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
  36 import net.pterodactylus.sone.core.event.ImageInsertAbortedEvent;
  37 import net.pterodactylus.sone.core.event.ImageInsertFailedEvent;
  38 import net.pterodactylus.sone.core.event.ImageInsertFinishedEvent;
  39 import net.pterodactylus.sone.core.event.ImageInsertStartedEvent;
  40 import net.pterodactylus.sone.data.Image;
  41 import net.pterodactylus.sone.data.Sone;
  42 import net.pterodactylus.sone.data.TemporaryImage;
  43
  44 import com.google.common.base.Function;
  45 import com.google.common.eventbus.EventBus;
  46 import com.google.inject.Inject;
  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  * @author <a href="mailto:bombe@pterodactylus.net">David ‘Bombe’ Roden</a>
  83  */
  84 @Singleton
  85 public class FreenetInterface {
  86
  87         /** The logger. */
  88         private static final Logger logger = getLogger(FreenetInterface.class.getName());
  89
  90         /** The event bus. */
  91         private final EventBus eventBus;
  92
  93         /** The node to interact with. */
  94         private final Node node;
  95
  96         /** The high-level client to use for requests. */
  97         private final HighLevelSimpleClient client;
  98
  99         /** The USK callbacks. */
 100         private final Map<String, USKCallback> soneUskCallbacks = new HashMap<String, USKCallback>();
 101
 102         /** The not-Sone-related USK callbacks. */
 103         private final Map<FreenetURI, USKCallback> uriUskCallbacks = Collections.synchronizedMap(new HashMap<FreenetURI, USKCallback>());
 104
 105         private final RequestClient imageInserts = new RequestClientBuilder().realTime().build();
 106         private final RequestClient imageLoader = new RequestClientBuilder().realTime().build();
 107
 108         /**
 109          * Creates a new Freenet interface.
 110          *
 111          * @param eventBus
 112          *            The event bus
 113          * @param node
 114          *            The node to interact with
 115          */
 116         @Inject
 117         public FreenetInterface(EventBus eventBus, Node node) {
 118                 this.eventBus = eventBus;
 119                 this.node = node;
 120                 this.client = node.clientCore.makeClient(RequestStarter.INTERACTIVE_PRIORITY_CLASS, false, true);
 121         }
 122
 123         //
 124         // ACTIONS
 125         //
 126
 127         /**
 128          * Fetches the given URI.
 129          *
 130          * @param uri
 131          *            The URI to fetch
 132          * @return The result of the fetch, or {@code null} if an error occured
 133          */
 134         public Fetched fetchUri(FreenetURI uri) {
 135                 FreenetURI currentUri = new FreenetURI(uri);
 136                 while (true) {
 137                         try {
 138                                 FetchResult fetchResult = client.fetch(currentUri);
 139                                 return new Fetched(currentUri, fetchResult);
 140                         } catch (FetchException fe1) {
 141                                 if (fe1.getMode() == FetchExceptionMode.PERMANENT_REDIRECT) {
 142                                         currentUri = fe1.newURI;
 143                                         continue;
 144                                 }
 145                                 logger.log(Level.WARNING, String.format("Could not fetch “%s”!", uri), fe1);
 146                                 return null;
 147                         }
 148                 }
 149         }
 150
 151         public void startFetch(final FreenetURI uri, final BackgroundFetchCallback backgroundFetchCallback) {
 152                 ClientGetCallback callback = new ClientGetCallback() {
 153                         @Override
 154                         public void onSuccess(FetchResult result, ClientGetter state) {
 155                                 try {
 156                                         backgroundFetchCallback.loaded(uri, result.getMimeType(), result.asByteArray());
 157                                 } catch (IOException e) {
 158                                         backgroundFetchCallback.failed(uri);
 159                                 }
 160                         }
 161
 162                         @Override
 163                         public void onFailure(FetchException e, ClientGetter state) {
 164                                 backgroundFetchCallback.failed(uri);
 165                         }
 166
 167                         @Override
 168                         public void onResume(ClientContext context) throws ResumeFailedException {
 169                                 /* do nothing. */
 170                         }
 171
 172                         @Override
 173                         public RequestClient getRequestClient() {
 174                                 return imageLoader;
 175                         }
 176                 };
 177                 SnoopMetadata snoop = new SnoopMetadata() {
 178                         @Override
 179                         public boolean snoopMetadata(Metadata meta, ClientContext context) {
 180                                 String mimeType = meta.getMIMEType();
 181                                 boolean cancel = (mimeType == null) || backgroundFetchCallback.shouldCancel(uri, mimeType, meta.dataLength());
 182                                 if (cancel) {
 183                                         backgroundFetchCallback.failed(uri);
 184                                 }
 185                                 return cancel;
 186                         }
 187                 };
 188                 FetchContext fetchContext = client.getFetchContext();
 189                 try {
 190                         ClientGetter clientGetter = client.fetch(uri, 2097152, callback, fetchContext, RequestStarter.INTERACTIVE_PRIORITY_CLASS);
 191                         clientGetter.setMetaSnoop(snoop);
 192                         clientGetter.restart(uri, fetchContext.filterData, node.clientCore.clientContext);
 193                 } catch (FetchException fe) {
 194                         /* stupid exception that can not actually be thrown! */
 195                 }
 196         }
 197
 198         public interface BackgroundFetchCallback {
 199                 boolean shouldCancel(@Nonnull FreenetURI uri, @Nonnull String mimeType, long size);
 200                 void loaded(@Nonnull FreenetURI uri, @Nonnull String mimeType, @Nonnull byte[] data);
 201                 void failed(@Nonnull FreenetURI uri);
 202         }
 203
 204         /**
 205          * Inserts the image data of the given {@link TemporaryImage} and returns
 206          * the given insert token that can be used to add listeners or cancel the
 207          * insert.
 208          *
 209          * @param temporaryImage
 210          *            The temporary image data
 211          * @param image
 212          *            The image
 213          * @param insertToken
 214          *            The insert token
 215          * @throws SoneException
 216          *             if the insert could not be started
 217          */
 218         public void insertImage(TemporaryImage temporaryImage, Image image, InsertToken insertToken) throws SoneException {
 219                 String filenameHint = image.getId() + "." + temporaryImage.getMimeType().substring(temporaryImage.getMimeType().lastIndexOf("/") + 1);
 220                 InsertableClientSSK key = InsertableClientSSK.createRandom(node.random, "");
 221                 FreenetURI targetUri = key.getInsertURI().setDocName(filenameHint);
 222                 InsertContext insertContext = client.getInsertContext(true);
 223                 RandomAccessBucket bucket = new ArrayBucket(temporaryImage.getImageData());
 224                 insertToken.setBucket(bucket);
 225                 ClientMetadata metadata = new ClientMetadata(temporaryImage.getMimeType());
 226                 InsertBlock insertBlock = new InsertBlock(bucket, metadata, targetUri);
 227                 try {
 228                         ClientPutter clientPutter = client.insert(insertBlock, null, false, insertContext, insertToken, RequestStarter.INTERACTIVE_PRIORITY_CLASS);
 229                         insertToken.setClientPutter(clientPutter);
 230                 } catch (InsertException ie1) {
 231                         throw new SoneInsertException("Could not start image insert.", ie1);
 232                 }
 233         }
 234
 235         /**
 236          * Inserts a directory into Freenet.
 237          *
 238          * @param insertUri
 239          *            The insert URI
 240          * @param manifestEntries
 241          *            The directory entries
 242          * @param defaultFile
 243          *            The name of the default file
 244          * @return The generated URI
 245          * @throws SoneException
 246          *             if an insert error occurs
 247          */
 248         public FreenetURI insertDirectory(FreenetURI insertUri, HashMap<String, Object> manifestEntries, String defaultFile) throws SoneException {
 249                 try {
 250                         return client.insertManifest(insertUri, manifestEntries, defaultFile);
 251                 } catch (InsertException ie1) {
 252                         throw new SoneException(ie1);
 253                 }
 254         }
 255
 256         public void registerActiveUsk(FreenetURI requestUri,
 257                         USKCallback uskCallback) {
 258                 try {
 259                         soneUskCallbacks.put(routingKey(requestUri), uskCallback);
 260                         node.clientCore.uskManager.subscribe(create(requestUri),
 261                                         uskCallback, true, (RequestClient) client);
 262                 } catch (MalformedURLException mue1) {
 263                         logger.log(WARNING, format("Could not subscribe USK “%s”!",
 264                                         requestUri), mue1);
 265                 }
 266         }
 267
 268         public void registerPassiveUsk(FreenetURI requestUri,
 269                         USKCallback uskCallback) {
 270                 try {
 271                         soneUskCallbacks.put(routingKey(requestUri), uskCallback);
 272                         node.clientCore
 273                                         .uskManager
 274                                         .subscribe(create(requestUri), uskCallback, false,
 275                                                         (RequestClient) client);
 276                 } catch (MalformedURLException mue1) {
 277                         logger.log(WARNING,
 278                                         format("Could not subscribe USK “%s”!", requestUri),
 279                                         mue1);
 280                 }
 281         }
 282
 283         /**
 284          * Unsubscribes the request URI of the given Sone.
 285          *
 286          * @param sone
 287          *            The Sone to unregister
 288          */
 289         public void unregisterUsk(Sone sone) {
 290                 USKCallback uskCallback = soneUskCallbacks.remove(sone.getId());
 291                 if (uskCallback == null) {
 292                         return;
 293                 }
 294                 try {
 295                         logger.log(Level.FINEST, String.format("Unsubscribing from USK for %s…", sone));
 296                         node.clientCore.uskManager.unsubscribe(USK.create(sone.getRequestUri()), uskCallback);
 297                 } catch (MalformedURLException mue1) {
 298                         logger.log(Level.FINE, String.format("Could not unsubscribe USK “%s”!", sone.getRequestUri()), mue1);
 299                 }
 300         }
 301
 302         /**
 303          * Registers an arbitrary URI and calls the given callback if a new edition
 304          * is found.
 305          *
 306          * @param uri
 307          *            The URI to watch
 308          * @param callback
 309          *            The callback to call
 310          */
 311         public void registerUsk(FreenetURI uri, final Callback callback) {
 312                 USKCallback uskCallback = new USKCallback() {
 313
 314                         @Override
 315                         public void onFoundEdition(long edition, USK key, ClientContext clientContext, boolean metadata, short codec, byte[] data, boolean newKnownGood, boolean newSlotToo) {
 316                                 callback.editionFound(key.getURI(), edition, newKnownGood, newSlotToo);
 317                         }
 318
 319                         @Override
 320                         public short getPollingPriorityNormal() {
 321                                 return RequestStarter.PREFETCH_PRIORITY_CLASS;
 322                         }
 323
 324                         @Override
 325                         public short getPollingPriorityProgress() {
 326                                 return RequestStarter.INTERACTIVE_PRIORITY_CLASS;
 327                         }
 328
 329                 };
 330                 try {
 331                         node.clientCore.uskManager.subscribe(USK.create(uri), uskCallback, true, (RequestClient) client);
 332                         uriUskCallbacks.put(uri, uskCallback);
 333                 } catch (MalformedURLException mue1) {
 334                         logger.log(Level.WARNING, String.format("Could not subscribe to USK: %s", uri), mue1);
 335                 }
 336         }
 337
 338         /**
 339          * Unregisters the USK watcher for the given URI.
 340          *
 341          * @param uri
 342          *            The URI to unregister the USK watcher for
 343          */
 344         public void unregisterUsk(FreenetURI uri) {
 345                 USKCallback uskCallback = uriUskCallbacks.remove(uri);
 346                 if (uskCallback == null) {
 347                         logger.log(Level.INFO, String.format("Could not unregister unknown USK: %s", uri));
 348                         return;
 349                 }
 350                 try {
 351                         node.clientCore.uskManager.unsubscribe(USK.create(uri), uskCallback);
 352                 } catch (MalformedURLException mue1) {
 353                         logger.log(Level.INFO, String.format("Could not unregister invalid USK: %s", uri), mue1);
 354                 }
 355         }
 356
 357         /**
 358          * Container for a fetched URI and the {@link FetchResult}.
 359          *
 360          * @author <a href="mailto:d.roden@xplosion.de">David Roden</a>
 361          */
 362         public static class Fetched {
 363
 364                 /** The fetched URI. */
 365                 private final FreenetURI freenetUri;
 366
 367                 /** The fetch result. */
 368                 private final FetchResult fetchResult;
 369
 370                 /**
 371                  * Creates a new fetched URI.
 372                  *
 373                  * @param freenetUri
 374                  *            The URI that was fetched
 375                  * @param fetchResult
 376                  *            The fetch result
 377                  */
 378                 public Fetched(FreenetURI freenetUri, FetchResult fetchResult) {
 379                         this.freenetUri = freenetUri;
 380                         this.fetchResult = fetchResult;
 381                 }
 382
 383                 //
 384                 // ACCESSORS
 385                 //
 386
 387                 /**
 388                  * Returns the fetched URI.
 389                  *
 390                  * @return The fetched URI
 391                  */
 392                 public FreenetURI getFreenetUri() {
 393                         return freenetUri;
 394                 }
 395
 396                 /**
 397                  * Returns the fetch result.
 398                  *
 399                  * @return The fetch result
 400                  */
 401                 public FetchResult getFetchResult() {
 402                         return fetchResult;
 403                 }
 404
 405         }
 406
 407         /**
 408          * Callback for USK watcher events.
 409          *
 410          * @author <a href="mailto:bombe@pterodactylus.net">David ‘Bombe’ Roden</a>
 411          */
 412         public static interface Callback {
 413
 414                 /**
 415                  * Notifies a listener that a new edition was found for a URI.
 416                  *
 417                  * @param uri
 418                  *            The URI that a new edition was found for
 419                  * @param edition
 420                  *            The found edition
 421                  * @param newKnownGood
 422                  *            Whether the found edition was actually fetched
 423                  * @param newSlot
 424                  *            Whether the found edition is higher than all previously
 425                  *            found editions
 426                  */
 427                 public void editionFound(FreenetURI uri, long edition, boolean newKnownGood, boolean newSlot);
 428
 429         }
 430
 431         /**
 432          * Insert token that can cancel a running insert and sends events.
 433          *
 434          * @see ImageInsertAbortedEvent
 435          * @see ImageInsertStartedEvent
 436          * @see ImageInsertFailedEvent
 437          * @see ImageInsertFinishedEvent
 438          * @author <a href="mailto:bombe@pterodactylus.net">David ‘Bombe’ Roden</a>
 439          */
 440         public class InsertToken implements ClientPutCallback {
 441
 442                 /** The image being inserted. */
 443                 private final Image image;
 444
 445                 /** The client putter. */
 446                 private ClientPutter clientPutter;
 447                 private Bucket bucket;
 448
 449                 /** The final URI. */
 450                 private volatile FreenetURI resultingUri;
 451
 452                 /**
 453                  * Creates a new insert token for the given image.
 454                  *
 455                  * @param image
 456                  *            The image being inserted
 457                  */
 458                 public InsertToken(Image image) {
 459                         this.image = image;
 460                 }
 461
 462                 //
 463                 // ACCESSORS
 464                 //
 465
 466                 /**
 467                  * Sets the client putter that is inserting the image. This will also
 468                  * signal all registered listeners that the image has started.
 469                  *
 470                  * @param clientPutter
 471                  *            The client putter
 472                  */
 473                 @SuppressWarnings("synthetic-access")
 474                 public void setClientPutter(ClientPutter clientPutter) {
 475                         this.clientPutter = clientPutter;
 476                         eventBus.post(new ImageInsertStartedEvent(image));
 477                 }
 478
 479                 public void setBucket(Bucket bucket) {
 480                         this.bucket = bucket;
 481                 }
 482
 483                 //
 484                 // ACTIONS
 485                 //
 486
 487                 /**
 488                  * Cancels the running insert.
 489                  */
 490                 @SuppressWarnings("synthetic-access")
 491                 public void cancel() {
 492                         clientPutter.cancel(node.clientCore.clientContext);
 493                         eventBus.post(new ImageInsertAbortedEvent(image));
 494                         bucket.free();
 495                 }
 496
 497                 //
 498                 // INTERFACE ClientPutCallback
 499                 //
 500
 501                 @Override
 502                 public RequestClient getRequestClient() {
 503                         return imageInserts;
 504                 }
 505
 506                 @Override
 507                 public void onResume(ClientContext context) throws ResumeFailedException {
 508                         /* ignore. */
 509                 }
 510
 511                 /**
 512                  * {@inheritDoc}
 513                  */
 514                 @Override
 515                 @SuppressWarnings("synthetic-access")
 516                 public void onFailure(InsertException insertException, BaseClientPutter clientPutter) {
 517                         if ((insertException != null) && ("Cancelled by user".equals(insertException.getMessage()))) {
 518                                 eventBus.post(new ImageInsertAbortedEvent(image));
 519                         } else {
 520                                 eventBus.post(new ImageInsertFailedEvent(image, insertException));
 521                         }
 522                         bucket.free();
 523                 }
 524
 525                 /**
 526                  * {@inheritDoc}
 527                  */
 528                 @Override
 529                 public void onFetchable(BaseClientPutter clientPutter) {
 530                         /* ignore, we don’t care. */
 531                 }
 532
 533                 /**
 534                  * {@inheritDoc}
 535                  */
 536                 @Override
 537                 public void onGeneratedMetadata(Bucket metadata, BaseClientPutter clientPutter) {
 538                         /* ignore, we don’t care. */
 539                 }
 540
 541                 /**
 542                  * {@inheritDoc}
 543                  */
 544                 @Override
 545                 public void onGeneratedURI(FreenetURI generatedUri, BaseClientPutter clientPutter) {
 546                         resultingUri = generatedUri;
 547                 }
 548
 549                 /**
 550                  * {@inheritDoc}
 551                  */
 552                 @Override
 553                 @SuppressWarnings("synthetic-access")
 554                 public void onSuccess(BaseClientPutter clientPutter) {
 555                         eventBus.post(new ImageInsertFinishedEvent(image, resultingUri));
 556                         bucket.free();
 557                 }
 558
 559         }
 560
 561         public class InsertTokenSupplier implements Function<Image, InsertToken> {
 562
 563                 @Override
 564                 public InsertToken apply(Image image) {
 565                         return new InsertToken(image);
 566                 }
 567
 568         }
 569
 570 }