src/main/java/net/pterodactylus/sone/core/SoneInserter.java

   1 /*
   2  * Sone - SoneInserter.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.core;
  19
  20 import static java.lang.String.format;
  21 import static java.lang.System.currentTimeMillis;
  22 import static java.util.logging.Logger.getLogger;
  23 import static net.pterodactylus.sone.data.Album.NOT_EMPTY;
  24
  25 import java.io.InputStream;
  26 import java.io.InputStreamReader;
  27 import java.io.StringWriter;
  28 import java.nio.charset.Charset;
  29 import java.util.HashMap;
  30 import java.util.HashSet;
  31 import java.util.Map;
  32 import java.util.concurrent.atomic.AtomicInteger;
  33 import java.util.logging.Level;
  34 import java.util.logging.Logger;
  35
  36 import net.pterodactylus.sone.core.SoneModificationDetector.LockableFingerprintProvider;
  37 import net.pterodactylus.sone.core.event.InsertionDelayChangedEvent;
  38 import net.pterodactylus.sone.core.event.SoneInsertAbortedEvent;
  39 import net.pterodactylus.sone.core.event.SoneInsertedEvent;
  40 import net.pterodactylus.sone.core.event.SoneInsertingEvent;
  41 import net.pterodactylus.sone.data.Album;
  42 import net.pterodactylus.sone.data.LocalSone;
  43 import net.pterodactylus.sone.data.Post;
  44 import net.pterodactylus.sone.data.Reply;
  45 import net.pterodactylus.sone.data.Sone;
  46 import net.pterodactylus.sone.data.Sone.SoneStatus;
  47 import net.pterodactylus.sone.database.Database;
  48 import net.pterodactylus.sone.freenet.StringBucket;
  49 import net.pterodactylus.sone.main.SonePlugin;
  50 import net.pterodactylus.util.io.Closer;
  51 import net.pterodactylus.util.service.AbstractService;
  52 import net.pterodactylus.util.template.HtmlFilter;
  53 import net.pterodactylus.util.template.ReflectionAccessor;
  54 import net.pterodactylus.util.template.Template;
  55 import net.pterodactylus.util.template.TemplateContext;
  56 import net.pterodactylus.util.template.TemplateContextFactory;
  57 import net.pterodactylus.util.template.TemplateException;
  58 import net.pterodactylus.util.template.TemplateParser;
  59 import net.pterodactylus.util.template.XmlFilter;
  60
  61 import com.google.common.annotations.VisibleForTesting;
  62 import com.google.common.base.Optional;
  63 import com.google.common.collect.FluentIterable;
  64 import com.google.common.collect.Ordering;
  65 import com.google.common.eventbus.EventBus;
  66 import com.google.common.eventbus.Subscribe;
  67
  68 import freenet.client.async.ManifestElement;
  69 import freenet.keys.FreenetURI;
  70
  71 /**
  72  * A Sone inserter is responsible for inserting a Sone if it has changed.
  73  *
  74  * @author <a href="mailto:bombe@pterodactylus.net">David ‘Bombe’ Roden</a>
  75  */
  76 public class SoneInserter extends AbstractService {
  77
  78         /** The logger. */
  79         private static final Logger logger = getLogger("Sone.Inserter");
  80
  81         /** The insertion delay (in seconds). */
  82         private static final AtomicInteger insertionDelay = new AtomicInteger(60);
  83
  84         /** The template factory used to create the templates. */
  85         private static final TemplateContextFactory templateContextFactory = new TemplateContextFactory();
  86
  87         static {
  88                 templateContextFactory.addAccessor(Object.class, new ReflectionAccessor());
  89                 templateContextFactory.addFilter("xml", new XmlFilter());
  90                 templateContextFactory.addFilter("html", new HtmlFilter());
  91         }
  92
  93         /** The UTF-8 charset. */
  94         private static final Charset utf8Charset = Charset.forName("UTF-8");
  95
  96         /** The core. */
  97         private final Core core;
  98
  99         /** The event bus. */
 100         private final EventBus eventBus;
 101
 102         /** The Freenet interface. */
 103         private final FreenetInterface freenetInterface;
 104         private final Database database;
 105         private final SoneModificationDetector soneModificationDetector;
 106         private final long delay;
 107         private final String soneId;
 108
 109         /**
 110          * Creates a new Sone inserter.
 111          *
 112          * @param core
 113          *            The core
 114          * @param eventBus
 115          *            The event bus
 116          * @param freenetInterface
 117          *            The freenet interface
 118          * @param soneId
 119          *            The ID of the Sone to insert
 120          */
 121         public SoneInserter(final Core core, EventBus eventBus, FreenetInterface freenetInterface, Database database, final String soneId) {
 122                 this(core, eventBus, freenetInterface, database, soneId, new SoneModificationDetector(new LockableFingerprintProvider() {
 123                         @Override
 124                         public boolean isLocked() {
 125                                 final Optional<LocalSone> sone = core.getLocalSone(soneId);
 126                                 if (!sone.isPresent()) {
 127                                         return false;
 128                                 }
 129                                 return core.isLocked(sone.get());
 130                         }
 131
 132                         @Override
 133                         public String getFingerprint() {
 134                                 final Optional<Sone> sone = core.getSone(soneId);
 135                                 if (!sone.isPresent()) {
 136                                         return null;
 137                                 }
 138                                 return sone.get().getFingerprint();
 139                         }
 140                 }, insertionDelay), 1000);
 141         }
 142
 143         @VisibleForTesting
 144         SoneInserter(Core core, EventBus eventBus, FreenetInterface freenetInterface, Database database, String soneId, SoneModificationDetector soneModificationDetector, long delay) {
 145                 super("Sone Inserter for “" + soneId + "”", false);
 146                 this.core = core;
 147                 this.eventBus = eventBus;
 148                 this.freenetInterface = freenetInterface;
 149                 this.database = database;
 150                 this.soneId = soneId;
 151                 this.soneModificationDetector = soneModificationDetector;
 152                 this.delay = delay;
 153         }
 154
 155         //
 156         // ACCESSORS
 157         //
 158
 159         @VisibleForTesting
 160         static AtomicInteger getInsertionDelay() {
 161                 return insertionDelay;
 162         }
 163
 164         /**
 165          * Changes the insertion delay, i.e. the time the Sone inserter waits after it
 166          * has noticed a Sone modification before it starts the insert.
 167          *
 168          * @param insertionDelay
 169          *            The insertion delay (in seconds)
 170          */
 171         private static void setInsertionDelay(int insertionDelay) {
 172                 SoneInserter.insertionDelay.set(insertionDelay);
 173         }
 174
 175         /**
 176          * Returns the fingerprint of the last insert.
 177          *
 178          * @return The fingerprint of the last insert
 179          */
 180         public String getLastInsertFingerprint() {
 181                 return soneModificationDetector.getOriginalFingerprint();
 182         }
 183
 184         /**
 185          * Sets the fingerprint of the last insert.
 186          *
 187          * @param lastInsertFingerprint
 188          *            The fingerprint of the last insert
 189          */
 190         public void setLastInsertFingerprint(String lastInsertFingerprint) {
 191                 soneModificationDetector.setFingerprint(lastInsertFingerprint);
 192         }
 193
 194         /**
 195          * Returns whether the Sone inserter has detected a modification of the
 196          * Sone.
 197          *
 198          * @return {@code true} if the Sone has been modified, {@code false}
 199          *         otherwise
 200          */
 201         public boolean isModified() {
 202                 return soneModificationDetector.isModified();
 203         }
 204
 205         //
 206         // SERVICE METHODS
 207         //
 208
 209         /**
 210          * {@inheritDoc}
 211          */
 212         @Override
 213         protected void serviceRun() {
 214                 while (!shouldStop()) {
 215                         try {
 216                                 /* check every second. */
 217                                 sleep(delay);
 218
 219                                 if (soneModificationDetector.isEligibleForInsert()) {
 220                                         Optional<LocalSone> soneOptional = core.getLocalSone(soneId);
 221                                         if (!soneOptional.isPresent()) {
 222                                                 logger.log(Level.WARNING, format("Sone %s has disappeared, exiting inserter.", soneId));
 223                                                 return;
 224                                         }
 225                                         LocalSone sone = soneOptional.get();
 226                                         InsertInformation insertInformation = new InsertInformation(sone);
 227                                         logger.log(Level.INFO, String.format("Inserting Sone “%s”…", sone.getName()));
 228
 229                                         boolean success = false;
 230                                         try {
 231                                                 sone.setStatus(SoneStatus.inserting);
 232                                                 long insertTime = currentTimeMillis();
 233                                                 eventBus.post(new SoneInsertingEvent(sone));
 234                                                 FreenetURI finalUri = freenetInterface.insertDirectory(sone.getInsertUri(), insertInformation.generateManifestEntries(), "index.html");
 235                                                 eventBus.post(new SoneInsertedEvent(sone, currentTimeMillis() - insertTime, insertInformation.getFingerprint()));
 236                                                 /* at this point we might already be stopped. */
 237                                                 if (shouldStop()) {
 238                                                         /* if so, bail out, don’t change anything. */
 239                                                         break;
 240                                                 }
 241                                                 database.updateSoneTime(sone, insertTime);
 242                                                 sone.setLatestEdition(finalUri.getEdition());
 243                                                 core.touchConfiguration();
 244                                                 success = true;
 245                                                 logger.log(Level.INFO, String.format("Inserted Sone “%s” at %s.", sone.getName(), finalUri));
 246                                         } catch (SoneException se1) {
 247                                                 eventBus.post(new SoneInsertAbortedEvent(sone, se1));
 248                                                 logger.log(Level.WARNING, String.format("Could not insert Sone “%s”!", sone.getName()), se1);
 249                                         } finally {
 250                                                 sone.setStatus(SoneStatus.idle);
 251                                         }
 252
 253                                         /*
 254                                          * reset modification counter if Sone has not been modified
 255                                          * while it was inserted.
 256                                          */
 257                                         if (success) {
 258                                                 synchronized (sone) {
 259                                                         if (insertInformation.getFingerprint().equals(sone.getFingerprint())) {
 260                                                                 logger.log(Level.FINE, String.format("Sone “%s” was not modified further, resetting counter…", sone));
 261                                                                 soneModificationDetector.setFingerprint(insertInformation.getFingerprint());
 262                                                                 core.touchConfiguration();
 263                                                         }
 264                                                 }
 265                                         }
 266                                 }
 267                         } catch (Throwable t1) {
 268                                 logger.log(Level.SEVERE, "SoneInserter threw an Exception!", t1);
 269                         }
 270                 }
 271         }
 272
 273         @Subscribe
 274         public void insertionDelayChanged(InsertionDelayChangedEvent insertionDelayChangedEvent) {
 275                 setInsertionDelay(insertionDelayChangedEvent.getInsertionDelay());
 276         }
 277
 278         /**
 279          * Container for information that are required to insert a Sone. This
 280          * container merely exists to copy all relevant data without holding a lock
 281          * on the {@link Sone} object for too long.
 282          *
 283          * @author <a href="mailto:bombe@pterodactylus.net">David ‘Bombe’ Roden</a>
 284          */
 285         @VisibleForTesting
 286         class InsertInformation {
 287
 288                 private final String fingerprint;
 289                 private final ManifestCreator manifestCreator;
 290
 291                 /**
 292                  * Creates a new insert information container.
 293                  *
 294                  * @param sone
 295                  *            The sone to insert
 296                  */
 297                 public InsertInformation(Sone sone) {
 298                         this.fingerprint = sone.getFingerprint();
 299                         Map<String, Object> soneProperties = new HashMap<String, Object>();
 300                         soneProperties.put("id", sone.getId());
 301                         soneProperties.put("name", sone.getName());
 302                         soneProperties.put("time", currentTimeMillis());
 303                         soneProperties.put("requestUri", sone.getRequestUri());
 304                         soneProperties.put("profile", sone.getProfile());
 305                         soneProperties.put("posts", Ordering.from(Post.TIME_COMPARATOR).sortedCopy(sone.getPosts()));
 306                         soneProperties.put("replies", Ordering.from(Reply.TIME_COMPARATOR).reverse().sortedCopy(sone.getReplies()));
 307                         soneProperties.put("likedPostIds", new HashSet<String>(sone.getLikedPostIds()));
 308                         soneProperties.put("likedReplyIds", new HashSet<String>(sone.getLikedReplyIds()));
 309                         soneProperties.put("albums", FluentIterable.from(sone.getRootAlbum().getAlbums()).transformAndConcat(Album.FLATTENER).filter(NOT_EMPTY).toList());
 310                         manifestCreator = new ManifestCreator(core, soneProperties);
 311                 }
 312
 313                 //
 314                 // ACCESSORS
 315                 //
 316
 317                 @VisibleForTesting
 318                 String getFingerprint() {
 319                         return fingerprint;
 320                 }
 321
 322                 //
 323                 // ACTIONS
 324                 //
 325
 326                 /**
 327                  * Generates all manifest entries required to insert this Sone.
 328                  *
 329                  * @return The manifest entries for the Sone insert
 330                  */
 331                 public HashMap<String, Object> generateManifestEntries() {
 332                         HashMap<String, Object> manifestEntries = new HashMap<String, Object>();
 333
 334                         /* first, create an index.html. */
 335                         manifestEntries.put("index.html", manifestCreator.createManifestElement(
 336                                         "index.html", "text/html; charset=utf-8",
 337                                         "/templates/insert/index.html"));
 338
 339                         /* now, store the sone. */
 340                         manifestEntries.put("sone.xml", manifestCreator.createManifestElement(
 341                                         "sone.xml", "text/xml; charset=utf-8",
 342                                         "/templates/insert/sone.xml"));
 343
 344                         return manifestEntries;
 345                 }
 346
 347         }
 348
 349         /**
 350          * Creates manifest elements for an insert by rendering a template.
 351          *
 352          * @author <a href="mailto:bombe@pterodactylus.net">David ‘Bombe’ Roden</a>
 353          */
 354         @VisibleForTesting
 355         static class ManifestCreator {
 356
 357                 private final Core core;
 358                 private final Map<String, Object> soneProperties;
 359
 360                 ManifestCreator(Core core, Map<String, Object> soneProperties) {
 361                         this.core = core;
 362                         this.soneProperties = soneProperties;
 363                 }
 364
 365                 public ManifestElement createManifestElement(String name, String contentType, String templateName) {
 366                         InputStreamReader templateInputStreamReader = null;
 367                         InputStream templateInputStream = null;
 368                         Template template;
 369                         try {
 370                                 templateInputStream = getClass().getResourceAsStream(templateName);
 371                                 templateInputStreamReader = new InputStreamReader(templateInputStream, utf8Charset);
 372                                 template = TemplateParser.parse(templateInputStreamReader);
 373                         } catch (TemplateException te1) {
 374                                 logger.log(Level.SEVERE, String.format("Could not parse template “%s”!", templateName), te1);
 375                                 return null;
 376                         } finally {
 377                                 Closer.close(templateInputStreamReader);
 378                                 Closer.close(templateInputStream);
 379                         }
 380
 381                         TemplateContext templateContext = templateContextFactory.createTemplateContext();
 382                         templateContext.set("core", core);
 383                         templateContext.set("currentSone", soneProperties);
 384                         templateContext.set("currentEdition", core.getUpdateChecker().getLatestEdition());
 385                         templateContext.set("version", SonePlugin.VERSION);
 386                         StringWriter writer = new StringWriter();
 387                         StringBucket bucket = null;
 388                         try {
 389                                 template.render(templateContext, writer);
 390                                 bucket = new StringBucket(writer.toString(), utf8Charset);
 391                                 return new ManifestElement(name, bucket, contentType, bucket.size());
 392                         } catch (TemplateException te1) {
 393                                 logger.log(Level.SEVERE, String.format("Could not render template “%s”!", templateName), te1);
 394                                 return null;
 395                         } finally {
 396                                 Closer.close(writer);
 397                                 if (bucket != null) {
 398                                         bucket.free();
 399                                 }
 400                         }
 401                 }
 402
 403         }
 404
 405 }