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.util.HashSet;
  23 import java.util.Set;
  24 import java.util.logging.Level;
  25 import java.util.logging.Logger;
  26
  27 import net.pterodactylus.sone.data.Post;
  28 import net.pterodactylus.sone.data.Profile;
  29 import net.pterodactylus.sone.data.Reply;
  30 import net.pterodactylus.sone.data.Sone;
  31 import net.pterodactylus.util.io.Closer;
  32 import net.pterodactylus.util.logging.Logging;
  33 import net.pterodactylus.util.service.AbstractService;
  34 import net.pterodactylus.util.xml.SimpleXML;
  35 import net.pterodactylus.util.xml.XML;
  36
  37 import org.w3c.dom.Document;
  38
  39 import freenet.client.FetchResult;
  40 import freenet.support.api.Bucket;
  41
  42 /**
  43  * The Sone downloader is responsible for download Sones as they are updated.
  44  *
  45  * @author <a href="mailto:bombe@pterodactylus.net">David ‘Bombe’ Roden</a>
  46  */
  47 public class SoneDownloader extends AbstractService {
  48
  49         /** The logger. */
  50         private static final Logger logger = Logging.getLogger(SoneDownloader.class);
  51
  52         /** The Freenet interface. */
  53         private final FreenetInterface freenetInterface;
  54
  55         /** The sones to update. */
  56         private final Set<Sone> sones = new HashSet<Sone>();
  57
  58         /**
  59          * Creates a new Sone downloader.
  60          *
  61          * @param freenetInterface
  62          *            The Freenet interface
  63          */
  64         public SoneDownloader(FreenetInterface freenetInterface) {
  65                 super("Sone Downloader");
  66                 this.freenetInterface = freenetInterface;
  67         }
  68
  69         //
  70         // ACTIONS
  71         //
  72
  73         /**
  74          * Adds the given Sone to the set of Sones that will be watched for updates.
  75          *
  76          * @param sone
  77          *            The Sone to add
  78          */
  79         public void addSone(Sone sone) {
  80                 if (sones.add(sone)) {
  81                         freenetInterface.registerUsk(sone, this);
  82                 }
  83         }
  84
  85         /**
  86          * Fetches the updated Sone. This method is a callback method for
  87          * {@link FreenetInterface#registerUsk(Sone, SoneDownloader)}.
  88          *
  89          * @param sone
  90          *            The Sone to fetch
  91          */
  92         public void fetchSone(Sone sone) {
  93                 logger.log(Level.FINE, "Starting fetch for Sone “%s” from %s…", new Object[] { sone, sone.getRequestUri().setMetaString(new String[] { "sone.xml" }) });
  94                 FetchResult fetchResult = freenetInterface.fetchUri(sone.getRequestUri().setMetaString(new String[] { "sone.xml" }));
  95                 logger.log(Level.FINEST, "Got %d bytes back.", fetchResult.size());
  96                 updateSoneFromXml(sone, fetchResult);
  97         }
  98
  99         //
 100         // SERVICE METHODS
 101         //
 102
 103         /**
 104          * {@inheritDoc}
 105          */
 106         @Override
 107         protected void serviceStop() {
 108                 for (Sone sone : sones) {
 109                         freenetInterface.unregisterUsk(sone);
 110                 }
 111         }
 112
 113         //
 114         // PRIVATE METHODS
 115         //
 116
 117         /**
 118          * Updates the contents of the given Sone from the given fetch result.
 119          *
 120          * @param sone
 121          *            The Sone to update
 122          * @param fetchResult
 123          *            The fetch result
 124          */
 125         private void updateSoneFromXml(Sone sone, FetchResult fetchResult) {
 126                 logger.log(Level.FINEST, "Persing FetchResult (%d bytes, %s) for %s…", new Object[] { fetchResult.size(), fetchResult.getMimeType(), sone });
 127                 /* TODO - impose a size limit? */
 128                 InputStream xmlInputStream = null;
 129                 Bucket xmlBucket = null;
 130                 try {
 131                         xmlBucket = fetchResult.asBucket();
 132                         xmlInputStream = xmlBucket.getInputStream();
 133                         Document document = XML.transformToDocument(xmlInputStream);
 134                         SimpleXML soneXml = SimpleXML.fromDocument(document);
 135
 136                         /* check ID. */
 137                         String soneId = soneXml.getValue("id", null);
 138                         if (!sone.getId().equals(soneId)) {
 139                                 /* TODO - mark Sone as bad. */
 140                                 logger.log(Level.WARNING, "Downloaded ID for Sone %s (%s) does not match known ID (%s)!", new Object[] { sone, sone.getId(), soneId });
 141                                 return;
 142                         }
 143
 144                         String soneName = soneXml.getValue("name", null);
 145                         if (soneName == null) {
 146                                 /* TODO - mark Sone as bad. */
 147                                 logger.log(Level.WARNING, "Downloaded name for Sone %s was null!", new Object[] { sone });
 148                                 return;
 149                         }
 150
 151                         SimpleXML profileXml = soneXml.getNode("profile");
 152                         if (profileXml == null) {
 153                                 /* TODO - mark Sone as bad. */
 154                                 logger.log(Level.WARNING, "Downloaded Sone %s has no profile!", new Object[] { sone });
 155                                 return;
 156                         }
 157
 158                         /* parse profile. */
 159                         String profileFirstName = profileXml.getValue("first-name", null);
 160                         String profileMiddleName = profileXml.getValue("middle-name", null);
 161                         String profileLastName = profileXml.getValue("last-name", null);
 162                         Profile profile = new Profile().setFirstName(profileFirstName).setMiddleName(profileMiddleName).setLastName(profileLastName);
 163
 164                         /* parse posts. */
 165                         SimpleXML postsXml = soneXml.getNode("posts");
 166                         if (postsXml == null) {
 167                                 /* TODO - mark Sone as bad. */
 168                                 logger.log(Level.WARNING, "Downloaded Sone %s has no posts!", new Object[] { sone });
 169                                 return;
 170                         }
 171
 172                         Set<Post> posts = new HashSet<Post>();
 173                         for (SimpleXML postXml : postsXml.getNodes("post")) {
 174                                 String postId = postXml.getValue("id", null);
 175                                 String postTime = postXml.getValue("time", null);
 176                                 String postText = postXml.getValue("text", null);
 177                                 if ((postId == null) || (postTime == null) || (postText == null)) {
 178                                         /* TODO - mark Sone as bad. */
 179                                         logger.log(Level.WARNING, "Downloaded post for Sone %s with missing data! ID: %s, Time: %s, Text: %s", new Object[] { sone, postId, postTime, postText });
 180                                         return;
 181                                 }
 182                                 try {
 183                                         posts.add(new Post(postId, sone, Long.parseLong(postTime), postText));
 184                                 } catch (NumberFormatException nfe1) {
 185                                         /* TODO - mark Sone as bad. */
 186                                         logger.log(Level.WARNING, "Downloaded post for Sone %s with invalid time: %s", new Object[] { sone, postTime });
 187                                         return;
 188                                 }
 189                         }
 190
 191                         /* parse replies. */
 192                         SimpleXML repliesXml = soneXml.getNode("replies");
 193                         if (repliesXml == null) {
 194                                 /* TODO - mark Sone as bad. */
 195                                 logger.log(Level.WARNING, "Downloaded Sone %s has no replies!", new Object[] { sone });
 196                                 return;
 197                         }
 198
 199                         Set<Reply> replies = new HashSet<Reply>();
 200                         for (SimpleXML replyXml : repliesXml.getNodes("reply")) {
 201                                 String replyId = replyXml.getValue("id", null);
 202                                 String replyPostId = replyXml.getValue("post-id", null);
 203                                 String replyTime = replyXml.getValue("time", null);
 204                                 String replyText = replyXml.getValue("text", null);
 205                                 /* TODO - finish! */
 206                         }
 207                 } catch (IOException ioe1) {
 208                         logger.log(Level.WARNING, "Could not read XML file from " + sone + "!", ioe1);
 209                 } finally {
 210                         if (xmlBucket != null) {
 211                                 xmlBucket.free();
 212                         }
 213                         Closer.close(xmlInputStream);
 214                 }
 215         }
 216
 217 }