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

   1 /*
   2  * Sone - SoneDownloader.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.IOException;
  21 import java.io.InputStream;
  22 import java.net.MalformedURLException;
  23 import java.util.HashSet;
  24 import java.util.Set;
  25 import java.util.logging.Level;
  26 import java.util.logging.Logger;
  27
  28 import net.pterodactylus.sone.core.Core.SoneStatus;
  29 import net.pterodactylus.sone.data.Post;
  30 import net.pterodactylus.sone.data.Profile;
  31 import net.pterodactylus.sone.data.Reply;
  32 import net.pterodactylus.sone.data.Sone;
  33 import net.pterodactylus.util.io.Closer;
  34 import net.pterodactylus.util.logging.Logging;
  35 import net.pterodactylus.util.service.AbstractService;
  36 import net.pterodactylus.util.xml.SimpleXML;
  37 import net.pterodactylus.util.xml.XML;
  38
  39 import org.w3c.dom.Document;
  40
  41 import freenet.client.FetchResult;
  42 import freenet.keys.FreenetURI;
  43 import freenet.support.api.Bucket;
  44
  45 /**
  46  * The Sone downloader is responsible for download Sones as they are updated.
  47  *
  48  * @author <a href="mailto:bombe@pterodactylus.net">David ‘Bombe’ Roden</a>
  49  */
  50 public class SoneDownloader extends AbstractService {
  51
  52         /** The logger. */
  53         private static final Logger logger = Logging.getLogger(SoneDownloader.class);
  54
  55         /** The core. */
  56         private final Core core;
  57
  58         /** The Freenet interface. */
  59         private final FreenetInterface freenetInterface;
  60
  61         /** The sones to update. */
  62         private final Set<Sone> sones = new HashSet<Sone>();
  63
  64         /**
  65          * Creates a new Sone downloader.
  66          *
  67          * @param core
  68          *            The core
  69          * @param freenetInterface
  70          *            The Freenet interface
  71          */
  72         public SoneDownloader(Core core, FreenetInterface freenetInterface) {
  73                 super("Sone Downloader", false);
  74                 this.core = core;
  75                 this.freenetInterface = freenetInterface;
  76         }
  77
  78         //
  79         // ACTIONS
  80         //
  81
  82         /**
  83          * Adds the given Sone to the set of Sones that will be watched for updates.
  84          *
  85          * @param sone
  86          *            The Sone to add
  87          */
  88         public void addSone(Sone sone) {
  89                 if (sones.add(sone)) {
  90                         freenetInterface.registerUsk(sone, this);
  91                 }
  92         }
  93
  94         /**
  95          * Removes the given Sone from the downloader.
  96          *
  97          * @param sone
  98          *            The Sone to stop watching
  99          */
 100         public void removeSone(Sone sone) {
 101                 if (sones.remove(sone)) {
 102                         freenetInterface.unregisterUsk(sone);
 103                 }
 104         }
 105
 106         /**
 107          * Fetches the updated Sone. This method is a callback method for
 108          * {@link FreenetInterface#registerUsk(Sone, SoneDownloader)}.
 109          *
 110          * @param sone
 111          *            The Sone to fetch
 112          */
 113         public void fetchSone(Sone sone) {
 114                 logger.log(Level.FINE, "Starting fetch for Sone “%s” from %s…", new Object[] { sone, sone.getRequestUri().setMetaString(new String[] { "sone.xml" }) });
 115                 FreenetURI requestUri = sone.getRequestUri().setMetaString(new String[] { "sone.xml" });
 116                 core.setSoneStatus(sone, SoneStatus.downloading);
 117                 try {
 118                         FetchResult fetchResult = freenetInterface.fetchUri(requestUri);
 119                         if (fetchResult == null) {
 120                                 /* TODO - mark Sone as bad. */
 121                                 return;
 122                         }
 123                         logger.log(Level.FINEST, "Got %d bytes back.", fetchResult.size());
 124                         Sone parsedSone = parseSone(sone, fetchResult, requestUri);
 125                         if (parsedSone != null) {
 126                                 core.addSone(parsedSone);
 127                         }
 128                 } finally {
 129                         core.setSoneStatus(sone, (sone.getTime() == 0) ? SoneStatus.unknown : SoneStatus.idle);
 130                 }
 131         }
 132
 133         /**
 134          * Parses a Sone from a fetch result.
 135          *
 136          * @param originalSone
 137          *            The sone to parse, or {@code null} if the Sone is yet unknown
 138          * @param fetchResult
 139          *            The fetch result
 140          * @param requestUri
 141          *            The requested URI
 142          * @return The parsed Sone, or {@code null} if the Sone could not be parsed
 143          */
 144         public Sone parseSone(Sone originalSone, FetchResult fetchResult, FreenetURI requestUri) {
 145                 logger.log(Level.FINEST, "Persing FetchResult (%d bytes, %s) for %s…", new Object[] { fetchResult.size(), fetchResult.getMimeType(), originalSone });
 146                 /* TODO - impose a size limit? */
 147                 InputStream xmlInputStream = null;
 148                 Bucket xmlBucket = null;
 149                 Sone sone;
 150                 try {
 151                         xmlBucket = fetchResult.asBucket();
 152                         xmlInputStream = xmlBucket.getInputStream();
 153                         Document document;
 154                         /* XML parsing is not thread-safe. */
 155                         synchronized (this) {
 156                                 document = XML.transformToDocument(xmlInputStream);
 157                         }
 158                         if (document == null) {
 159                                 /* TODO - mark Sone as bad. */
 160                                 logger.log(Level.WARNING, "Could not parse XML for Sone %s at %s!", new Object[] { originalSone, requestUri });
 161                                 return null;
 162                         }
 163                         SimpleXML soneXml;
 164                         try {
 165                                 soneXml = SimpleXML.fromDocument(document);
 166                         } catch (NullPointerException npe1) {
 167                                 /* for some reason, invalid XML can cause NPEs. */
 168                                 logger.log(Level.WARNING, "XML for Sone " + originalSone + " can not be parsed!", npe1);
 169                                 return null;
 170                         }
 171
 172                         /* check ID. */
 173                         String soneId = soneXml.getValue("id", null);
 174                         if ((originalSone != null) && !originalSone.getId().equals(soneId)) {
 175                                 /* TODO - mark Sone as bad. */
 176                                 logger.log(Level.WARNING, "Downloaded ID for Sone %s (%s) does not match known ID (%s)!", new Object[] { originalSone, originalSone.getId(), soneId });
 177                                 return null;
 178                         }
 179
 180                         /* load Sone from core. */
 181                         sone = originalSone;
 182                         if (sone == null) {
 183                                 sone = core.getSone(soneId).setRequestUri(requestUri.setMetaString(new String[] {}));
 184                         }
 185
 186                         String soneName = soneXml.getValue("name", null);
 187                         if (soneName == null) {
 188                                 /* TODO - mark Sone as bad. */
 189                                 logger.log(Level.WARNING, "Downloaded name for Sone %s was null!", new Object[] { sone });
 190                                 return null;
 191                         }
 192                         sone.setName(soneName);
 193
 194                         String soneTime = soneXml.getValue("time", null);
 195                         if (soneTime == null) {
 196                                 /* TODO - mark Sone as bad. */
 197                                 logger.log(Level.WARNING, "Downloaded time for Sone %s was null!", new Object[] { sone });
 198                                 return null;
 199                         }
 200                         try {
 201                                 sone.setTime(Long.parseLong(soneTime));
 202                         } catch (NumberFormatException nfe1) {
 203                                 /* TODO - mark Sone as bad. */
 204                                 logger.log(Level.WARNING, "Downloaded Sone %s with invalid time: %s", new Object[] { sone, soneTime });
 205                                 return null;
 206                         }
 207
 208                         SimpleXML profileXml = soneXml.getNode("profile");
 209                         if (profileXml == null) {
 210                                 /* TODO - mark Sone as bad. */
 211                                 logger.log(Level.WARNING, "Downloaded Sone %s has no profile!", new Object[] { sone });
 212                                 return null;
 213                         }
 214
 215                         /* parse profile. */
 216                         String profileFirstName = profileXml.getValue("first-name", null);
 217                         String profileMiddleName = profileXml.getValue("middle-name", null);
 218                         String profileLastName = profileXml.getValue("last-name", null);
 219                         Profile profile = new Profile().setFirstName(profileFirstName).setMiddleName(profileMiddleName).setLastName(profileLastName);
 220
 221                         /* parse posts. */
 222                         SimpleXML postsXml = soneXml.getNode("posts");
 223                         if (postsXml == null) {
 224                                 /* TODO - mark Sone as bad. */
 225                                 logger.log(Level.WARNING, "Downloaded Sone %s has no posts!", new Object[] { sone });
 226                                 return null;
 227                         }
 228
 229                         Set<Post> posts = new HashSet<Post>();
 230                         for (SimpleXML postXml : postsXml.getNodes("post")) {
 231                                 String postId = postXml.getValue("id", null);
 232                                 String postTime = postXml.getValue("time", null);
 233                                 String postText = postXml.getValue("text", null);
 234                                 if ((postId == null) || (postTime == null) || (postText == null)) {
 235                                         /* TODO - mark Sone as bad. */
 236                                         logger.log(Level.WARNING, "Downloaded post for Sone %s with missing data! ID: %s, Time: %s, Text: %s", new Object[] { sone, postId, postTime, postText });
 237                                         return null;
 238                                 }
 239                                 try {
 240                                         posts.add(core.getPost(postId).setSone(sone).setTime(Long.parseLong(postTime)).setText(postText));
 241                                 } catch (NumberFormatException nfe1) {
 242                                         /* TODO - mark Sone as bad. */
 243                                         logger.log(Level.WARNING, "Downloaded post for Sone %s with invalid time: %s", new Object[] { sone, postTime });
 244                                         return null;
 245                                 }
 246                         }
 247
 248                         /* parse replies. */
 249                         SimpleXML repliesXml = soneXml.getNode("replies");
 250                         if (repliesXml == null) {
 251                                 /* TODO - mark Sone as bad. */
 252                                 logger.log(Level.WARNING, "Downloaded Sone %s has no replies!", new Object[] { sone });
 253                                 return null;
 254                         }
 255
 256                         Set<Reply> replies = new HashSet<Reply>();
 257                         for (SimpleXML replyXml : repliesXml.getNodes("reply")) {
 258                                 String replyId = replyXml.getValue("id", null);
 259                                 String replyPostId = replyXml.getValue("post-id", null);
 260                                 String replyTime = replyXml.getValue("time", null);
 261                                 String replyText = replyXml.getValue("text", null);
 262                                 if ((replyId == null) || (replyPostId == null) || (replyTime == null) || (replyText == null)) {
 263                                         /* TODO - mark Sone as bad. */
 264                                         logger.log(Level.WARNING, "Downloaded reply for Sone %s with missing data! ID: %s, Post: %s, Time: %s, Text: %s", new Object[] { sone, replyId, replyPostId, replyTime, replyText });
 265                                         return null;
 266                                 }
 267                                 try {
 268                                         replies.add(core.getReply(replyId).setSone(sone).setPost(core.getPost(replyPostId)).setTime(Long.parseLong(replyTime)).setText(replyText));
 269                                 } catch (NumberFormatException nfe1) {
 270                                         /* TODO - mark Sone as bad. */
 271                                         logger.log(Level.WARNING, "Downloaded reply for Sone %s with invalid time: %s", new Object[] { sone, replyTime });
 272                                         return null;
 273                                 }
 274                         }
 275
 276                         /* parse friends. */
 277                         SimpleXML friendsXml = soneXml.getNode("friends");
 278                         if (friendsXml == null) {
 279                                 /* TODO - mark Sone as bad. */
 280                                 logger.log(Level.WARNING, "Downloaded Sone %s has no friends!", new Object[] { sone });
 281                                 return null;
 282                         }
 283
 284                         Set<Sone> friends = new HashSet<Sone>();
 285                         for (SimpleXML friendXml : friendsXml.getNodes("friend")) {
 286                                 String friendId = friendXml.getValue("sone-id", null);
 287                                 String friendKey = friendXml.getValue("sone-key", null);
 288                                 String friendName = friendXml.getValue("sone-name", null);
 289                                 if ((friendId == null) || (friendKey == null) || (friendName == null)) {
 290                                         /* TODO - mark Sone as bad. */
 291                                         logger.log(Level.WARNING, "Downloaded friend for Sone %s with missing data! ID: %s, Key: %s, Name: %s", new Object[] { sone, friendId, friendKey, friendName });
 292                                         return null;
 293                                 }
 294                                 try {
 295                                         friends.add(core.getSone(friendId).setRequestUri(new FreenetURI(friendKey)).setName(friendName));
 296                                 } catch (MalformedURLException mue1) {
 297                                         /* TODO - mark Sone as bad. */
 298                                         logger.log(Level.WARNING, "Downloaded friend for Sone %s with invalid key: %s", new Object[] { sone, friendKey });
 299                                         return null;
 300                                 }
 301                         }
 302
 303                         Set<Sone> knownSones = new HashSet<Sone>();
 304                         for (SimpleXML friendXml : friendsXml.getNodes("friend")) {
 305                                 String knownSoneId = friendXml.getValue("sone-id", null);
 306                                 String knownSoneKey = friendXml.getValue("sone-key", null);
 307                                 String knownSoneName = friendXml.getValue("sone-name", null);
 308                                 if ((knownSoneId == null) || (knownSoneKey == null) || (knownSoneName == null)) {
 309                                         /* TODO - mark Sone as bad. */
 310                                         logger.log(Level.WARNING, "Downloaded known Sone for Sone %s with missing data! ID: %s, Key: %s, Name: %s", new Object[] { sone, knownSoneId, knownSoneKey, knownSoneName });
 311                                         return null;
 312                                 }
 313                                 try {
 314                                         knownSones.add(core.getSone(knownSoneId).setRequestUri(new FreenetURI(knownSoneKey)).setName(knownSoneName));
 315                                 } catch (MalformedURLException mue1) {
 316                                         /* TODO - mark Sone as bad. */
 317                                         logger.log(Level.WARNING, "Downloaded known Sone for Sone %s with invalid key: %s", new Object[] { sone, knownSoneKey });
 318                                         return null;
 319                                 }
 320                         }
 321
 322                         /* okay, apparently everything was parsed correctly. Now import. */
 323                         /* atomic setter operation on the Sone. */
 324                         synchronized (sone) {
 325                                 sone.setProfile(profile);
 326                                 sone.setPosts(posts);
 327                                 sone.setReplies(replies);
 328                                 sone.setFriends(friends);
 329                                 sone.setModificationCounter(0);
 330                         }
 331
 332                         /* add all known Sones to core for downloading. */
 333                         for (Sone knownSone : knownSones) {
 334                                 core.addSone(knownSone);
 335                         }
 336
 337                 } catch (IOException ioe1) {
 338                         logger.log(Level.WARNING, "Could not read XML file from " + originalSone + "!", ioe1);
 339                         return null;
 340                 } finally {
 341                         if (xmlBucket != null) {
 342                                 xmlBucket.free();
 343                         }
 344                         Closer.close(xmlInputStream);
 345                 }
 346                 return sone;
 347         }
 348
 349         //
 350         // SERVICE METHODS
 351         //
 352
 353         /**
 354          * {@inheritDoc}
 355          */
 356         @Override
 357         protected void serviceStop() {
 358                 for (Sone sone : sones) {
 359                         freenetInterface.unregisterUsk(sone);
 360                 }
 361         }
 362
 363 }