
  76          *
  77          * @param webOfTrustConnector
  78          *            The Web of Trust connector
  79          * @param context
  80          *            The context to focus on (may be {@code null} to ignore
  81          *            contexts)
  82          */
  83         @Inject
  84         public IdentityManager(WebOfTrustConnector webOfTrustConnector, @Named("WebOfTrustContext") String context) {
  85                 super("Sone Identity Manager", false);
  86                 this.webOfTrustConnector = webOfTrustConnector;
  87                 this.context = context;
  88         }
  89
  90         //
  91         // LISTENER MANAGEMENT
  92         //
  93
  94         /**
  95          * Adds a listener for identity events.
  96          *
  97          * @param identityListener
  98          *            The listener to add
  99          */
 100         public void addIdentityListener(IdentityListener identityListener) {
 101                 identityListenerManager.addListener(identityListener);
 102         }
 103
 104         /**
 105          * Removes a listener for identity events.
 106          *
 107          * @param identityListener
 108          *            The listener to remove
 109          */
 110         public void removeIdentityListener(IdentityListener identityListener) {
 111                 identityListenerManager.removeListener(identityListener);
 112         }
 113
 114         //
 115         // ACCESSORS
 116         //
 117
 118         /**
 119          * Returns the last time all identities were loaded.
 120          *
 121          * @return The last time all identities were loaded (in milliseconds since
 122          *         Jan 1, 1970 UTC)
 123          */
 124         public long getIdentitiesLastLoaded() {
 125                 return identitiesLastLoaded;
 126         }
 127
 128         /**
 129          * Returns whether the Web of Trust plugin could be reached during the last
 130          * try.
 131          *
 132          * @return {@code true} if the Web of Trust plugin is connected,
 133          *         {@code false} otherwise
 134          */
 135         public boolean isConnected() {
 136                 try {
 137                         webOfTrustConnector.ping();
 138                         return true;
 139                 } catch (PluginException pe1) {
 140                         /* not connected, ignore. */
 141                         return false;
 142                 }
 143         }
 144
 145         /**
 146          * Returns the own identity with the given ID.
 147          *
 148          * @param id
 149          *            The ID of the own identity
 150          * @return The own identity, or {@code null} if there is no such identity
 151          */
 152         public OwnIdentity getOwnIdentity(String id) {
 153                 Set<OwnIdentity> allOwnIdentities = getAllOwnIdentities();
 154                 for (OwnIdentity ownIdentity : allOwnIdentities) {
 155                         if (ownIdentity.getId().equals(id)) {
 156                                 return new DefaultOwnIdentity(ownIdentity);
 157                         }
 158                 }
 159                 return null;
 160         }
 161
 162         /**
 163          * Returns all own identities.
 164          *
 165          * @return All own identities
 166          */
 167         public Set<OwnIdentity> getAllOwnIdentities() {
 168                 return new HashSet<OwnIdentity>(currentOwnIdentities.values());
 169         }
 170
 171         //
 172         // SERVICE METHODS
 173         //
 174
 175         /**
 176          * {@inheritDoc}
 177          */
 178         @Override
 179         protected void serviceRun() {
 180                 Map<OwnIdentity, Map<String, Identity>> oldIdentities = Collections.emptyMap();
 181                 while (!shouldStop()) {
 182                         Map<OwnIdentity, Map<String, Identity>> currentIdentities = new HashMap<OwnIdentity, Map<String, Identity>>();
 183                         Map<String, OwnIdentity> currentOwnIdentities = new HashMap<String, OwnIdentity>();
 184
 185                         Set<OwnIdentity> ownIdentities = null;
 186                         boolean identitiesLoaded = false;
 187                         try {
 188                                 /* get all identities with the wanted context from WoT. */
 189                                 ownIdentities = webOfTrustConnector.loadAllOwnIdentities();
 190
 191                                 /* load trusted identities. */
 192                                 for (OwnIdentity ownIdentity : ownIdentities) {
 193                                         currentOwnIdentities.put(ownIdentity.getId(), ownIdentity);
 194                                         Map<String, Identity> identities = new HashMap<String, Identity>();
 195                                         currentIdentities.put(ownIdentity, identities);
 196
 197                                         /* if the context doesn’t match, skip getting trusted identities. */
 198                                         if ((context != null) && !ownIdentity.hasContext(context)) {
 199                                                 continue;
 200                                         }
 201
 202                                         /* load trusted identities. */
 203                                         Set<Identity> trustedIdentities = webOfTrustConnector.loadTrustedIdentities(ownIdentity, context);
 204                                         for (Identity identity : trustedIdentities) {
 205                                                 identities.put(identity.getId(), identity);
 206                                         }
 207                                 }
 208                                 identitiesLoaded = true;
 209                                 identitiesLastLoaded = System.currentTimeMillis();
 210                         } catch (WebOfTrustException wote1) {
 211                                 logger.log(Level.WARNING, "WoT has disappeared!", wote1);
 212                         }
 213
 214                         if (identitiesLoaded) {
 215
 216                                 /* check for changes. */
 217                                 checkOwnIdentities(currentOwnIdentities);
 218
 219                                 /* now check for changes in remote identities. */
 220                                 for (OwnIdentity ownIdentity : currentOwnIdentities.values()) {
 221
 222                                         /* find new identities. */
 223                                         for (Identity currentIdentity : currentIdentities.get(ownIdentity).values()) {
 224                                                 if (!oldIdentities.containsKey(ownIdentity) || !oldIdentities.get(ownIdentity).containsKey(currentIdentity.getId())) {
 225                                                         identityListenerManager.fireIdentityAdded(ownIdentity, currentIdentity);
 226                                                 }
 227                                         }
 228
 229                                         /* find removed identities. */
 230                                         if (oldIdentities.containsKey(ownIdentity)) {
 231                                                 for (Identity oldIdentity : oldIdentities.get(ownIdentity).values()) {
 232                                                         if (!currentIdentities.get(ownIdentity).containsKey(oldIdentity.getId())) {
 233                                                                 identityListenerManager.fireIdentityRemoved(ownIdentity, oldIdentity);
 234                                                         }
 235                                                 }
 236
 237                                                 /* check for changes in the contexts. */
 238                                                 for (Identity oldIdentity : oldIdentities.get(ownIdentity).values()) {
 239                                                         if (!currentIdentities.get(ownIdentity).containsKey(oldIdentity.getId())) {
 240                                                                 continue;
 241                                                         }
 242                                                         Identity newIdentity = currentIdentities.get(ownIdentity).get(oldIdentity.getId());
 243                                                         Set<String> oldContexts = oldIdentity.getContexts();
 244                                                         Set<String> newContexts = newIdentity.getContexts();
 245                                                         if (oldContexts.size() != newContexts.size()) {
 246                                                                 identityListenerManager.fireIdentityUpdated(ownIdentity, newIdentity);
 247                                                                 continue;
 248                                                         }
 249                                                         for (String oldContext : oldContexts) {
 250                                                                 if (!newContexts.contains(oldContext)) {
 251                                                                         identityListenerManager.fireIdentityUpdated(ownIdentity, newIdentity);
 252                                                                         break;
 253                                                                 }
 254                                                         }
 255                                                 }
 256
 257                                                 /* check for changes in the properties. */
 258                                                 for (Identity oldIdentity : oldIdentities.get(ownIdentity).values()) {
 259                                                         if (!currentIdentities.get(ownIdentity).containsKey(oldIdentity.getId())) {
 260                                                                 continue;
 261                                                         }
 262                                                         Identity newIdentity = currentIdentities.get(ownIdentity).get(oldIdentity.getId());
 263                                                         Map<String, String> oldProperties = oldIdentity.getProperties();
 264                                                         Map<String, String> newProperties = newIdentity.getProperties();
 265                                                         if (oldProperties.size() != newProperties.size()) {
 266                                                                 identityListenerManager.fireIdentityUpdated(ownIdentity, newIdentity);
 267                                                                 continue;
 268                                                         }
 269                                                         for (Entry<String, String> oldProperty : oldProperties.entrySet()) {
 270                                                                 if (!newProperties.containsKey(oldProperty.getKey()) || !newProperties.get(oldProperty.getKey()).equals(oldProperty.getValue())) {
 271                                                                         identityListenerManager.fireIdentityUpdated(ownIdentity, newIdentity);
 272                                                                         break;
 273                                                                 }
 274                                                         }
 275                                                 }
 276                                         }
 277                                 }
 278
 279                                 /* remember the current set of identities. */
 280                                 oldIdentities = currentIdentities;
 281                         }
 282
 283                         /* wait a minute before checking again. */
 284                         sleep(60 * 1000);
 285                 }
 286         }
 287
 288         //
 289         // PRIVATE METHODS
 290         //
 291
 292         /**
 293          * Checks the given new list of own identities for added or removed own
 294          * identities, as compared to {@link #currentOwnIdentities}.
 295          *
 296          * @param newOwnIdentities
 297          *            The new own identities
 298          */
 299         private void checkOwnIdentities(Map<String, OwnIdentity> newOwnIdentities) {
 300                 synchronized (syncObject) {
 301
 302                         /* find removed own identities: */
 303                         for (OwnIdentity oldOwnIdentity : currentOwnIdentities.values()) {
 304                                 OwnIdentity newOwnIdentity = newOwnIdentities.get(oldOwnIdentity.getId());
 305                                 if ((newOwnIdentity == null) || ((context != null) && oldOwnIdentity.hasContext(context) && !newOwnIdentity.hasContext(context))) {
 306                                         identityListenerManager.fireOwnIdentityRemoved(new DefaultOwnIdentity(oldOwnIdentity));
 307                                 }
 308                         }
 309
 310                         /* find added own identities. */
 311                         for (OwnIdentity currentOwnIdentity : newOwnIdentities.values()) {
 312                                 OwnIdentity oldOwnIdentity = currentOwnIdentities.get(currentOwnIdentity.getId());
 313                                 if (((oldOwnIdentity == null) && ((context == null) || currentOwnIdentity.hasContext(context))) || ((oldOwnIdentity != null) && (context != null) && (!oldOwnIdentity.hasContext(context) && currentOwnIdentity.hasContext(context)))) {
 314                                         identityListenerManager.fireOwnIdentityAdded(new DefaultOwnIdentity(currentOwnIdentity));
 315                                 }
 316                         }
 317
 318                         currentOwnIdentities.clear();
 319                         currentOwnIdentities.putAll(newOwnIdentities);
 320                 }
 321         }
 322
 323 }