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