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

   1 /*
   2  * FreenetSone - 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.Reply;
  33 import net.pterodactylus.sone.data.Sone;
  34 import net.pterodactylus.sone.freenet.StringBucket;
  35 import net.pterodactylus.util.io.Closer;
  36 import net.pterodactylus.util.logging.Logging;
  37 import net.pterodactylus.util.service.AbstractService;
  38 import net.pterodactylus.util.template.DefaultTemplateFactory;
  39 import net.pterodactylus.util.template.ReflectionAccessor;
  40 import net.pterodactylus.util.template.Template;
  41 import net.pterodactylus.util.template.TemplateException;
  42 import net.pterodactylus.util.template.XmlFilter;
  43 import freenet.client.async.ManifestElement;
  44 import freenet.keys.FreenetURI;
  45
  46 /**
  47  * A Sone inserter is responsible for inserting a Sone if it has changed.
  48  *
  49  * @author <a href="mailto:bombe@pterodactylus.net">David ‘Bombe’ Roden</a>
  50  */
  51 public class SoneInserter extends AbstractService {
  52
  53         /** The logger. */
  54         private static final Logger logger = Logging.getLogger(SoneInserter.class);
  55
  56         /** The insertion delay (in seconds). */
  57         private static volatile int insertionDelay = 60;
  58
  59         /** The template factory used to create the templates. */
  60         private static final DefaultTemplateFactory templateFactory = new DefaultTemplateFactory();
  61
  62         static {
  63                 templateFactory.addAccessor(Object.class, new ReflectionAccessor());
  64                 templateFactory.addFilter("xml", new XmlFilter());
  65         }
  66
  67         /** The UTF-8 charset. */
  68         private static final Charset utf8Charset = Charset.forName("UTF-8");
  69
  70         /** The core. */
  71         private final Core core;
  72
  73         /** The Freenet interface. */
  74         private final FreenetInterface freenetInterface;
  75
  76         /** The Sone to insert. */
  77         private final Sone sone;
  78
  79         /**
  80          * Creates a new Sone inserter.
  81          *
  82          * @param core
  83          *            The core
  84          * @param freenetInterface
  85          *            The freenet interface
  86          * @param sone
  87          *            The Sone to insert
  88          */
  89         public SoneInserter(Core core, FreenetInterface freenetInterface, Sone sone) {
  90                 super("Sone Inserter for “" + sone.getName() + "”", false);
  91                 this.core = core;
  92                 this.freenetInterface = freenetInterface;
  93                 this.sone = sone;
  94         }
  95
  96         //
  97         // ACCESSORS
  98         //
  99
 100         /**
 101          * Changes the insertion delay, i.e. the time the Sone inserter waits after
 102          * it has noticed a Sone modification before it starts the insert.
 103          *
 104          * @param insertionDelay
 105          *            The insertion delay (in seconds)
 106          */
 107         public static void setInsertionDelay(int insertionDelay) {
 108                 SoneInserter.insertionDelay = insertionDelay;
 109         }
 110
 111         //
 112         // SERVICE METHODS
 113         //
 114
 115         /**
 116          * {@inheritDoc}
 117          */
 118         @Override
 119         protected void serviceRun() {
 120                 long modificationCounter = 0;
 121                 long lastModificationTime = 0;
 122                 while (!shouldStop()) {
 123                         /* check every seconds. */
 124                         sleep(1000);
 125
 126                         InsertInformation insertInformation = null;
 127                         synchronized (sone) {
 128                                 if (sone.getModificationCounter() > modificationCounter) {
 129                                         modificationCounter = sone.getModificationCounter();
 130                                         lastModificationTime = System.currentTimeMillis();
 131                                         sone.setTime(lastModificationTime);
 132                                         logger.log(Level.FINE, "Sone %s has been modified, waiting %d seconds before inserting.", new Object[] { sone.getName(), insertionDelay });
 133                                 }
 134                                 if ((lastModificationTime > 0) && ((System.currentTimeMillis() - lastModificationTime) > (insertionDelay * 1000))) {
 135                                         insertInformation = new InsertInformation(sone);
 136                                 }
 137                         }
 138
 139                         if (insertInformation != null) {
 140                                 logger.log(Level.INFO, "Inserting Sone “%s”…", new Object[] { sone.getName() });
 141
 142                                 boolean success = false;
 143                                 try {
 144                                         core.setSoneStatus(sone, SoneStatus.inserting);
 145                                         FreenetURI finalUri = freenetInterface.insertDirectory(insertInformation.getInsertUri().setKeyType("USK").setSuggestedEdition(0), insertInformation.generateManifestEntries(), "index.html");
 146                                         /* at this point we might already be stopped. */
 147                                         if (shouldStop()) {
 148                                                 /* if so, bail out, don’t change anything. */
 149                                                 break;
 150                                         }
 151                                         sone.setLatestEdition(finalUri.getEdition());
 152                                         success = true;
 153                                         logger.log(Level.INFO, "Inserted Sone “%s” at %s.", new Object[] { sone.getName(), finalUri });
 154                                 } catch (SoneException se1) {
 155                                         logger.log(Level.WARNING, "Could not insert Sone “" + sone.getName() + "”!", se1);
 156                                 } finally {
 157                                         core.setSoneStatus(sone, SoneStatus.idle);
 158                                 }
 159
 160                                 /*
 161                                  * reset modification counter if Sone has not been modified
 162                                  * while it was inserted.
 163                                  */
 164                                 if (success) {
 165                                         synchronized (sone) {
 166                                                 if (sone.getModificationCounter() == modificationCounter) {
 167                                                         logger.log(Level.FINE, "Sone “%s” was not modified further, resetting counter…", new Object[] { sone });
 168                                                         sone.setModificationCounter(0);
 169                                                         core.saveSone(sone);
 170                                                         modificationCounter = 0;
 171                                                         lastModificationTime = 0;
 172                                                 }
 173                                         }
 174                                 }
 175                         }
 176                 }
 177         }
 178
 179         /**
 180          * Container for information that are required to insert a Sone. This
 181          * container merely exists to copy all relevant data without holding a lock
 182          * on the {@link Sone} object for too long.
 183          *
 184          * @author <a href="mailto:bombe@pterodactylus.net">David ‘Bombe’ Roden</a>
 185          */
 186         private class InsertInformation {
 187
 188                 /** All properties of the Sone, copied for thread safety. */
 189                 private final Map<String, Object> soneProperties = new HashMap<String, Object>();
 190
 191                 /**
 192                  * Creates a new insert information container.
 193                  *
 194                  * @param sone
 195                  *            The sone to insert
 196                  */
 197                 public InsertInformation(Sone sone) {
 198                         soneProperties.put("id", sone.getId());
 199                         soneProperties.put("name", sone.getName());
 200                         soneProperties.put("time", sone.getTime());
 201                         soneProperties.put("requestUri", sone.getRequestUri());
 202                         soneProperties.put("insertUri", sone.getInsertUri());
 203                         soneProperties.put("profile", sone.getProfile());
 204                         soneProperties.put("posts", new ArrayList<Post>(sone.getPosts()));
 205                         soneProperties.put("replies", new HashSet<Reply>(sone.getReplies()));
 206                         soneProperties.put("likedPostIds", new HashSet<String>(sone.getLikedPostIds()));
 207                         soneProperties.put("likeReplyIds", new HashSet<String>(sone.getLikedReplyIds()));
 208                 }
 209
 210                 //
 211                 // ACCESSORS
 212                 //
 213
 214                 /**
 215                  * Returns the insert URI of the Sone.
 216                  *
 217                  * @return The insert URI of the Sone
 218                  */
 219                 public FreenetURI getInsertUri() {
 220                         return (FreenetURI) soneProperties.get("insertUri");
 221                 }
 222
 223                 //
 224                 // ACTIONS
 225                 //
 226
 227                 /**
 228                  * Generates all manifest entries required to insert this Sone.
 229                  *
 230                  * @return The manifest entries for the Sone insert
 231                  */
 232                 public HashMap<String, Object> generateManifestEntries() {
 233                         HashMap<String, Object> manifestEntries = new HashMap<String, Object>();
 234
 235                         /* first, create an index.html. */
 236                         manifestEntries.put("index.html", createManifestElement("index.html", "text/html; charset=utf-8", "/templates/insert/index.html"));
 237
 238                         /* now, store the sone. */
 239                         manifestEntries.put("sone.xml", createManifestElement("sone.xml", "text/xml; charset=utf-8", "/templates/insert/sone.xml"));
 240
 241                         return manifestEntries;
 242                 }
 243
 244                 //
 245                 // PRIVATE METHODS
 246                 //
 247
 248                 /**
 249                  * Creates a new manifest element.
 250                  *
 251                  * @param name
 252                  *            The name of the file
 253                  * @param contentType
 254                  *            The content type of the file
 255                  * @param templateName
 256                  *            The name of the template to render
 257                  * @return The manifest element
 258                  */
 259                 @SuppressWarnings("synthetic-access")
 260                 private ManifestElement createManifestElement(String name, String contentType, String templateName) {
 261                         InputStreamReader templateInputStreamReader;
 262                         Template template = templateFactory.createTemplate(templateInputStreamReader = new InputStreamReader(getClass().getResourceAsStream(templateName), utf8Charset));
 263                         try {
 264                                 template.parse();
 265                         } catch (TemplateException te1) {
 266                                 logger.log(Level.SEVERE, "Could not parse template “" + templateName + "”!", te1);
 267                                 return null;
 268                         } finally {
 269                                 Closer.close(templateInputStreamReader);
 270                         }
 271
 272                         template.set("currentSone", soneProperties);
 273                         StringWriter writer = new StringWriter();
 274                         StringBucket bucket = null;
 275                         try {
 276                                 template.render(writer);
 277                                 bucket = new StringBucket(writer.toString(), utf8Charset);
 278                                 return new ManifestElement(name, bucket, contentType, bucket.size());
 279                         } catch (TemplateException te1) {
 280                                 logger.log(Level.SEVERE, "Could not render template “" + templateName + "”!", te1);
 281                                 return null;
 282                         } finally {
 283                                 Closer.close(writer);
 284                                 if (bucket != null) {
 285                                         bucket.free();
 286                                 }
 287                         }
 288                 }
 289
 290         }
 291
 292 }