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  * @author <a href="mailto:bombe@pterodactylus.net">David ‘Bombe’ Roden</a>
  77  */
  78 public class SoneInserter extends AbstractService {
  79
  80         /** The logger. */
  81         private static final Logger logger = getLogger(SoneInserter.class.getName());
  82
  83         /** The insertion delay (in seconds). */
  84         private static final AtomicInteger insertionDelay = new AtomicInteger(60);
  85
  86         /** The template factory used to create the templates. */
  87         private static final TemplateContextFactory templateContextFactory = new TemplateContextFactory();
  88
  89         static {
  90                 templateContextFactory.addAccessor(Object.class, new ReflectionAccessor());
  91                 templateContextFactory.addFilter("xml", new XmlFilter());
  92                 templateContextFactory.addFilter("html", new HtmlFilter());
  93         }
  94
  95         /** The UTF-8 charset. */
  96         private static final Charset utf8Charset = Charset.forName("UTF-8");
  97
  98         /** The core. */
  99         private final Core core;
 100
 101         /** The event bus. */
 102         private final EventBus eventBus;
 103
 104         /** The Freenet interface. */
 105         private final FreenetInterface freenetInterface;
 106
 107         private final SoneModificationDetector soneModificationDetector;
 108         private final long delay;
 109         private final String soneId;
 110
 111         /**
 112          * Creates a new Sone inserter.
 113          *
 114          * @param core
 115          *            The core
 116          * @param eventBus
 117          *            The event bus
 118          * @param freenetInterface
 119          *            The freenet interface
 120          * @param soneId
 121          *            The ID of the Sone to insert
 122          */
 123         public SoneInserter(final Core core, EventBus eventBus, FreenetInterface freenetInterface, final String soneId) {
 124                 this(core, eventBus, freenetInterface, soneId, new SoneModificationDetector(new LockableFingerprintProvider() {
 125                         @Override
 126                         public boolean isLocked() {
 127                                 Sone sone = core.getSone(soneId);
 128                                 if (sone == null) {
 129                                         return false;
 130                                 }
 131                                 return core.isLocked(sone);
 132                         }
 133
 134                         @Override
 135                         public String getFingerprint() {
 136                                 Sone sone = core.getSone(soneId);
 137                                 if (sone == null) {
 138                                         return null;
 139                                 }
 140                                 return sone.getFingerprint();
 141                         }
 142                 }, insertionDelay), 1000);
 143         }
 144
 145         @VisibleForTesting
 146         SoneInserter(Core core, EventBus eventBus, FreenetInterface freenetInterface, String soneId, SoneModificationDetector soneModificationDetector, long delay) {
 147                 super("Sone Inserter for “" + soneId + "”", false);
 148                 this.core = core;
 149                 this.eventBus = eventBus;
 150                 this.freenetInterface = freenetInterface;
 151                 this.soneId = soneId;
 152                 this.soneModificationDetector = soneModificationDetector;
 153                 this.delay = delay;
 154         }
 155
 156         //
 157         // ACCESSORS
 158         //
 159
 160         @VisibleForTesting
 161         static AtomicInteger getInsertionDelay() {
 162                 return insertionDelay;
 163         }
 164
 165         /**
 166          * Changes the insertion delay, i.e. the time the Sone inserter waits after it
 167          * has noticed a Sone modification before it starts the insert.
 168          *
 169          * @param insertionDelay
 170          *            The insertion delay (in seconds)
 171          */
 172         private static void setInsertionDelay(int insertionDelay) {
 173                 SoneInserter.insertionDelay.set(insertionDelay);
 174         }
 175
 176         /**
 177          * Returns the fingerprint of the last insert.
 178          *
 179          * @return The fingerprint of the last insert
 180          */
 181         public String getLastInsertFingerprint() {
 182                 return soneModificationDetector.getLastInsertFingerprint();
 183         }
 184
 185         /**
 186          * Sets the fingerprint of the last insert.
 187          *
 188          * @param lastInsertFingerprint
 189          *            The fingerprint of the last insert
 190          */
 191         public void setLastInsertFingerprint(String lastInsertFingerprint) {
 192                 soneModificationDetector.setFingerprint(lastInsertFingerprint);
 193         }
 194
 195         /**
 196          * Returns whether the Sone inserter has detected a modification of the
 197          * Sone.
 198          *
 199          * @return {@code true} if the Sone has been modified, {@code false}
 200          *         otherwise
 201          */
 202         public boolean isModified() {
 203                 return soneModificationDetector.isModified();
 204         }
 205
 206         //
 207         // SERVICE METHODS
 208         //
 209
 210         /**
 211          * {@inheritDoc}
 212          */
 213         @Override
 214         protected void serviceRun() {
 215                 while (!shouldStop()) {
 216                         try {
 217                                 /* check every second. */
 218                                 sleep(delay);
 219
 220                                 if (soneModificationDetector.isEligibleForInsert()) {
 221                                         Sone sone = core.getSone(soneId);
 222                                         if (sone == null) {
 223                                                 logger.log(Level.WARNING, format("Sone %s has disappeared, exiting inserter.", soneId));
 224                                                 return;
 225                                         }
 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                                                 sone.setTime(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                                                 insertInformation.close();
 251                                                 sone.setStatus(SoneStatus.idle);
 252                                         }
 253
 254                                         /*
 255                                          * reset modification counter if Sone has not been modified
 256                                          * while it was inserted.
 257                                          */
 258                                         if (success) {
 259                                                 synchronized (sone) {
 260                                                         if (insertInformation.getFingerprint().equals(sone.getFingerprint())) {
 261                                                                 logger.log(Level.FINE, String.format("Sone “%s” was not modified further, resetting counter…", sone));
 262                                                                 soneModificationDetector.setFingerprint(insertInformation.getFingerprint());
 263                                                                 core.touchConfiguration();
 264                                                         }
 265                                                 }
 266                                         }
 267                                 }
 268                         } catch (Throwable t1) {
 269                                 logger.log(Level.SEVERE, "SoneInserter threw an Exception!", t1);
 270                         }
 271                 }
 272         }
 273
 274         @Subscribe
 275         public void insertionDelayChanged(InsertionDelayChangedEvent insertionDelayChangedEvent) {
 276                 setInsertionDelay(insertionDelayChangedEvent.getInsertionDelay());
 277         }
 278
 279         /**
 280          * Container for information that are required to insert a Sone. This
 281          * container merely exists to copy all relevant data without holding a lock
 282          * on the {@link Sone} object for too long.
 283          *
 284          * @author <a href="mailto:bombe@pterodactylus.net">David ‘Bombe’ Roden</a>
 285          */
 286         @VisibleForTesting
 287         class InsertInformation implements Closeable {
 288
 289                 /** All properties of the Sone, copied for thread safety. */
 290                 private final Map<String, Object> soneProperties = new HashMap<String, Object>();
 291                 private final String fingerprint;
 292                 private final ManifestCreator manifestCreator;
 293
 294                 /**
 295                  * Creates a new insert information container.
 296                  *
 297                  * @param sone
 298                  *            The sone to insert
 299                  */
 300                 public InsertInformation(Sone sone) {
 301                         this.fingerprint = sone.getFingerprint();
 302                         Map<String, Object> soneProperties = new HashMap<String, Object>();
 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("profile", sone.getProfile());
 308                         soneProperties.put("posts", Ordering.from(Post.NEWEST_FIRST).sortedCopy(sone.getPosts()));
 309                         soneProperties.put("replies", Ordering.from(Reply.TIME_COMPARATOR).reverse().sortedCopy(sone.getReplies()));
 310                         soneProperties.put("likedPostIds", new HashSet<String>(sone.getLikedPostIds()));
 311                         soneProperties.put("likedReplyIds", new HashSet<String>(sone.getLikedReplyIds()));
 312                         soneProperties.put("albums", FluentIterable.from(sone.getRootAlbum().getAlbums()).transformAndConcat(Album.FLATTENER).filter(NOT_EMPTY).toList());
 313                         manifestCreator = new ManifestCreator(core, soneProperties);
 314                 }
 315
 316                 //
 317                 // ACCESSORS
 318                 //
 319
 320                 @VisibleForTesting
 321                 String getFingerprint() {
 322                         return fingerprint;
 323                 }
 324
 325                 //
 326                 // ACTIONS
 327                 //
 328
 329                 /**
 330                  * Generates all manifest entries required to insert this Sone.
 331                  *
 332                  * @return The manifest entries for the Sone insert
 333                  */
 334                 public HashMap<String, Object> generateManifestEntries() {
 335                         HashMap<String, Object> manifestEntries = new HashMap<String, Object>();
 336
 337                         /* first, create an index.html. */
 338                         manifestEntries.put("index.html", manifestCreator.createManifestElement(
 339                                         "index.html", "text/html; charset=utf-8",
 340                                         "/templates/insert/index.html"));
 341
 342                         /* now, store the sone. */
 343                         manifestEntries.put("sone.xml", manifestCreator.createManifestElement(
 344                                         "sone.xml", "text/xml; charset=utf-8",
 345                                         "/templates/insert/sone.xml"));
 346
 347                         return manifestEntries;
 348                 }
 349
 350                 @Override
 351                 public void close() {
 352                         manifestCreator.close();
 353                 }
 354
 355         }
 356
 357         /**
 358          * Creates manifest elements for an insert by rendering a template.
 359          *
 360          * @author <a href="mailto:bombe@pterodactylus.net">David ‘Bombe’ Roden</a>
 361          */
 362         @VisibleForTesting
 363         static class ManifestCreator implements Closeable {
 364
 365                 private final Core core;
 366                 private final Map<String, Object> soneProperties;
 367                 private final Set<Bucket> buckets = new HashSet<Bucket>();
 368
 369                 ManifestCreator(Core core, Map<String, Object> soneProperties) {
 370                         this.core = core;
 371                         this.soneProperties = soneProperties;
 372                 }
 373
 374                 public ManifestElement createManifestElement(String name, String contentType, String templateName) {
 375                         InputStreamReader templateInputStreamReader = null;
 376                         InputStream templateInputStream = null;
 377                         Template template;
 378                         try {
 379                                 templateInputStream = getClass().getResourceAsStream(templateName);
 380                                 templateInputStreamReader = new InputStreamReader(templateInputStream, utf8Charset);
 381                                 template = TemplateParser.parse(templateInputStreamReader);
 382                         } catch (TemplateException te1) {
 383                                 logger.log(Level.SEVERE, String.format("Could not parse template “%s”!", templateName), te1);
 384                                 return null;
 385                         } finally {
 386                                 Closer.close(templateInputStreamReader);
 387                                 Closer.close(templateInputStream);
 388                         }
 389
 390                         TemplateContext templateContext = templateContextFactory.createTemplateContext();
 391                         templateContext.set("core", core);
 392                         templateContext.set("currentSone", soneProperties);
 393                         templateContext.set("currentEdition", core.getUpdateChecker().getLatestEdition());
 394                         templateContext.set("version", SonePlugin.getPluginVersion());
 395                         StringWriter writer = new StringWriter();
 396                         try {
 397                                 template.render(templateContext, writer);
 398                                 RandomAccessBucket bucket = new ArrayBucket(writer.toString().getBytes(Charsets.UTF_8));
 399                                 buckets.add(bucket);
 400                                 return new ManifestElement(name, bucket, contentType, bucket.size());
 401                         } catch (TemplateException te1) {
 402                                 logger.log(Level.SEVERE, String.format("Could not render template “%s”!", templateName), te1);
 403                                 return null;
 404                         } finally {
 405                                 Closer.close(writer);
 406                         }
 407                 }
 408
 409                 public void close() {
 410                         for (Bucket bucket : buckets) {
 411                                 bucket.free();
 412                         }
 413                 }
 414
 415         }
 416
 417 }