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 com.google.common.base.Preconditions.checkArgument;
  21 import static java.lang.String.format;
  22 import static java.lang.System.currentTimeMillis;
  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.Options.Option;
  37 import net.pterodactylus.sone.core.Options.OptionWatcher;
  38 import net.pterodactylus.sone.core.SoneModificationDetector.LockableFingerprintProvider;
  39 import net.pterodactylus.sone.core.event.SoneInsertAbortedEvent;
  40 import net.pterodactylus.sone.core.event.SoneInsertedEvent;
  41 import net.pterodactylus.sone.core.event.SoneInsertingEvent;
  42 import net.pterodactylus.sone.data.Album;
  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.freenet.StringBucket;
  48 import net.pterodactylus.sone.main.SonePlugin;
  49 import net.pterodactylus.util.io.Closer;
  50 import net.pterodactylus.util.logging.Logging;
  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
  67 import freenet.client.async.ManifestElement;
  68 import freenet.keys.FreenetURI;
  69
  70 /**
  71  * A Sone inserter is responsible for inserting a Sone if it has changed.
  72  *
  73  * @author <a href="mailto:bombe@pterodactylus.net">David ‘Bombe’ Roden</a>
  74  */
  75 public class SoneInserter extends AbstractService {
  76
  77         /** The logger. */
  78         private static final Logger logger = Logging.getLogger(SoneInserter.class);
  79
  80         /** The insertion delay (in seconds). */
  81         private static final AtomicInteger insertionDelay = new AtomicInteger(60);
  82
  83         /** The template factory used to create the templates. */
  84         private static final TemplateContextFactory templateContextFactory = new TemplateContextFactory();
  85
  86         static {
  87                 templateContextFactory.addAccessor(Object.class, new ReflectionAccessor());
  88                 templateContextFactory.addFilter("xml", new XmlFilter());
  89                 templateContextFactory.addFilter("html", new HtmlFilter());
  90         }
  91
  92         /** The UTF-8 charset. */
  93         private static final Charset utf8Charset = Charset.forName("UTF-8");
  94
  95         /** The core. */
  96         private final Core core;
  97
  98         /** The event bus. */
  99         private final EventBus eventBus;
 100
 101         /** The Freenet interface. */
 102         private final FreenetInterface freenetInterface;
 103
 104         private final SoneModificationDetector soneModificationDetector;
 105         private final long delay;
 106         private final String soneId;
 107
 108         /**
 109          * Creates a new Sone inserter.
 110          *
 111          * @param core
 112          *            The core
 113          * @param eventBus
 114          *            The event bus
 115          * @param freenetInterface
 116          *            The freenet interface
 117          * @param soneId
 118          *            The ID of the Sone to insert
 119          */
 120         public SoneInserter(final Core core, EventBus eventBus, FreenetInterface freenetInterface, final String soneId) {
 121                 this(core, eventBus, freenetInterface, soneId, new SoneModificationDetector(new LockableFingerprintProvider() {
 122                         @Override
 123                         public boolean isLocked() {
 124                                 final Optional<Sone> sone = core.getSone(soneId);
 125                                 if (!sone.isPresent()) {
 126                                         return false;
 127                                 }
 128                                 return core.isLocked(sone.get());
 129                         }
 130
 131                         @Override
 132                         public String getFingerprint() {
 133                                 final Optional<Sone> sone = core.getSone(soneId);
 134                                 if (!sone.isPresent()) {
 135                                         return null;
 136                                 }
 137                                 return sone.get().getFingerprint();
 138                         }
 139                 }, insertionDelay), 1000);
 140         }
 141
 142         @VisibleForTesting
 143         SoneInserter(Core core, EventBus eventBus, FreenetInterface freenetInterface, String soneId, SoneModificationDetector soneModificationDetector, long delay) {
 144                 super("Sone Inserter for “" + soneId + "”", false);
 145                 this.core = core;
 146                 this.eventBus = eventBus;
 147                 this.freenetInterface = freenetInterface;
 148                 this.soneId = soneId;
 149                 this.soneModificationDetector = soneModificationDetector;
 150                 this.delay = delay;
 151         }
 152
 153         //
 154         // ACCESSORS
 155         //
 156
 157         @VisibleForTesting
 158         static AtomicInteger getInsertionDelay() {
 159                 return insertionDelay;
 160         }
 161
 162         /**
 163          * Changes the insertion delay, i.e. the time the Sone inserter waits after it
 164          * has noticed a Sone modification before it starts the insert.
 165          *
 166          * @param insertionDelay
 167          *            The insertion delay (in seconds)
 168          */
 169         public static void setInsertionDelay(int insertionDelay) {
 170                 SoneInserter.insertionDelay.set(insertionDelay);
 171         }
 172
 173         /**
 174          * Returns the fingerprint of the last insert.
 175          *
 176          * @return The fingerprint of the last insert
 177          */
 178         public String getLastInsertFingerprint() {
 179                 return soneModificationDetector.getOriginalFingerprint();
 180         }
 181
 182         /**
 183          * Sets the fingerprint of the last insert.
 184          *
 185          * @param lastInsertFingerprint
 186          *            The fingerprint of the last insert
 187          */
 188         public void setLastInsertFingerprint(String lastInsertFingerprint) {
 189                 soneModificationDetector.setFingerprint(lastInsertFingerprint);
 190         }
 191
 192         /**
 193          * Returns whether the Sone inserter has detected a modification of the
 194          * Sone.
 195          *
 196          * @return {@code true} if the Sone has been modified, {@code false}
 197          *         otherwise
 198          */
 199         public boolean isModified() {
 200                 return soneModificationDetector.isModified();
 201         }
 202
 203         //
 204         // SERVICE METHODS
 205         //
 206
 207         /**
 208          * {@inheritDoc}
 209          */
 210         @Override
 211         protected void serviceRun() {
 212                 while (!shouldStop()) {
 213                         try {
 214                                 /* check every second. */
 215                                 sleep(delay);
 216
 217                                 if (soneModificationDetector.isEligibleForInsert()) {
 218                                         Optional<Sone> soneOptional = core.getSone(soneId);
 219                                         if (!soneOptional.isPresent()) {
 220                                                 logger.log(Level.WARNING, format("Sone %s has disappeared, exiting inserter.", soneId));
 221                                                 return;
 222                                         }
 223                                         Sone sone = soneOptional.get();
 224                                         InsertInformation insertInformation = new InsertInformation(sone);
 225                                         logger.log(Level.INFO, String.format("Inserting Sone “%s”…", sone.getName()));
 226
 227                                         boolean success = false;
 228                                         try {
 229                                                 sone.setStatus(SoneStatus.inserting);
 230                                                 long insertTime = currentTimeMillis();
 231                                                 eventBus.post(new SoneInsertingEvent(sone));
 232                                                 FreenetURI finalUri = freenetInterface.insertDirectory(insertInformation.getInsertUri(), insertInformation.generateManifestEntries(), "index.html");
 233                                                 eventBus.post(new SoneInsertedEvent(sone, currentTimeMillis() - insertTime));
 234                                                 /* at this point we might already be stopped. */
 235                                                 if (shouldStop()) {
 236                                                         /* if so, bail out, don’t change anything. */
 237                                                         break;
 238                                                 }
 239                                                 sone.setTime(insertTime);
 240                                                 sone.setLatestEdition(finalUri.getEdition());
 241                                                 core.touchConfiguration();
 242                                                 success = true;
 243                                                 logger.log(Level.INFO, String.format("Inserted Sone “%s” at %s.", sone.getName(), finalUri));
 244                                         } catch (SoneException se1) {
 245                                                 eventBus.post(new SoneInsertAbortedEvent(sone, se1));
 246                                                 logger.log(Level.WARNING, String.format("Could not insert Sone “%s”!", sone.getName()), se1);
 247                                         } finally {
 248                                                 sone.setStatus(SoneStatus.idle);
 249                                         }
 250
 251                                         /*
 252                                          * reset modification counter if Sone has not been modified
 253                                          * while it was inserted.
 254                                          */
 255                                         if (success) {
 256                                                 synchronized (sone) {
 257                                                         if (insertInformation.getFingerprint().equals(sone.getFingerprint())) {
 258                                                                 logger.log(Level.FINE, String.format("Sone “%s” was not modified further, resetting counter…", sone));
 259                                                                 soneModificationDetector.setFingerprint(insertInformation.getFingerprint());
 260                                                                 core.touchConfiguration();
 261                                                         }
 262                                                 }
 263                                         }
 264                                 }
 265                         } catch (Throwable t1) {
 266                                 logger.log(Level.SEVERE, "SoneInserter threw an Exception!", t1);
 267                         }
 268                 }
 269         }
 270
 271         static class SetInsertionDelay implements OptionWatcher<Integer> {
 272
 273                 @Override
 274                 public void optionChanged(Option<Integer> option, Integer oldValue, Integer newValue) {
 275                         setInsertionDelay(newValue);
 276                 }
 277
 278         }
 279
 280         /**
 281          * Container for information that are required to insert a Sone. This
 282          * container merely exists to copy all relevant data without holding a lock
 283          * on the {@link Sone} object for too long.
 284          *
 285          * @author <a href="mailto:bombe@pterodactylus.net">David ‘Bombe’ Roden</a>
 286          */
 287         @VisibleForTesting
 288         class InsertInformation {
 289
 290                 private final String fingerprint;
 291
 292                 /** All properties of the Sone, copied for thread safety. */
 293                 private final Map<String, Object> soneProperties = new HashMap<String, Object>();
 294
 295                 /**
 296                  * Creates a new insert information container.
 297                  *
 298                  * @param sone
 299                  *            The sone to insert
 300                  */
 301                 public InsertInformation(Sone sone) {
 302                         this.fingerprint = sone.getFingerprint();
 303                         soneProperties.put("id", sone.getId());
 304                         soneProperties.put("name", sone.getName());
 305                         soneProperties.put("time", currentTimeMillis());
 306                         soneProperties.put("requestUri", sone.getRequestUri());
 307                         soneProperties.put("insertUri", sone.getInsertUri());
 308                         soneProperties.put("profile", sone.getProfile());
 309                         soneProperties.put("posts", Ordering.from(Post.TIME_COMPARATOR).sortedCopy(sone.getPosts()));
 310                         soneProperties.put("replies", Ordering.from(Reply.TIME_COMPARATOR).reverse().sortedCopy(sone.getReplies()));
 311                         soneProperties.put("likedPostIds", new HashSet<String>(sone.getLikedPostIds()));
 312                         soneProperties.put("likedReplyIds", new HashSet<String>(sone.getLikedReplyIds()));
 313                         soneProperties.put("albums", FluentIterable.from(sone.getRootAlbum().getAlbums()).transformAndConcat(Album.FLATTENER).filter(NOT_EMPTY).toList());
 314                 }
 315
 316                 //
 317                 // ACCESSORS
 318                 //
 319
 320                 @VisibleForTesting
 321                 String getFingerprint() {
 322                         return fingerprint;
 323                 }
 324
 325                 /**
 326                  * Returns the insert URI of the Sone.
 327                  *
 328                  * @return The insert URI of the Sone
 329                  */
 330                 public FreenetURI getInsertUri() {
 331                         return (FreenetURI) soneProperties.get("insertUri");
 332                 }
 333
 334                 //
 335                 // ACTIONS
 336                 //
 337
 338                 /**
 339                  * Generates all manifest entries required to insert this Sone.
 340                  *
 341                  * @return The manifest entries for the Sone insert
 342                  */
 343                 public HashMap<String, Object> generateManifestEntries() {
 344                         HashMap<String, Object> manifestEntries = new HashMap<String, Object>();
 345
 346                         /* first, create an index.html. */
 347                         manifestEntries.put("index.html", createManifestElement("index.html", "text/html; charset=utf-8", "/templates/insert/index.html"));
 348
 349                         /* now, store the sone. */
 350                         manifestEntries.put("sone.xml", createManifestElement("sone.xml", "text/xml; charset=utf-8", "/templates/insert/sone.xml"));
 351
 352                         return manifestEntries;
 353                 }
 354
 355                 //
 356                 // PRIVATE METHODS
 357                 //
 358
 359                 /**
 360                  * Creates a new manifest element.
 361                  *
 362                  * @param name
 363                  *            The name of the file
 364                  * @param contentType
 365                  *            The content type of the file
 366                  * @param templateName
 367                  *            The name of the template to render
 368                  * @return The manifest element
 369                  */
 370                 @SuppressWarnings("synthetic-access")
 371                 private ManifestElement createManifestElement(String name, String contentType, String templateName) {
 372                         InputStreamReader templateInputStreamReader = null;
 373                         InputStream templateInputStream = null;
 374                         Template template;
 375                         try {
 376                                 templateInputStream = getClass().getResourceAsStream(templateName);
 377                                 templateInputStreamReader = new InputStreamReader(templateInputStream, utf8Charset);
 378                                 template = TemplateParser.parse(templateInputStreamReader);
 379                         } catch (TemplateException te1) {
 380                                 logger.log(Level.SEVERE, String.format("Could not parse template “%s”!", templateName), te1);
 381                                 return null;
 382                         } finally {
 383                                 Closer.close(templateInputStreamReader);
 384                                 Closer.close(templateInputStream);
 385                         }
 386
 387                         TemplateContext templateContext = templateContextFactory.createTemplateContext();
 388                         templateContext.set("core", core);
 389                         templateContext.set("currentSone", soneProperties);
 390                         templateContext.set("currentEdition", core.getUpdateChecker().getLatestEdition());
 391                         templateContext.set("version", SonePlugin.VERSION);
 392                         StringWriter writer = new StringWriter();
 393                         StringBucket bucket = null;
 394                         try {
 395                                 template.render(templateContext, writer);
 396                                 bucket = new StringBucket(writer.toString(), utf8Charset);
 397                                 return new ManifestElement(name, bucket, contentType, bucket.size());
 398                         } catch (TemplateException te1) {
 399                                 logger.log(Level.SEVERE, String.format("Could not render template “%s”!", templateName), te1);
 400                                 return null;
 401                         } finally {
 402                                 Closer.close(writer);
 403                                 if (bucket != null) {
 404                                         bucket.free();
 405                                 }
 406                         }
 407                 }
 408
 409         }
 410
 411 }