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

   1 /*
   2  * Sone - SoneInserter.java - Copyright © 2010–2020 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.concurrent.TimeUnit.*;
  23 import static java.util.logging.Logger.getLogger;
  24 import static net.pterodactylus.sone.data.Album.NOT_EMPTY;
  25
  26 import java.io.Closeable;
  27 import java.io.InputStream;
  28 import java.io.InputStreamReader;
  29 import java.io.StringWriter;
  30 import java.net.MalformedURLException;
  31 import java.nio.charset.Charset;
  32 import java.util.HashMap;
  33 import java.util.HashSet;
  34 import java.util.Map;
  35 import java.util.Set;
  36 import java.util.concurrent.atomic.AtomicInteger;
  37 import java.util.logging.Level;
  38 import java.util.logging.Logger;
  39
  40 import com.codahale.metrics.*;
  41 import com.google.common.base.*;
  42 import net.pterodactylus.sone.core.SoneModificationDetector.LockableFingerprintProvider;
  43 import net.pterodactylus.sone.core.event.InsertionDelayChangedEvent;
  44 import net.pterodactylus.sone.core.event.SoneInsertAbortedEvent;
  45 import net.pterodactylus.sone.core.event.SoneInsertedEvent;
  46 import net.pterodactylus.sone.core.event.SoneInsertingEvent;
  47 import net.pterodactylus.sone.data.Album;
  48 import net.pterodactylus.sone.data.Post;
  49 import net.pterodactylus.sone.data.Reply;
  50 import net.pterodactylus.sone.data.Sone;
  51 import net.pterodactylus.sone.data.Sone.SoneStatus;
  52 import net.pterodactylus.sone.freenet.wot.OwnIdentity;
  53 import net.pterodactylus.sone.main.SonePlugin;
  54 import net.pterodactylus.util.io.Closer;
  55 import net.pterodactylus.util.service.AbstractService;
  56 import net.pterodactylus.util.template.HtmlFilter;
  57 import net.pterodactylus.util.template.ReflectionAccessor;
  58 import net.pterodactylus.util.template.Template;
  59 import net.pterodactylus.util.template.TemplateContext;
  60 import net.pterodactylus.util.template.TemplateContextFactory;
  61 import net.pterodactylus.util.template.TemplateException;
  62 import net.pterodactylus.util.template.TemplateParser;
  63 import net.pterodactylus.util.template.XmlFilter;
  64
  65 import com.google.common.annotations.VisibleForTesting;
  66 import com.google.common.collect.FluentIterable;
  67 import com.google.common.collect.Ordering;
  68 import com.google.common.eventbus.EventBus;
  69 import com.google.common.eventbus.Subscribe;
  70
  71 import freenet.keys.FreenetURI;
  72 import freenet.support.api.Bucket;
  73 import freenet.support.api.ManifestElement;
  74 import freenet.support.api.RandomAccessBucket;
  75 import freenet.support.io.ArrayBucket;
  76
  77 /**
  78  * A Sone inserter is responsible for inserting a Sone if it has changed.
  79  */
  80 public class SoneInserter extends AbstractService {
  81
  82         /** The logger. */
  83         private static final Logger logger = getLogger(SoneInserter.class.getName());
  84
  85         /** The insertion delay (in seconds). */
  86         private static final AtomicInteger insertionDelay = new AtomicInteger(60);
  87
  88         /** The template factory used to create the templates. */
  89         private static final TemplateContextFactory templateContextFactory = new TemplateContextFactory();
  90
  91         static {
  92                 templateContextFactory.addAccessor(Object.class, new ReflectionAccessor());
  93                 templateContextFactory.addFilter("xml", new XmlFilter());
  94                 templateContextFactory.addFilter("html", new HtmlFilter());
  95         }
  96
  97         /** The UTF-8 charset. */
  98         private static final Charset utf8Charset = Charset.forName("UTF-8");
  99
 100         /** The core. */
 101         private final Core core;
 102
 103         /** The event bus. */
 104         private final EventBus eventBus;
 105
 106         /** The Freenet interface. */
 107         private final FreenetInterface freenetInterface;
 108
 109         private final SoneModificationDetector soneModificationDetector;
 110         private final long delay;
 111         private final String soneId;
 112         private final Histogram soneInsertDurationHistogram;
 113         private final Meter soneInsertErrorMeter;
 114
 115         /**
 116          * Creates a new Sone inserter.
 117          *
 118          * @param core
 119          *            The core
 120          * @param eventBus
 121          *            The event bus
 122          * @param freenetInterface
 123          *            The freenet interface
 124          * @param soneId
 125          *            The ID of the Sone to insert
 126          */
 127         public SoneInserter(final Core core, EventBus eventBus, FreenetInterface freenetInterface, MetricRegistry metricRegistry, final String soneId) {
 128                 this(core, eventBus, freenetInterface, metricRegistry, soneId, new SoneModificationDetector(new LockableFingerprintProvider() {
 129                         @Override
 130                         public boolean isLocked() {
 131                                 Sone sone = core.getSone(soneId);
 132                                 if (sone == null) {
 133                                         return false;
 134                                 }
 135                                 return core.isLocked(sone);
 136                         }
 137
 138                         @Override
 139                         public String getFingerprint() {
 140                                 Sone sone = core.getSone(soneId);
 141                                 if (sone == null) {
 142                                         return null;
 143                                 }
 144                                 return sone.getFingerprint();
 145                         }
 146                 }, insertionDelay), 1000);
 147         }
 148
 149         @VisibleForTesting
 150         SoneInserter(Core core, EventBus eventBus, FreenetInterface freenetInterface, MetricRegistry metricRegistry, String soneId, SoneModificationDetector soneModificationDetector, long delay) {
 151                 super("Sone Inserter for “" + soneId + "”", false);
 152                 this.core = core;
 153                 this.eventBus = eventBus;
 154                 this.freenetInterface = freenetInterface;
 155                 this.soneInsertDurationHistogram = metricRegistry.histogram("sone.insert.duration", () -> new Histogram(new ExponentiallyDecayingReservoir(3000, 0)));
 156                 this.soneInsertErrorMeter = metricRegistry.meter("sone.insert.errors");
 157                 this.soneId = soneId;
 158                 this.soneModificationDetector = soneModificationDetector;
 159                 this.delay = delay;
 160         }
 161
 162         //
 163         // ACCESSORS
 164         //
 165
 166         @VisibleForTesting
 167         static AtomicInteger getInsertionDelay() {
 168                 return insertionDelay;
 169         }
 170
 171         /**
 172          * Changes the insertion delay, i.e. the time the Sone inserter waits after it
 173          * has noticed a Sone modification before it starts the insert.
 174          *
 175          * @param insertionDelay
 176          *            The insertion delay (in seconds)
 177          */
 178         private static void setInsertionDelay(int insertionDelay) {
 179                 SoneInserter.insertionDelay.set(insertionDelay);
 180         }
 181
 182         /**
 183          * Returns the fingerprint of the last insert.
 184          *
 185          * @return The fingerprint of the last insert
 186          */
 187         public String getLastInsertFingerprint() {
 188                 return soneModificationDetector.getLastInsertFingerprint();
 189         }
 190
 191         /**
 192          * Sets the fingerprint of the last insert.
 193          *
 194          * @param lastInsertFingerprint
 195          *            The fingerprint of the last insert
 196          */
 197         public void setLastInsertFingerprint(String lastInsertFingerprint) {
 198                 soneModificationDetector.setFingerprint(lastInsertFingerprint);
 199         }
 200
 201         /**
 202          * Returns whether the Sone inserter has detected a modification of the
 203          * Sone.
 204          *
 205          * @return {@code true} if the Sone has been modified, {@code false}
 206          *         otherwise
 207          */
 208         public boolean isModified() {
 209                 return soneModificationDetector.isModified();
 210         }
 211
 212         //
 213         // SERVICE METHODS
 214         //
 215
 216         /**
 217          * {@inheritDoc}
 218          */
 219         @Override
 220         protected void serviceRun() {
 221                 while (!shouldStop()) {
 222                         try {
 223                                 /* check every second. */
 224                                 sleep(delay);
 225
 226                                 if (soneModificationDetector.isEligibleForInsert()) {
 227                                         Sone sone = core.getSone(soneId);
 228                                         if (sone == null) {
 229                                                 logger.log(Level.WARNING, format("Sone %s has disappeared, exiting inserter.", soneId));
 230                                                 return;
 231                                         }
 232                                         InsertInformation insertInformation = new InsertInformation(sone);
 233                                         logger.log(Level.INFO, String.format("Inserting Sone “%s”…", sone.getName()));
 234
 235                                         boolean success = false;
 236                                         try {
 237                                                 sone.setStatus(SoneStatus.inserting);
 238                                                 long insertTime = currentTimeMillis();
 239                                                 eventBus.post(new SoneInsertingEvent(sone));
 240                                                 Stopwatch stopwatch = Stopwatch.createStarted();
 241                                                 FreenetURI finalUri = freenetInterface.insertDirectory(getSoneInsertUri(sone), insertInformation.generateManifestEntries(), "index.html");
 242                                                 stopwatch.stop();
 243                                                 soneInsertDurationHistogram.update(stopwatch.elapsed(MICROSECONDS));
 244                                                 eventBus.post(new SoneInsertedEvent(sone, stopwatch.elapsed(MILLISECONDS), insertInformation.getFingerprint()));
 245                                                 /* at this point we might already be stopped. */
 246                                                 if (shouldStop()) {
 247                                                         /* if so, bail out, don’t change anything. */
 248                                                         break;
 249                                                 }
 250                                                 sone.setTime(insertTime);
 251                                                 sone.setLatestEdition(finalUri.getEdition());
 252                                                 core.touchConfiguration();
 253                                                 success = true;
 254                                                 logger.log(Level.INFO, String.format("Inserted Sone “%s” at %s.", sone.getName(), finalUri));
 255                                         } catch (SoneException se1) {
 256                                                 soneInsertErrorMeter.mark();
 257                                                 eventBus.post(new SoneInsertAbortedEvent(sone, se1));
 258                                                 logger.log(Level.WARNING, String.format("Could not insert Sone “%s”!", sone.getName()), se1);
 259                                         } finally {
 260                                                 insertInformation.close();
 261                                                 sone.setStatus(SoneStatus.idle);
 262                                         }
 263
 264                                         /*
 265                                          * reset modification counter if Sone has not been modified
 266                                          * while it was inserted.
 267                                          */
 268                                         if (success) {
 269                                                 synchronized (sone) {
 270                                                         if (insertInformation.getFingerprint().equals(sone.getFingerprint())) {
 271                                                                 logger.log(Level.FINE, String.format("Sone “%s” was not modified further, resetting counter…", sone));
 272                                                                 soneModificationDetector.setFingerprint(insertInformation.getFingerprint());
 273                                                                 core.touchConfiguration();
 274                                                         }
 275                                                 }
 276                                         }
 277                                 }
 278                         } catch (Throwable t1) {
 279                                 logger.log(Level.SEVERE, "SoneInserter threw an Exception!", t1);
 280                         }
 281                 }
 282         }
 283
 284         @Subscribe
 285         public void insertionDelayChanged(InsertionDelayChangedEvent insertionDelayChangedEvent) {
 286                 setInsertionDelay(insertionDelayChangedEvent.getInsertionDelay());
 287         }
 288
 289         private FreenetURI getSoneInsertUri(Sone sone) throws MalformedURLException {
 290                 return new FreenetURI(((OwnIdentity) sone.getIdentity()).getInsertUri())
 291                                 .setKeyType("USK")
 292                                 .setDocName("Sone")
 293                                 .setMetaString(new String[0])
 294                                 .setSuggestedEdition(sone.getLatestEdition());
 295         }
 296
 297         /**
 298          * Container for information that are required to insert a Sone. This
 299          * container merely exists to copy all relevant data without holding a lock
 300          * on the {@link Sone} object for too long.
 301          */
 302         @VisibleForTesting
 303         class InsertInformation implements Closeable {
 304
 305                 /** All properties of the Sone, copied for thread safety. */
 306                 private final Map<String, Object> soneProperties = new HashMap<>();
 307                 private final String fingerprint;
 308                 private final ManifestCreator manifestCreator;
 309
 310                 /**
 311                  * Creates a new insert information container.
 312                  *
 313                  * @param sone
 314                  *            The sone to insert
 315                  */
 316                 public InsertInformation(Sone sone) {
 317                         this.fingerprint = sone.getFingerprint();
 318                         Map<String, Object> soneProperties = new HashMap<>();
 319                         soneProperties.put("id", sone.getId());
 320                         soneProperties.put("name", sone.getName());
 321                         soneProperties.put("time", currentTimeMillis());
 322                         soneProperties.put("requestUri", sone.getRequestUri());
 323                         soneProperties.put("profile", sone.getProfile());
 324                         soneProperties.put("posts", Ordering.from(Post.NEWEST_FIRST).sortedCopy(sone.getPosts()));
 325                         soneProperties.put("replies", Ordering.from(Reply.TIME_COMPARATOR).reverse().sortedCopy(sone.getReplies()));
 326                         soneProperties.put("likedPostIds", new HashSet<>(sone.getLikedPostIds()));
 327                         soneProperties.put("likedReplyIds", new HashSet<>(sone.getLikedReplyIds()));
 328                         soneProperties.put("albums", FluentIterable.from(sone.getRootAlbum().getAlbums()).transformAndConcat(Album.FLATTENER).filter(NOT_EMPTY).toList());
 329                         manifestCreator = new ManifestCreator(core, soneProperties);
 330                 }
 331
 332                 //
 333                 // ACCESSORS
 334                 //
 335
 336                 @VisibleForTesting
 337                 String getFingerprint() {
 338                         return fingerprint;
 339                 }
 340
 341                 //
 342                 // ACTIONS
 343                 //
 344
 345                 /**
 346                  * Generates all manifest entries required to insert this Sone.
 347                  *
 348                  * @return The manifest entries for the Sone insert
 349                  */
 350                 public HashMap<String, Object> generateManifestEntries() {
 351                         HashMap<String, Object> manifestEntries = new HashMap<>();
 352
 353                         /* first, create an index.html. */
 354                         manifestEntries.put("index.html", manifestCreator.createManifestElement(
 355                                         "index.html", "text/html; charset=utf-8",
 356                                         "/templates/insert/index.html"));
 357
 358                         /* now, store the sone. */
 359                         manifestEntries.put("sone.xml", manifestCreator.createManifestElement(
 360                                         "sone.xml", "text/xml; charset=utf-8",
 361                                         "/templates/insert/sone.xml"));
 362
 363                         return manifestEntries;
 364                 }
 365
 366                 @Override
 367                 public void close() {
 368                         manifestCreator.close();
 369                 }
 370
 371         }
 372
 373         /**
 374          * Creates manifest elements for an insert by rendering a template.
 375          */
 376         @VisibleForTesting
 377         static class ManifestCreator implements Closeable {
 378
 379                 private final Core core;
 380                 private final Map<String, Object> soneProperties;
 381                 private final Set<Bucket> buckets = new HashSet<>();
 382
 383                 ManifestCreator(Core core, Map<String, Object> soneProperties) {
 384                         this.core = core;
 385                         this.soneProperties = soneProperties;
 386                 }
 387
 388                 public ManifestElement createManifestElement(String name, String contentType, String templateName) {
 389                         InputStreamReader templateInputStreamReader = null;
 390                         InputStream templateInputStream = null;
 391                         Template template;
 392                         try {
 393                                 templateInputStream = getClass().getResourceAsStream(templateName);
 394                                 templateInputStreamReader = new InputStreamReader(templateInputStream, utf8Charset);
 395                                 template = TemplateParser.parse(templateInputStreamReader);
 396                         } catch (TemplateException te1) {
 397                                 logger.log(Level.SEVERE, String.format("Could not parse template “%s”!", templateName), te1);
 398                                 return null;
 399                         } finally {
 400                                 Closer.close(templateInputStreamReader);
 401                                 Closer.close(templateInputStream);
 402                         }
 403
 404                         TemplateContext templateContext = templateContextFactory.createTemplateContext();
 405                         templateContext.set("core", core);
 406                         templateContext.set("currentSone", soneProperties);
 407                         templateContext.set("currentEdition", core.getUpdateChecker().getLatestEdition());
 408                         templateContext.set("version", SonePlugin.getPluginVersion());
 409                         StringWriter writer = new StringWriter();
 410                         try {
 411                                 template.render(templateContext, writer);
 412                                 RandomAccessBucket bucket = new ArrayBucket(writer.toString().getBytes(Charsets.UTF_8));
 413                                 buckets.add(bucket);
 414                                 return new ManifestElement(name, bucket, contentType, bucket.size());
 415                         } catch (TemplateException te1) {
 416                                 logger.log(Level.SEVERE, String.format("Could not render template “%s”!", templateName), te1);
 417                                 return null;
 418                         } finally {
 419                                 Closer.close(writer);
 420                         }
 421                 }
 422
 423                 public void close() {
 424                         for (Bucket bucket : buckets) {
 425                                 bucket.free();
 426                         }
 427                 }
 428
 429         }
 430
 431 }