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