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