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

   1 /*
   2  * Sone - SoneInserter.java - Copyright © 2010 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 java.io.InputStreamReader;
  21 import java.io.StringWriter;
  22 import java.nio.charset.Charset;
  23 import java.util.ArrayList;
  24 import java.util.HashMap;
  25 import java.util.HashSet;
  26 import java.util.Map;
  27 import java.util.logging.Level;
  28 import java.util.logging.Logger;
  29
  30 import net.pterodactylus.sone.core.Core.SoneStatus;
  31 import net.pterodactylus.sone.data.Post;
  32 import net.pterodactylus.sone.data.PostReply;
  33 import net.pterodactylus.sone.data.Reply;
  34 import net.pterodactylus.sone.data.Sone;
  35 import net.pterodactylus.sone.freenet.StringBucket;
  36 import net.pterodactylus.sone.main.SonePlugin;
  37 import net.pterodactylus.util.collection.ListBuilder;
  38 import net.pterodactylus.util.collection.ReverseComparator;
  39 import net.pterodactylus.util.io.Closer;
  40 import net.pterodactylus.util.logging.Logging;
  41 import net.pterodactylus.util.service.AbstractService;
  42 import net.pterodactylus.util.template.HtmlFilter;
  43 import net.pterodactylus.util.template.ReflectionAccessor;
  44 import net.pterodactylus.util.template.Template;
  45 import net.pterodactylus.util.template.TemplateContext;
  46 import net.pterodactylus.util.template.TemplateContextFactory;
  47 import net.pterodactylus.util.template.TemplateException;
  48 import net.pterodactylus.util.template.TemplateParser;
  49 import net.pterodactylus.util.template.XmlFilter;
  50 import freenet.client.async.ManifestElement;
  51 import freenet.keys.FreenetURI;
  52
  53 /**
  54  * A Sone inserter is responsible for inserting a Sone if it has changed.
  55  *
  56  * @author <a href="mailto:bombe@pterodactylus.net">David ‘Bombe’ Roden</a>
  57  */
  58 public class SoneInserter extends AbstractService {
  59
  60         /** The logger. */
  61         private static final Logger logger = Logging.getLogger(SoneInserter.class);
  62
  63         /** The insertion delay (in seconds). */
  64         private static volatile int insertionDelay = 60;
  65
  66         /** The template factory used to create the templates. */
  67         private static final TemplateContextFactory templateContextFactory = new TemplateContextFactory();
  68
  69         static {
  70                 templateContextFactory.addAccessor(Object.class, new ReflectionAccessor());
  71                 templateContextFactory.addFilter("xml", new XmlFilter());
  72                 templateContextFactory.addFilter("html", new HtmlFilter());
  73         }
  74
  75         /** The UTF-8 charset. */
  76         private static final Charset utf8Charset = Charset.forName("UTF-8");
  77
  78         /** The core. */
  79         private final Core core;
  80
  81         /** The Freenet interface. */
  82         private final FreenetInterface freenetInterface;
  83
  84         /** The Sone to insert. */
  85         private final Sone sone;
  86
  87         /** The insert listener manager. */
  88         private SoneInsertListenerManager soneInsertListenerManager;
  89
  90         /** Whether a modification has been detected. */
  91         private volatile boolean modified = false;
  92
  93         /** The fingerprint of the last insert. */
  94         private volatile String lastInsertFingerprint;
  95
  96         /**
  97          * Creates a new Sone inserter.
  98          *
  99          * @param core
 100          *            The core
 101          * @param freenetInterface
 102          *            The freenet interface
 103          * @param sone
 104          *            The Sone to insert
 105          */
 106         public SoneInserter(Core core, FreenetInterface freenetInterface, Sone sone) {
 107                 super("Sone Inserter for “" + sone.getName() + "”", false);
 108                 this.core = core;
 109                 this.freenetInterface = freenetInterface;
 110                 this.sone = sone;
 111                 this.soneInsertListenerManager = new SoneInsertListenerManager(sone);
 112         }
 113
 114         //
 115         // LISTENER MANAGEMENT
 116         //
 117
 118         /**
 119          * Adds a listener for Sone insert events.
 120          *
 121          * @param soneInsertListener
 122          *            The Sone insert listener
 123          */
 124         public void addSoneInsertListener(SoneInsertListener soneInsertListener) {
 125                 soneInsertListenerManager.addListener(soneInsertListener);
 126         }
 127
 128         /**
 129          * Removes a listener for Sone insert events.
 130          *
 131          * @param soneInsertListener
 132          *            The Sone insert listener
 133          */
 134         public void removeSoneInsertListener(SoneInsertListener soneInsertListener) {
 135                 soneInsertListenerManager.removeListener(soneInsertListener);
 136         }
 137
 138         //
 139         // ACCESSORS
 140         //
 141
 142         /**
 143          * Changes the insertion delay, i.e. the time the Sone inserter waits after
 144          * it has noticed a Sone modification before it starts the insert.
 145          *
 146          * @param insertionDelay
 147          *            The insertion delay (in seconds)
 148          */
 149         public static void setInsertionDelay(int insertionDelay) {
 150                 SoneInserter.insertionDelay = insertionDelay;
 151         }
 152
 153         /**
 154          * Returns the fingerprint of the last insert.
 155          *
 156          * @return The fingerprint of the last insert
 157          */
 158         public String getLastInsertFingerprint() {
 159                 return lastInsertFingerprint;
 160         }
 161
 162         /**
 163          * Sets the fingerprint of the last insert.
 164          *
 165          * @param lastInsertFingerprint
 166          *            The fingerprint of the last insert
 167          */
 168         public void setLastInsertFingerprint(String lastInsertFingerprint) {
 169                 this.lastInsertFingerprint = lastInsertFingerprint;
 170         }
 171
 172         /**
 173          * Returns whether the Sone inserter has detected a modification of the
 174          * Sone.
 175          *
 176          * @return {@code true} if the Sone has been modified, {@code false}
 177          *         otherwise
 178          */
 179         public boolean isModified() {
 180                 return modified;
 181         }
 182
 183         //
 184         // SERVICE METHODS
 185         //
 186
 187         /**
 188          * {@inheritDoc}
 189          */
 190         @Override
 191         protected void serviceRun() {
 192                 long lastModificationTime = 0;
 193                 String lastFingerprint = "";
 194                 while (!shouldStop()) { try {
 195                         /* check every seconds. */
 196                         sleep(1000);
 197
 198                         /* don’t insert locked Sones. */
 199                         if (core.isLocked(sone)) {
 200                                 /* trigger redetection when the Sone is unlocked. */
 201                                 synchronized (sone) {
 202                                         modified = !sone.getFingerprint().equals(lastInsertFingerprint);
 203                                 }
 204                                 lastFingerprint = "";
 205                                 lastModificationTime = 0;
 206                                 continue;
 207                         }
 208
 209                         InsertInformation insertInformation = null;
 210                         synchronized (sone) {
 211                                 String fingerprint = sone.getFingerprint();
 212                                 if (!fingerprint.equals(lastFingerprint)) {
 213                                         if (fingerprint.equals(lastInsertFingerprint)) {
 214                                                 modified = false;
 215                                                 lastModificationTime = 0;
 216                                                 logger.log(Level.FINE, "Sone %s has been reverted to last insert state.", sone);
 217                                         } else {
 218                                                 lastModificationTime = System.currentTimeMillis();
 219                                                 modified = true;
 220                                                 logger.log(Level.FINE, "Sone %s has been modified, waiting %d seconds before inserting.", new Object[] { sone.getName(), insertionDelay });
 221                                         }
 222                                         lastFingerprint = fingerprint;
 223                                 }
 224                                 if (modified && (lastModificationTime > 0) && ((System.currentTimeMillis() - lastModificationTime) > (insertionDelay * 1000))) {
 225                                         lastInsertFingerprint = fingerprint;
 226                                         insertInformation = new InsertInformation(sone);
 227                                 }
 228                         }
 229
 230                         if (insertInformation != null) {
 231                                 logger.log(Level.INFO, "Inserting Sone “%s”…", new Object[] { sone.getName() });
 232
 233                                 boolean success = false;
 234                                 try {
 235                                         core.setSoneStatus(sone, SoneStatus.inserting);
 236                                         long insertTime = System.currentTimeMillis();
 237                                         insertInformation.setTime(insertTime);
 238                                         soneInsertListenerManager.fireInsertStarted();
 239                                         FreenetURI finalUri = freenetInterface.insertDirectory(insertInformation.getInsertUri(), insertInformation.generateManifestEntries(), "index.html");
 240                                         soneInsertListenerManager.fireInsertFinished(System.currentTimeMillis() - insertTime);
 241                                         /* at this point we might already be stopped. */
 242                                         if (shouldStop()) {
 243                                                 /* if so, bail out, don’t change anything. */
 244                                                 break;
 245                                         }
 246                                         sone.setTime(insertTime);
 247                                         sone.setLatestEdition(finalUri.getEdition());
 248                                         core.touchConfiguration();
 249                                         success = true;
 250                                         logger.log(Level.INFO, "Inserted Sone “%s” at %s.", new Object[] { sone.getName(), finalUri });
 251                                 } catch (SoneException se1) {
 252                                         soneInsertListenerManager.fireInsertAborted(se1);
 253                                         logger.log(Level.WARNING, "Could not insert Sone “" + sone.getName() + "”!", se1);
 254                                 } finally {
 255                                         core.setSoneStatus(sone, SoneStatus.idle);
 256                                 }
 257
 258                                 /*
 259                                  * reset modification counter if Sone has not been modified
 260                                  * while it was inserted.
 261                                  */
 262                                 if (success) {
 263                                         synchronized (sone) {
 264                                                 if (lastInsertFingerprint.equals(sone.getFingerprint())) {
 265                                                         logger.log(Level.FINE, "Sone “%s” was not modified further, resetting counter…", new Object[] { sone });
 266                                                         lastModificationTime = 0;
 267                                                         modified = false;
 268                                                 }
 269                                         }
 270                                 }
 271                         }
 272                 } catch (Throwable t1) {
 273                         logger.log(Level.SEVERE, "SoneInserter threw an Exception!", t1);
 274                 }}
 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          * @author <a href="mailto:bombe@pterodactylus.net">David ‘Bombe’ Roden</a>
 283          */
 284         private class InsertInformation {
 285
 286                 /** All properties of the Sone, copied for thread safety. */
 287                 private final Map<String, Object> soneProperties = new HashMap<String, Object>();
 288
 289                 /**
 290                  * Creates a new insert information container.
 291                  *
 292                  * @param sone
 293                  *            The sone to insert
 294                  */
 295                 public InsertInformation(Sone sone) {
 296                         soneProperties.put("id", sone.getId());
 297                         soneProperties.put("name", sone.getName());
 298                         soneProperties.put("time", sone.getTime());
 299                         soneProperties.put("requestUri", sone.getRequestUri());
 300                         soneProperties.put("insertUri", sone.getInsertUri());
 301                         soneProperties.put("profile", sone.getProfile());
 302                         soneProperties.put("posts", new ListBuilder<Post>(new ArrayList<Post>(sone.getPosts())).sort(Post.TIME_COMPARATOR).get());
 303                         soneProperties.put("replies", new ListBuilder<PostReply>(new ArrayList<PostReply>(sone.getReplies())).sort(new ReverseComparator<Reply<?>>(Reply.TIME_COMPARATOR)).get());
 304                         soneProperties.put("likedPostIds", new HashSet<String>(sone.getLikedPostIds()));
 305                         soneProperties.put("likedReplyIds", new HashSet<String>(sone.getLikedReplyIds()));
 306                         soneProperties.put("albums", sone.getAllAlbums());
 307                 }
 308
 309                 //
 310                 // ACCESSORS
 311                 //
 312
 313                 /**
 314                  * Returns the insert URI of the Sone.
 315                  *
 316                  * @return The insert URI of the Sone
 317                  */
 318                 public FreenetURI getInsertUri() {
 319                         return (FreenetURI) soneProperties.get("insertUri");
 320                 }
 321
 322                 /**
 323                  * Sets the time of the Sone at the time of the insert.
 324                  *
 325                  * @param time
 326                  *            The time of the Sone
 327                  */
 328                 public void setTime(long time) {
 329                         soneProperties.put("time", time);
 330                 }
 331
 332                 //
 333                 // ACTIONS
 334                 //
 335
 336                 /**
 337                  * Generates all manifest entries required to insert this Sone.
 338                  *
 339                  * @return The manifest entries for the Sone insert
 340                  */
 341                 public HashMap<String, Object> generateManifestEntries() {
 342                         HashMap<String, Object> manifestEntries = new HashMap<String, Object>();
 343
 344                         /* first, create an index.html. */
 345                         manifestEntries.put("index.html", createManifestElement("index.html", "text/html; charset=utf-8", "/templates/insert/index.html"));
 346
 347                         /* now, store the sone. */
 348                         manifestEntries.put("sone.xml", createManifestElement("sone.xml", "text/xml; charset=utf-8", "/templates/insert/sone.xml"));
 349
 350                         return manifestEntries;
 351                 }
 352
 353                 //
 354                 // PRIVATE METHODS
 355                 //
 356
 357                 /**
 358                  * Creates a new manifest element.
 359                  *
 360                  * @param name
 361                  *            The name of the file
 362                  * @param contentType
 363                  *            The content type of the file
 364                  * @param templateName
 365                  *            The name of the template to render
 366                  * @return The manifest element
 367                  */
 368                 @SuppressWarnings("synthetic-access")
 369                 private ManifestElement createManifestElement(String name, String contentType, String templateName) {
 370                         InputStreamReader templateInputStreamReader = null;
 371                         Template template;
 372                         try {
 373                                 templateInputStreamReader = new InputStreamReader(getClass().getResourceAsStream(templateName), utf8Charset);
 374                                 template = TemplateParser.parse(templateInputStreamReader);
 375                         } catch (TemplateException te1) {
 376                                 logger.log(Level.SEVERE, "Could not parse template “" + templateName + "”!", te1);
 377                                 return null;
 378                         } finally {
 379                                 Closer.close(templateInputStreamReader);
 380                         }
 381
 382                         TemplateContext templateContext = templateContextFactory.createTemplateContext();
 383                         templateContext.set("core", core);
 384                         templateContext.set("currentSone", soneProperties);
 385                         templateContext.set("currentEdition", core.getUpdateChecker().getLatestEdition());
 386                         templateContext.set("version", SonePlugin.VERSION);
 387                         StringWriter writer = new StringWriter();
 388                         StringBucket bucket = null;
 389                         try {
 390                                 template.render(templateContext, writer);
 391                                 bucket = new StringBucket(writer.toString(), utf8Charset);
 392                                 return new ManifestElement(name, bucket, contentType, bucket.size());
 393                         } catch (TemplateException te1) {
 394                                 logger.log(Level.SEVERE, "Could not render template “" + templateName + "”!", te1);
 395                                 return null;
 396                         } finally {
 397                                 Closer.close(writer);
 398                                 if (bucket != null) {
 399                                         bucket.free();
 400                                 }
 401                         }
 402                 }
 403
 404         }
 405
 406 }