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

   1 /*
   2  * Sone - FreenetInterface.java - Copyright © 2010–2016 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 static freenet.keys.USK.create;
  21 import static java.lang.String.format;
  22 import static java.util.logging.Level.WARNING;
  23 import static java.util.logging.Logger.getLogger;
  24 import static net.pterodactylus.sone.freenet.Key.routingKey;
  25
  26 import java.io.IOException;
  27 import java.net.MalformedURLException;
  28 import java.util.Collections;
  29 import java.util.HashMap;
  30 import java.util.Map;
  31 import java.util.logging.Level;
  32 import java.util.logging.Logger;
  33
  34 import javax.annotation.Nonnull;
  35 import javax.inject.Inject;
  36
  37 import net.pterodactylus.sone.core.event.ImageInsertAbortedEvent;
  38 import net.pterodactylus.sone.core.event.ImageInsertFailedEvent;
  39 import net.pterodactylus.sone.core.event.ImageInsertFinishedEvent;
  40 import net.pterodactylus.sone.core.event.ImageInsertStartedEvent;
  41 import net.pterodactylus.sone.data.Image;
  42 import net.pterodactylus.sone.data.Sone;
  43 import net.pterodactylus.sone.data.TemporaryImage;
  44
  45 import com.google.common.base.Function;
  46 import com.google.common.eventbus.EventBus;
  47 import com.google.inject.Singleton;
  48
  49 import freenet.client.ClientMetadata;
  50 import freenet.client.FetchContext;
  51 import freenet.client.FetchException;
  52 import freenet.client.FetchException.FetchExceptionMode;
  53 import freenet.client.FetchResult;
  54 import freenet.client.HighLevelSimpleClient;
  55 import freenet.client.InsertBlock;
  56 import freenet.client.InsertContext;
  57 import freenet.client.InsertException;
  58 import freenet.client.Metadata;
  59 import freenet.client.async.BaseClientPutter;
  60 import freenet.client.async.ClientContext;
  61 import freenet.client.async.ClientGetCallback;
  62 import freenet.client.async.ClientGetter;
  63 import freenet.client.async.ClientPutCallback;
  64 import freenet.client.async.ClientPutter;
  65 import freenet.client.async.SnoopMetadata;
  66 import freenet.client.async.USKCallback;
  67 import freenet.keys.FreenetURI;
  68 import freenet.keys.InsertableClientSSK;
  69 import freenet.keys.USK;
  70 import freenet.node.Node;
  71 import freenet.node.RequestClient;
  72 import freenet.node.RequestClientBuilder;
  73 import freenet.node.RequestStarter;
  74 import freenet.support.api.Bucket;
  75 import freenet.support.api.RandomAccessBucket;
  76 import freenet.support.io.ArrayBucket;
  77 import freenet.support.io.ResumeFailedException;
  78
  79 /**
  80  * Contains all necessary functionality for interacting with the Freenet node.
  81  */
  82 @Singleton
  83 public class FreenetInterface {
  84
  85         /** The logger. */
  86         private static final Logger logger = getLogger(FreenetInterface.class.getName());
  87
  88         /** The event bus. */
  89         private final EventBus eventBus;
  90
  91         /** The node to interact with. */
  92         private final Node node;
  93
  94         /** The high-level client to use for requests. */
  95         private final HighLevelSimpleClient client;
  96         private final RequestClient requestClient = new RequestClientBuilder().realTime().build();
  97
  98         /** The USK callbacks. */
  99         private final Map<String, USKCallback> soneUskCallbacks = new HashMap<>();
 100
 101         /** The not-Sone-related USK callbacks. */
 102         private final Map<FreenetURI, USKCallback> uriUskCallbacks = Collections.synchronizedMap(new HashMap<FreenetURI, USKCallback>());
 103
 104         private final RequestClient imageInserts = new RequestClientBuilder().realTime().build();
 105         private final RequestClient imageLoader = new RequestClientBuilder().realTime().build();
 106
 107         /**
 108          * Creates a new Freenet interface.
 109          *
 110          * @param eventBus
 111          *            The event bus
 112          * @param node
 113          *            The node to interact with
 114          */
 115         @Inject
 116         public FreenetInterface(EventBus eventBus, Node node) {
 117                 this.eventBus = eventBus;
 118                 this.node = node;
 119                 this.client = node.clientCore.makeClient(RequestStarter.INTERACTIVE_PRIORITY_CLASS, false, true);
 120         }
 121
 122         //
 123         // ACTIONS
 124         //
 125
 126         /**
 127          * Fetches the given URI.
 128          *
 129          * @param uri
 130          *            The URI to fetch
 131          * @return The result of the fetch, or {@code null} if an error occured
 132          */
 133         public Fetched fetchUri(FreenetURI uri) {
 134                 FreenetURI currentUri = new FreenetURI(uri);
 135                 while (true) {
 136                         try {
 137                                 FetchResult fetchResult = client.fetch(currentUri);
 138                                 return new Fetched(currentUri, fetchResult);
 139                         } catch (FetchException fe1) {
 140                                 if (fe1.getMode() == FetchExceptionMode.PERMANENT_REDIRECT) {
 141                                         currentUri = fe1.newURI;
 142                                         continue;
 143                                 }
 144                                 logger.log(Level.WARNING, String.format("Could not fetch “%s”!", uri), fe1);
 145                                 return null;
 146                         }
 147                 }
 148         }
 149
 150         public void startFetch(final FreenetURI uri, final BackgroundFetchCallback backgroundFetchCallback) {
 151                 ClientGetCallback callback = new ClientGetCallback() {
 152                         @Override
 153                         public void onSuccess(FetchResult result, ClientGetter state) {
 154                                 try {
 155                                         backgroundFetchCallback.loaded(uri, result.getMimeType(), result.asByteArray());
 156                                 } catch (IOException e) {
 157                                         backgroundFetchCallback.failed(uri);
 158                                 }
 159                         }
 160
 161                         @Override
 162                         public void onFailure(FetchException e, ClientGetter state) {
 163                                 backgroundFetchCallback.failed(uri);
 164                         }
 165
 166                         @Override
 167                         public void onResume(ClientContext context) throws ResumeFailedException {
 168                                 /* do nothing. */
 169                         }
 170
 171                         @Override
 172                         public RequestClient getRequestClient() {
 173                                 return imageLoader;
 174                         }
 175                 };
 176                 SnoopMetadata snoop = new SnoopMetadata() {
 177                         @Override
 178                         public boolean snoopMetadata(Metadata meta, ClientContext context) {
 179                                 String mimeType = meta.getMIMEType();
 180                                 boolean cancel = (mimeType == null) || backgroundFetchCallback.shouldCancel(uri, mimeType, meta.dataLength());
 181                                 if (cancel) {
 182                                         backgroundFetchCallback.failed(uri);
 183                                 }
 184                                 return cancel;
 185                         }
 186                 };
 187                 FetchContext fetchContext = client.getFetchContext();
 188                 try {
 189                         ClientGetter clientGetter = client.fetch(uri, 2097152, callback, fetchContext, RequestStarter.INTERACTIVE_PRIORITY_CLASS);
 190                         clientGetter.setMetaSnoop(snoop);
 191                         clientGetter.restart(uri, fetchContext.filterData, node.clientCore.clientContext);
 192                 } catch (FetchException fe) {
 193                         /* stupid exception that can not actually be thrown! */
 194                 }
 195         }
 196
 197         public interface BackgroundFetchCallback {
 198                 boolean shouldCancel(@Nonnull FreenetURI uri, @Nonnull String mimeType, long size);
 199                 void loaded(@Nonnull FreenetURI uri, @Nonnull String mimeType, @Nonnull byte[] data);
 200                 void failed(@Nonnull FreenetURI uri);
 201         }
 202
 203         /**
 204          * Inserts the image data of the given {@link TemporaryImage} and returns
 205          * the given insert token that can be used to add listeners or cancel the
 206          * insert.
 207          *
 208          * @param temporaryImage
 209          *            The temporary image data
 210          * @param image
 211          *            The image
 212          * @param insertToken
 213          *            The insert token
 214          * @throws SoneException
 215          *             if the insert could not be started
 216          */
 217         public void insertImage(TemporaryImage temporaryImage, Image image, InsertToken insertToken) throws SoneException {
 218                 String filenameHint = image.getId() + "." + temporaryImage.getMimeType().substring(temporaryImage.getMimeType().lastIndexOf("/") + 1);
 219                 InsertableClientSSK key = InsertableClientSSK.createRandom(node.random, "");
 220                 FreenetURI targetUri = key.getInsertURI().setDocName(filenameHint);
 221                 InsertContext insertContext = client.getInsertContext(true);
 222                 RandomAccessBucket bucket = new ArrayBucket(temporaryImage.getImageData());
 223                 insertToken.setBucket(bucket);
 224                 ClientMetadata metadata = new ClientMetadata(temporaryImage.getMimeType());
 225                 InsertBlock insertBlock = new InsertBlock(bucket, metadata, targetUri);
 226                 try {
 227                         ClientPutter clientPutter = client.insert(insertBlock, null, false, insertContext, insertToken, RequestStarter.INTERACTIVE_PRIORITY_CLASS);
 228                         insertToken.setClientPutter(clientPutter);
 229                 } catch (InsertException ie1) {
 230                         throw new SoneInsertException("Could not start image insert.", ie1);
 231                 }
 232         }
 233
 234         /**
 235          * Inserts a directory into Freenet.
 236          *
 237          * @param insertUri
 238          *            The insert URI
 239          * @param manifestEntries
 240          *            The directory entries
 241          * @param defaultFile
 242          *            The name of the default file
 243          * @return The generated URI
 244          * @throws SoneException
 245          *             if an insert error occurs
 246          */
 247         public FreenetURI insertDirectory(FreenetURI insertUri, HashMap<String, Object> manifestEntries, String defaultFile) throws SoneException {
 248                 try {
 249                         return client.insertManifest(insertUri, manifestEntries, defaultFile);
 250                 } catch (InsertException ie1) {
 251                         throw new SoneException(ie1);
 252                 }
 253         }
 254
 255         public void registerActiveUsk(FreenetURI requestUri,
 256                         USKCallback uskCallback) {
 257                 try {
 258                         soneUskCallbacks.put(routingKey(requestUri), uskCallback);
 259                         node.clientCore.uskManager.subscribe(create(requestUri),
 260                                         uskCallback, true, requestClient);
 261                 } catch (MalformedURLException mue1) {
 262                         logger.log(WARNING, format("Could not subscribe USK “%s”!",
 263                                         requestUri), mue1);
 264                 }
 265         }
 266
 267         public void registerPassiveUsk(FreenetURI requestUri,
 268                         USKCallback uskCallback) {
 269                 try {
 270                         soneUskCallbacks.put(routingKey(requestUri), uskCallback);
 271                         node.clientCore
 272                                         .uskManager
 273                                         .subscribe(create(requestUri), uskCallback, false, requestClient);
 274                 } catch (MalformedURLException mue1) {
 275                         logger.log(WARNING,
 276                                         format("Could not subscribe USK “%s”!", requestUri),
 277                                         mue1);
 278                 }
 279         }
 280
 281         /**
 282          * Unsubscribes the request URI of the given Sone.
 283          *
 284          * @param sone
 285          *            The Sone to unregister
 286          */
 287         public void unregisterUsk(Sone sone) {
 288                 USKCallback uskCallback = soneUskCallbacks.remove(sone.getId());
 289                 if (uskCallback == null) {
 290                         return;
 291                 }
 292                 try {
 293                         logger.log(Level.FINEST, String.format("Unsubscribing from USK for %s…", sone));
 294                         node.clientCore.uskManager.unsubscribe(USK.create(sone.getRequestUri()), uskCallback);
 295                 } catch (MalformedURLException mue1) {
 296                         logger.log(Level.FINE, String.format("Could not unsubscribe USK “%s”!", sone.getRequestUri()), mue1);
 297                 }
 298         }
 299
 300         /**
 301          * Registers an arbitrary URI and calls the given callback if a new edition
 302          * is found.
 303          *
 304          * @param uri
 305          *            The URI to watch
 306          * @param callback
 307          *            The callback to call
 308          */
 309         public void registerUsk(FreenetURI uri, final Callback callback) {
 310                 USKCallback uskCallback = new USKCallback() {
 311
 312                         @Override
 313                         public void onFoundEdition(long edition, USK key, ClientContext clientContext, boolean metadata, short codec, byte[] data, boolean newKnownGood, boolean newSlotToo) {
 314                                 callback.editionFound(key.getURI(), edition, newKnownGood, newSlotToo);
 315                         }
 316
 317                         @Override
 318                         public short getPollingPriorityNormal() {
 319                                 return RequestStarter.PREFETCH_PRIORITY_CLASS;
 320                         }
 321
 322                         @Override
 323                         public short getPollingPriorityProgress() {
 324                                 return RequestStarter.INTERACTIVE_PRIORITY_CLASS;
 325                         }
 326
 327                 };
 328                 try {
 329                         node.clientCore.uskManager.subscribe(USK.create(uri), uskCallback, true, requestClient);
 330                         uriUskCallbacks.put(uri, uskCallback);
 331                 } catch (MalformedURLException mue1) {
 332                         logger.log(Level.WARNING, String.format("Could not subscribe to USK: %s", uri), mue1);
 333                 }
 334         }
 335
 336         /**
 337          * Unregisters the USK watcher for the given URI.
 338          *
 339          * @param uri
 340          *            The URI to unregister the USK watcher for
 341          */
 342         public void unregisterUsk(FreenetURI uri) {
 343                 USKCallback uskCallback = uriUskCallbacks.remove(uri);
 344                 if (uskCallback == null) {
 345                         logger.log(Level.INFO, String.format("Could not unregister unknown USK: %s", uri));
 346                         return;
 347                 }
 348                 try {
 349                         node.clientCore.uskManager.unsubscribe(USK.create(uri), uskCallback);
 350                 } catch (MalformedURLException mue1) {
 351                         logger.log(Level.INFO, String.format("Could not unregister invalid USK: %s", uri), mue1);
 352                 }
 353         }
 354
 355         /**
 356          * Callback for USK watcher events.
 357          */
 358         public static interface Callback {
 359
 360                 /**
 361                  * Notifies a listener that a new edition was found for a URI.
 362                  *
 363                  * @param uri
 364                  *            The URI that a new edition was found for
 365                  * @param edition
 366                  *            The found edition
 367                  * @param newKnownGood
 368                  *            Whether the found edition was actually fetched
 369                  * @param newSlot
 370                  *            Whether the found edition is higher than all previously
 371                  *            found editions
 372                  */
 373                 public void editionFound(FreenetURI uri, long edition, boolean newKnownGood, boolean newSlot);
 374
 375         }
 376
 377         /**
 378          * Insert token that can cancel a running insert and sends events.
 379          *
 380          * @see ImageInsertAbortedEvent
 381          * @see ImageInsertStartedEvent
 382          * @see ImageInsertFailedEvent
 383          * @see ImageInsertFinishedEvent
 384          */
 385         public class InsertToken implements ClientPutCallback {
 386
 387                 /** The image being inserted. */
 388                 private final Image image;
 389
 390                 /** The client putter. */
 391                 private ClientPutter clientPutter;
 392                 private Bucket bucket;
 393
 394                 /** The final URI. */
 395                 private volatile FreenetURI resultingUri;
 396
 397                 /**
 398                  * Creates a new insert token for the given image.
 399                  *
 400                  * @param image
 401                  *            The image being inserted
 402                  */
 403                 public InsertToken(Image image) {
 404                         this.image = image;
 405                 }
 406
 407                 //
 408                 // ACCESSORS
 409                 //
 410
 411                 /**
 412                  * Sets the client putter that is inserting the image. This will also
 413                  * signal all registered listeners that the image has started.
 414                  *
 415                  * @param clientPutter
 416                  *            The client putter
 417                  */
 418                 @SuppressWarnings("synthetic-access")
 419                 public void setClientPutter(ClientPutter clientPutter) {
 420                         this.clientPutter = clientPutter;
 421                         eventBus.post(new ImageInsertStartedEvent(image));
 422                 }
 423
 424                 public void setBucket(Bucket bucket) {
 425                         this.bucket = bucket;
 426                 }
 427
 428                 //
 429                 // ACTIONS
 430                 //
 431
 432                 /**
 433                  * Cancels the running insert.
 434                  */
 435                 @SuppressWarnings("synthetic-access")
 436                 public void cancel() {
 437                         clientPutter.cancel(node.clientCore.clientContext);
 438                         eventBus.post(new ImageInsertAbortedEvent(image));
 439                         bucket.free();
 440                 }
 441
 442                 //
 443                 // INTERFACE ClientPutCallback
 444                 //
 445
 446                 @Override
 447                 public RequestClient getRequestClient() {
 448                         return imageInserts;
 449                 }
 450
 451                 @Override
 452                 public void onResume(ClientContext context) throws ResumeFailedException {
 453                         /* ignore. */
 454                 }
 455
 456                 /**
 457                  * {@inheritDoc}
 458                  */
 459                 @Override
 460                 @SuppressWarnings("synthetic-access")
 461                 public void onFailure(InsertException insertException, BaseClientPutter clientPutter) {
 462                         if ((insertException != null) && ("Cancelled by user".equals(insertException.getMessage()))) {
 463                                 eventBus.post(new ImageInsertAbortedEvent(image));
 464                         } else {
 465                                 eventBus.post(new ImageInsertFailedEvent(image, insertException));
 466                         }
 467                         bucket.free();
 468                 }
 469
 470                 /**
 471                  * {@inheritDoc}
 472                  */
 473                 @Override
 474                 public void onFetchable(BaseClientPutter clientPutter) {
 475                         /* ignore, we don’t care. */
 476                 }
 477
 478                 /**
 479                  * {@inheritDoc}
 480                  */
 481                 @Override
 482                 public void onGeneratedMetadata(Bucket metadata, BaseClientPutter clientPutter) {
 483                         /* ignore, we don’t care. */
 484                 }
 485
 486                 /**
 487                  * {@inheritDoc}
 488                  */
 489                 @Override
 490                 public void onGeneratedURI(FreenetURI generatedUri, BaseClientPutter clientPutter) {
 491                         resultingUri = generatedUri;
 492                 }
 493
 494                 /**
 495                  * {@inheritDoc}
 496                  */
 497                 @Override
 498                 @SuppressWarnings("synthetic-access")
 499                 public void onSuccess(BaseClientPutter clientPutter) {
 500                         eventBus.post(new ImageInsertFinishedEvent(image, resultingUri));
 501                         bucket.free();
 502                 }
 503
 504         }
 505
 506         public static class InsertTokenSupplier implements Function<Image, InsertToken> {
 507
 508                 private final FreenetInterface freenetInterface;
 509
 510                 @Inject
 511                 public InsertTokenSupplier(FreenetInterface freenetInterface) {
 512                         this.freenetInterface = freenetInterface;
 513                 }
 514
 515                 @Override
 516                 public InsertToken apply(Image image) {
 517                         return freenetInterface.new InsertToken(image);
 518                 }
 519
 520         }
 521
 522 }