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

   1 /*
   2  * Sone - SoneInserter.java - Copyright © 2010–2016 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.Closeable;
  26 import java.io.InputStream;
  27 import java.io.InputStreamReader;
  28 import java.io.StringWriter;
  29 import java.nio.charset.Charset;
  30 import java.util.HashMap;
  31 import java.util.HashSet;
  32 import java.util.Map;
  33 import java.util.Set;
  34 import java.util.concurrent.atomic.AtomicInteger;
  35 import java.util.logging.Level;
  36 import java.util.logging.Logger;
  37
  38 import net.pterodactylus.sone.core.SoneModificationDetector.LockableFingerprintProvider;
  39 import net.pterodactylus.sone.core.event.InsertionDelayChangedEvent;
  40 import net.pterodactylus.sone.core.event.SoneInsertAbortedEvent;
  41 import net.pterodactylus.sone.core.event.SoneInsertedEvent;
  42 import net.pterodactylus.sone.core.event.SoneInsertingEvent;
  43 import net.pterodactylus.sone.data.Album;
  44 import net.pterodactylus.sone.data.Post;
  45 import net.pterodactylus.sone.data.Reply;
  46 import net.pterodactylus.sone.data.Sone;
  47 import net.pterodactylus.sone.data.Sone.SoneStatus;
  48 import net.pterodactylus.sone.main.SonePlugin;
  49 import net.pterodactylus.util.io.Closer;
  50 import net.pterodactylus.util.service.AbstractService;
  51 import net.pterodactylus.util.template.HtmlFilter;
  52 import net.pterodactylus.util.template.ReflectionAccessor;
  53 import net.pterodactylus.util.template.Template;
  54 import net.pterodactylus.util.template.TemplateContext;
  55 import net.pterodactylus.util.template.TemplateContextFactory;
  56 import net.pterodactylus.util.template.TemplateException;
  57 import net.pterodactylus.util.template.TemplateParser;
  58 import net.pterodactylus.util.template.XmlFilter;
  59
  60 import com.google.common.annotations.VisibleForTesting;
  61 import com.google.common.base.Charsets;
  62 import com.google.common.collect.FluentIterable;
  63 import com.google.common.collect.Ordering;
  64 import com.google.common.eventbus.EventBus;
  65 import com.google.common.eventbus.Subscribe;
  66
  67 import freenet.keys.FreenetURI;
  68 import freenet.support.api.Bucket;
  69 import freenet.support.api.ManifestElement;
  70 import freenet.support.api.RandomAccessBucket;
  71 import freenet.support.io.ArrayBucket;
  72
  73 /**
  74  * A Sone inserter is responsible for inserting a Sone if it has changed.
  75  */
  76 public class SoneInserter extends AbstractService {
  77
  78         /** The logger. */
  79         private static final Logger logger = getLogger(SoneInserter.class.getName());
  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
 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, final String soneId) {
 122                 this(core, eventBus, freenetInterface, soneId, new SoneModificationDetector(new LockableFingerprintProvider() {
 123                         @Override
 124                         public boolean isLocked() {
 125                                 Sone sone = core.getSone(soneId);
 126                                 if (sone == null) {
 127                                         return false;
 128                                 }
 129                                 return core.isLocked(sone);
 130                         }
 131
 132                         @Override
 133                         public String getFingerprint() {
 134                                 Sone sone = core.getSone(soneId);
 135                                 if (sone == null) {
 136                                         return null;
 137                                 }
 138                                 return sone.getFingerprint();
 139                         }
 140                 }, insertionDelay), 1000);
 141         }
 142
 143         @VisibleForTesting
 144         SoneInserter(Core core, EventBus eventBus, FreenetInterface freenetInterface, 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.soneId = soneId;
 150                 this.soneModificationDetector = soneModificationDetector;
 151                 this.delay = delay;
 152         }
 153
 154         //
 155         // ACCESSORS
 156         //
 157
 158         @VisibleForTesting
 159         static AtomicInteger getInsertionDelay() {
 160                 return insertionDelay;
 161         }
 162
 163         /**
 164          * Changes the insertion delay, i.e. the time the Sone inserter waits after it
 165          * has noticed a Sone modification before it starts the insert.
 166          *
 167          * @param insertionDelay
 168          *            The insertion delay (in seconds)
 169          */
 170         private static void setInsertionDelay(int insertionDelay) {
 171                 SoneInserter.insertionDelay.set(insertionDelay);
 172         }
 173
 174         /**
 175          * Returns the fingerprint of the last insert.
 176          *
 177          * @return The fingerprint of the last insert
 178          */
 179         public String getLastInsertFingerprint() {
 180                 return soneModificationDetector.getLastInsertFingerprint();
 181         }
 182
 183         /**
 184          * Sets the fingerprint of the last insert.
 185          *
 186          * @param lastInsertFingerprint
 187          *            The fingerprint of the last insert
 188          */
 189         public void setLastInsertFingerprint(String lastInsertFingerprint) {
 190                 soneModificationDetector.setFingerprint(lastInsertFingerprint);
 191         }
 192
 193         /**
 194          * Returns whether the Sone inserter has detected a modification of the
 195          * Sone.
 196          *
 197          * @return {@code true} if the Sone has been modified, {@code false}
 198          *         otherwise
 199          */
 200         public boolean isModified() {
 201                 return soneModificationDetector.isModified();
 202         }
 203
 204         //
 205         // SERVICE METHODS
 206         //
 207
 208         /**
 209          * {@inheritDoc}
 210          */
 211         @Override
 212         protected void serviceRun() {
 213                 while (!shouldStop()) {
 214                         try {
 215                                 /* check every second. */
 216                                 sleep(delay);
 217
 218                                 if (soneModificationDetector.isEligibleForInsert()) {
 219                                         Sone sone = core.getSone(soneId);
 220                                         if (sone == null) {
 221                                                 logger.log(Level.WARNING, format("Sone %s has disappeared, exiting inserter.", soneId));
 222                                                 return;
 223                                         }
 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(sone.getInsertUri(), insertInformation.generateManifestEntries(), "index.html");
 233                                                 eventBus.post(new SoneInsertedEvent(sone, currentTimeMillis() - insertTime, insertInformation.getFingerprint()));
 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                                                 insertInformation.close();
 249                                                 sone.setStatus(SoneStatus.idle);
 250                                         }
 251
 252                                         /*
 253                                          * reset modification counter if Sone has not been modified
 254                                          * while it was inserted.
 255                                          */
 256                                         if (success) {
 257                                                 synchronized (sone) {
 258                                                         if (insertInformation.getFingerprint().equals(sone.getFingerprint())) {
 259                                                                 logger.log(Level.FINE, String.format("Sone “%s” was not modified further, resetting counter…", sone));
 260                                                                 soneModificationDetector.setFingerprint(insertInformation.getFingerprint());
 261                                                                 core.touchConfiguration();
 262                                                         }
 263                                                 }
 264                                         }
 265                                 }
 266                         } catch (Throwable t1) {
 267                                 logger.log(Level.SEVERE, "SoneInserter threw an Exception!", t1);
 268                         }
 269                 }
 270         }
 271
 272         @Subscribe
 273         public void insertionDelayChanged(InsertionDelayChangedEvent insertionDelayChangedEvent) {
 274                 setInsertionDelay(insertionDelayChangedEvent.getInsertionDelay());
 275         }
 276
 277         /**
 278          * Container for information that are required to insert a Sone. This
 279          * container merely exists to copy all relevant data without holding a lock
 280          * on the {@link Sone} object for too long.
 281          */
 282         @VisibleForTesting
 283         class InsertInformation implements Closeable {
 284
 285                 /** All properties of the Sone, copied for thread safety. */
 286                 private final Map<String, Object> soneProperties = new HashMap<String, Object>();
 287                 private final String fingerprint;
 288                 private final ManifestCreator manifestCreator;
 289
 290                 /**
 291                  * Creates a new insert information container.
 292                  *
 293                  * @param sone
 294                  *            The sone to insert
 295                  */
 296                 public InsertInformation(Sone sone) {
 297                         this.fingerprint = sone.getFingerprint();
 298                         Map<String, Object> soneProperties = new HashMap<String, Object>();
 299                         soneProperties.put("id", sone.getId());
 300                         soneProperties.put("name", sone.getName());
 301                         soneProperties.put("time", currentTimeMillis());
 302                         soneProperties.put("requestUri", sone.getRequestUri());
 303                         soneProperties.put("profile", sone.getProfile());
 304                         soneProperties.put("posts", Ordering.from(Post.NEWEST_FIRST).sortedCopy(sone.getPosts()));
 305                         soneProperties.put("replies", Ordering.from(Reply.TIME_COMPARATOR).reverse().sortedCopy(sone.getReplies()));
 306                         soneProperties.put("likedPostIds", new HashSet<String>(sone.getLikedPostIds()));
 307                         soneProperties.put("likedReplyIds", new HashSet<String>(sone.getLikedReplyIds()));
 308                         soneProperties.put("albums", FluentIterable.from(sone.getRootAlbum().getAlbums()).transformAndConcat(Album.FLATTENER).filter(NOT_EMPTY).toList());
 309                         manifestCreator = new ManifestCreator(core, soneProperties);
 310                 }
 311
 312                 //
 313                 // ACCESSORS
 314                 //
 315
 316                 @VisibleForTesting
 317                 String getFingerprint() {
 318                         return fingerprint;
 319                 }
 320
 321                 //
 322                 // ACTIONS
 323                 //
 324
 325                 /**
 326                  * Generates all manifest entries required to insert this Sone.
 327                  *
 328                  * @return The manifest entries for the Sone insert
 329                  */
 330                 public HashMap<String, Object> generateManifestEntries() {
 331                         HashMap<String, Object> manifestEntries = new HashMap<String, Object>();
 332
 333                         /* first, create an index.html. */
 334                         manifestEntries.put("index.html", manifestCreator.createManifestElement(
 335                                         "index.html", "text/html; charset=utf-8",
 336                                         "/templates/insert/index.html"));
 337
 338                         /* now, store the sone. */
 339                         manifestEntries.put("sone.xml", manifestCreator.createManifestElement(
 340                                         "sone.xml", "text/xml; charset=utf-8",
 341                                         "/templates/insert/sone.xml"));
 342
 343                         return manifestEntries;
 344                 }
 345
 346                 @Override
 347                 public void close() {
 348                         manifestCreator.close();
 349                 }
 350
 351         }
 352
 353         /**
 354          * Creates manifest elements for an insert by rendering a template.
 355          */
 356         @VisibleForTesting
 357         static class ManifestCreator implements Closeable {
 358
 359                 private final Core core;
 360                 private final Map<String, Object> soneProperties;
 361                 private final Set<Bucket> buckets = new HashSet<Bucket>();
 362
 363                 ManifestCreator(Core core, Map<String, Object> soneProperties) {
 364                         this.core = core;
 365                         this.soneProperties = soneProperties;
 366                 }
 367
 368                 public ManifestElement createManifestElement(String name, String contentType, String templateName) {
 369                         InputStreamReader templateInputStreamReader = null;
 370                         InputStream templateInputStream = null;
 371                         Template template;
 372                         try {
 373                                 templateInputStream = getClass().getResourceAsStream(templateName);
 374                                 templateInputStreamReader = new InputStreamReader(templateInputStream, utf8Charset);
 375                                 template = TemplateParser.parse(templateInputStreamReader);
 376                         } catch (TemplateException te1) {
 377                                 logger.log(Level.SEVERE, String.format("Could not parse template “%s”!", templateName), te1);
 378                                 return null;
 379                         } finally {
 380                                 Closer.close(templateInputStreamReader);
 381                                 Closer.close(templateInputStream);
 382                         }
 383
 384                         TemplateContext templateContext = templateContextFactory.createTemplateContext();
 385                         templateContext.set("core", core);
 386                         templateContext.set("currentSone", soneProperties);
 387                         templateContext.set("currentEdition", core.getUpdateChecker().getLatestEdition());
 388                         templateContext.set("version", SonePlugin.getPluginVersion());
 389                         StringWriter writer = new StringWriter();
 390                         try {
 391                                 template.render(templateContext, writer);
 392                                 RandomAccessBucket bucket = new ArrayBucket(writer.toString().getBytes(Charsets.UTF_8));
 393                                 buckets.add(bucket);
 394                                 return new ManifestElement(name, bucket, contentType, bucket.size());
 395                         } catch (TemplateException te1) {
 396                                 logger.log(Level.SEVERE, String.format("Could not render template “%s”!", templateName), te1);
 397                                 return null;
 398                         } finally {
 399                                 Closer.close(writer);
 400                         }
 401                 }
 402
 403                 public void close() {
 404                         for (Bucket bucket : buckets) {
 405                                 bucket.free();
 406                         }
 407                 }
 408
 409         }
 410
 411 }