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