opendaylight/md-sal/samples/toaster-provider/src/main/java/org/opendaylight/controller/sample/toaster/provider/OpendaylightToaster.java

   1 /*
   2  * Copyright (c) 2014 Cisco Systems, Inc. and others.  All rights reserved.
   3  *
   4  * This program and the accompanying materials are made available under the
   5  * terms of the Eclipse Public License v1.0 which accompanies this distribution,
   6  * and is available at http://www.eclipse.org/legal/epl-v10.html
   7  */
   8 package org.opendaylight.controller.sample.toaster.provider;
   9
  10 import static java.util.Objects.requireNonNull;
  11 import static org.opendaylight.mdsal.common.api.LogicalDatastoreType.CONFIGURATION;
  12 import static org.opendaylight.mdsal.common.api.LogicalDatastoreType.OPERATIONAL;
  13 import static org.opendaylight.yangtools.yang.common.ErrorType.APPLICATION;
  14
  15 import com.google.common.util.concurrent.FluentFuture;
  16 import com.google.common.util.concurrent.FutureCallback;
  17 import com.google.common.util.concurrent.Futures;
  18 import com.google.common.util.concurrent.ListenableFuture;
  19 import com.google.common.util.concurrent.MoreExecutors;
  20 import com.google.common.util.concurrent.SettableFuture;
  21 import java.util.List;
  22 import java.util.Optional;
  23 import java.util.concurrent.Callable;
  24 import java.util.concurrent.ExecutionException;
  25 import java.util.concurrent.ExecutorService;
  26 import java.util.concurrent.Executors;
  27 import java.util.concurrent.Future;
  28 import java.util.concurrent.atomic.AtomicLong;
  29 import java.util.concurrent.atomic.AtomicReference;
  30 import java.util.function.Function;
  31 import javax.annotation.PreDestroy;
  32 import javax.inject.Inject;
  33 import javax.inject.Singleton;
  34 import org.eclipse.jdt.annotation.NonNull;
  35 import org.opendaylight.controller.md.sal.common.util.jmx.AbstractMXBean;
  36 import org.opendaylight.mdsal.binding.api.DataBroker;
  37 import org.opendaylight.mdsal.binding.api.DataTreeChangeListener;
  38 import org.opendaylight.mdsal.binding.api.DataTreeIdentifier;
  39 import org.opendaylight.mdsal.binding.api.DataTreeModification;
  40 import org.opendaylight.mdsal.binding.api.NotificationPublishService;
  41 import org.opendaylight.mdsal.binding.api.ReadWriteTransaction;
  42 import org.opendaylight.mdsal.binding.api.RpcProviderService;
  43 import org.opendaylight.mdsal.binding.api.WriteTransaction;
  44 import org.opendaylight.mdsal.common.api.CommitInfo;
  45 import org.opendaylight.mdsal.common.api.OptimisticLockFailedException;
  46 import org.opendaylight.mdsal.common.api.TransactionCommitFailedException;
  47 import org.opendaylight.yang.gen.v1.http.netconfcentral.org.ns.toaster.rev091120.CancelToast;
  48 import org.opendaylight.yang.gen.v1.http.netconfcentral.org.ns.toaster.rev091120.CancelToastInput;
  49 import org.opendaylight.yang.gen.v1.http.netconfcentral.org.ns.toaster.rev091120.CancelToastOutput;
  50 import org.opendaylight.yang.gen.v1.http.netconfcentral.org.ns.toaster.rev091120.CancelToastOutputBuilder;
  51 import org.opendaylight.yang.gen.v1.http.netconfcentral.org.ns.toaster.rev091120.DisplayString;
  52 import org.opendaylight.yang.gen.v1.http.netconfcentral.org.ns.toaster.rev091120.MakeToast;
  53 import org.opendaylight.yang.gen.v1.http.netconfcentral.org.ns.toaster.rev091120.MakeToastInput;
  54 import org.opendaylight.yang.gen.v1.http.netconfcentral.org.ns.toaster.rev091120.MakeToastOutput;
  55 import org.opendaylight.yang.gen.v1.http.netconfcentral.org.ns.toaster.rev091120.MakeToastOutputBuilder;
  56 import org.opendaylight.yang.gen.v1.http.netconfcentral.org.ns.toaster.rev091120.RestockToaster;
  57 import org.opendaylight.yang.gen.v1.http.netconfcentral.org.ns.toaster.rev091120.RestockToasterInput;
  58 import org.opendaylight.yang.gen.v1.http.netconfcentral.org.ns.toaster.rev091120.RestockToasterOutput;
  59 import org.opendaylight.yang.gen.v1.http.netconfcentral.org.ns.toaster.rev091120.RestockToasterOutputBuilder;
  60 import org.opendaylight.yang.gen.v1.http.netconfcentral.org.ns.toaster.rev091120.Toaster;
  61 import org.opendaylight.yang.gen.v1.http.netconfcentral.org.ns.toaster.rev091120.Toaster.ToasterStatus;
  62 import org.opendaylight.yang.gen.v1.http.netconfcentral.org.ns.toaster.rev091120.ToasterBuilder;
  63 import org.opendaylight.yang.gen.v1.http.netconfcentral.org.ns.toaster.rev091120.ToasterOutOfBreadBuilder;
  64 import org.opendaylight.yang.gen.v1.http.netconfcentral.org.ns.toaster.rev091120.ToasterRestocked;
  65 import org.opendaylight.yang.gen.v1.http.netconfcentral.org.ns.toaster.rev091120.ToasterRestockedBuilder;
  66 import org.opendaylight.yangtools.concepts.Registration;
  67 import org.opendaylight.yangtools.yang.binding.InstanceIdentifier;
  68 import org.opendaylight.yangtools.yang.common.ErrorTag;
  69 import org.opendaylight.yangtools.yang.common.ErrorType;
  70 import org.opendaylight.yangtools.yang.common.RpcError;
  71 import org.opendaylight.yangtools.yang.common.RpcResult;
  72 import org.opendaylight.yangtools.yang.common.RpcResultBuilder;
  73 import org.osgi.service.component.annotations.Activate;
  74 import org.osgi.service.component.annotations.Component;
  75 import org.osgi.service.component.annotations.Deactivate;
  76 import org.osgi.service.component.annotations.Reference;
  77 import org.osgi.service.metatype.annotations.AttributeDefinition;
  78 import org.osgi.service.metatype.annotations.Designate;
  79 import org.osgi.service.metatype.annotations.ObjectClassDefinition;
  80 import org.slf4j.Logger;
  81 import org.slf4j.LoggerFactory;
  82
  83 @Singleton
  84 @Component(service = MakeToast.class, immediate = true)
  85 @Designate(ocd = OpendaylightToaster.Configuration.class)
  86 public final class OpendaylightToaster extends AbstractMXBean
  87         implements MakeToast, ToasterProviderRuntimeMXBean, DataTreeChangeListener<Toaster>, AutoCloseable {
  88     @ObjectClassDefinition
  89     public @interface Configuration {
  90         @AttributeDefinition(description = "The name of the toaster's manufacturer", max = "255")
  91         String manufacturer() default TOASTER_MANUFACTURER;
  92         @AttributeDefinition(description = "The name of the toaster's model", max = "255")
  93         String modelNumber() default TOASTER_MODEL_NUMBER;
  94         @AttributeDefinition(description = "How many times we attempt to make toast before failing ",
  95             min = "0", max = "65535")
  96         int maxMakeToastTries() default 2;
  97     }
  98
  99     private static final CancelToastOutput EMPTY_CANCEL_OUTPUT = new CancelToastOutputBuilder().build();
 100     private static final MakeToastOutput EMPTY_MAKE_OUTPUT = new MakeToastOutputBuilder().build();
 101     private static final RestockToasterOutput EMPTY_RESTOCK_OUTPUT = new RestockToasterOutputBuilder().build();
 102
 103     private static final Logger LOG = LoggerFactory.getLogger(OpendaylightToaster.class);
 104
 105     private static final InstanceIdentifier<Toaster> TOASTER_IID = InstanceIdentifier.builder(Toaster.class).build();
 106     private static final String TOASTER_MANUFACTURER = "Opendaylight";
 107     private static final String TOASTER_MODEL_NUMBER = "Model 1 - Binding Aware";
 108
 109     private final DataBroker dataBroker;
 110     private final NotificationPublishService notificationProvider;
 111     private final Registration dataTreeChangeListenerRegistration;
 112     private final Registration reg;
 113
 114     private final ExecutorService executor;
 115
 116     // This holds the Future for the current make toast task and is used to cancel the current toast.
 117     private final AtomicReference<Future<?>> currentMakeToastTask = new AtomicReference<>();
 118
 119     // Thread safe holders
 120     private final AtomicLong amountOfBreadInStock = new AtomicLong(100);
 121     private final AtomicLong toastsMade = new AtomicLong(0);
 122     private final AtomicLong darknessFactor = new AtomicLong(1000);
 123
 124     private final @NonNull DisplayString manufacturer;
 125     private final @NonNull DisplayString modelNumber;
 126     private final int maxMakeToastTries;
 127
 128     public OpendaylightToaster(final DataBroker dataProvider,
 129             final NotificationPublishService notificationPublishService, final RpcProviderService rpcProviderService,
 130             final String manufacturer, final String modelNumber, final int maxMakeToastTries) {
 131         super("OpendaylightToaster", "toaster-provider", null);
 132         notificationProvider = requireNonNull(notificationPublishService);
 133         dataBroker = requireNonNull(dataProvider);
 134
 135         this.manufacturer = new DisplayString(manufacturer);
 136         this.modelNumber = new DisplayString(modelNumber);
 137         this.maxMakeToastTries = maxMakeToastTries;
 138
 139         executor = Executors.newFixedThreadPool(1);
 140         reg = rpcProviderService.registerRpcImplementations(
 141             (CancelToast) this::cancelToast,
 142             this,
 143             (RestockToaster) this::restockToaster);
 144
 145         LOG.info("Initializing...");
 146
 147         dataTreeChangeListenerRegistration = requireNonNull(dataBroker, "dataBroker must be set")
 148             .registerTreeChangeListener(DataTreeIdentifier.of(CONFIGURATION, TOASTER_IID), this);
 149         try {
 150             setToasterStatusUp(null).get();
 151         } catch (InterruptedException | ExecutionException e) {
 152             throw new IllegalStateException("Failed to commit initial data", e);
 153         }
 154
 155         // Register our MXBean.
 156         register();
 157     }
 158
 159     @Inject
 160     public OpendaylightToaster(final DataBroker dataProvider,
 161             final NotificationPublishService notificationPublishService, final RpcProviderService rpcProviderService) {
 162         this(dataProvider, notificationPublishService, rpcProviderService, TOASTER_MANUFACTURER, TOASTER_MODEL_NUMBER,
 163             2);
 164     }
 165
 166     @Activate
 167     public OpendaylightToaster(@Reference final DataBroker dataProvider,
 168             @Reference final NotificationPublishService notificationPublishService,
 169             @Reference final RpcProviderService rpcProviderService, final @NonNull Configuration configuration) {
 170         this(dataProvider, notificationPublishService, rpcProviderService, configuration.manufacturer(),
 171             configuration.modelNumber(), configuration.maxMakeToastTries());
 172     }
 173
 174     /**
 175      * Implemented from the AutoCloseable interface.
 176      */
 177     @Override
 178     @PreDestroy
 179     @Deactivate
 180     public void close() {
 181         LOG.info("Closing...");
 182
 183         // Unregister our MXBean.
 184         unregister();
 185         reg.close();
 186
 187         // When we close this service we need to shutdown our executor!
 188         executor.shutdown();
 189
 190         if (dataTreeChangeListenerRegistration != null) {
 191             dataTreeChangeListenerRegistration.close();
 192         }
 193
 194         if (dataBroker != null) {
 195             WriteTransaction tx = dataBroker.newWriteOnlyTransaction();
 196             tx.delete(OPERATIONAL,TOASTER_IID);
 197             Futures.addCallback(tx.commit(), new FutureCallback<CommitInfo>() {
 198                 @Override
 199                 public void onSuccess(final CommitInfo result) {
 200                     LOG.debug("Successfully deleted the operational Toaster");
 201                 }
 202
 203                 @Override
 204                 public void onFailure(final Throwable failure) {
 205                     LOG.error("Delete of the operational Toaster failed", failure);
 206                 }
 207             }, MoreExecutors.directExecutor());
 208         }
 209     }
 210
 211     private Toaster buildToaster(final ToasterStatus status) {
 212         // note - we are simulating a device whose manufacture and model are
 213         // fixed (embedded) into the hardware.
 214         // This is why the manufacture and model number are hardcoded.
 215         return new ToasterBuilder()
 216             .setToasterManufacturer(manufacturer)
 217             .setToasterModelNumber(modelNumber)
 218             .setToasterStatus(status)
 219             .build();
 220     }
 221
 222     /**
 223      * Implemented from the DataTreeChangeListener interface.
 224      */
 225     @Override
 226     public void onDataTreeChanged(final List<DataTreeModification<Toaster>> changes) {
 227         for (var change: changes) {
 228             final var rootNode = change.getRootNode();
 229             switch (rootNode.modificationType()) {
 230                 case WRITE -> {
 231                     final var oldToaster = rootNode.dataBefore();
 232                     final var newToaster = rootNode.dataAfter();
 233                     LOG.info("onDataTreeChanged - Toaster config with path {} was added or replaced: old Toaster: {}, "
 234                         + "new Toaster: {}", change.getRootPath().path(), oldToaster, newToaster);
 235
 236                     final var darkness = newToaster.getDarknessFactor();
 237                     if (darkness != null) {
 238                         darknessFactor.set(darkness.toJava());
 239                     }
 240                 }
 241                 case DELETE -> LOG.info("onDataTreeChanged - Toaster config with path {} was deleted: old Toaster: {}",
 242                         change.getRootPath().path(), rootNode.dataBefore());
 243                 default -> {
 244                     // No-op
 245                 }
 246             }
 247         }
 248     }
 249
 250     /**
 251      * RPC call implemented from the ToasterService interface that cancels the current toast, if any.
 252      */
 253     private ListenableFuture<RpcResult<CancelToastOutput>> cancelToast(final CancelToastInput input) {
 254         final var current = currentMakeToastTask.getAndSet(null);
 255         if (current != null) {
 256             current.cancel(true);
 257         }
 258
 259         // Always return success from the cancel toast call
 260         return Futures.immediateFuture(RpcResultBuilder.success(EMPTY_CANCEL_OUTPUT).build());
 261     }
 262
 263     /**
 264      * RPC call implemented from the ToasterService interface that attempts to make toast.
 265      */
 266     @Override
 267     public ListenableFuture<RpcResult<MakeToastOutput>> invoke(final MakeToastInput input) {
 268         LOG.info("makeToast: {}", input);
 269         final var futureResult = SettableFuture.<RpcResult<MakeToastOutput>>create();
 270         checkStatusAndMakeToast(input, futureResult, maxMakeToastTries);
 271         return futureResult;
 272     }
 273
 274     private static RpcError makeToasterOutOfBreadError() {
 275         return RpcResultBuilder.newError(APPLICATION, ErrorTag.RESOURCE_DENIED, "Toaster is out of bread",
 276             "out-of-stock", null, null);
 277     }
 278
 279     private static RpcError makeToasterInUseError() {
 280         return RpcResultBuilder.newWarning(APPLICATION, ErrorTag.IN_USE, "Toaster is busy", null, null, null);
 281     }
 282
 283     private void checkStatusAndMakeToast(final MakeToastInput input,
 284             final SettableFuture<RpcResult<MakeToastOutput>> futureResult, final int tries) {
 285         // Read the ToasterStatus and, if currently Up, try to write the status to Down.
 286         // If that succeeds, then we essentially have an exclusive lock and can proceed
 287         // to make toast.
 288         final ReadWriteTransaction tx = dataBroker.newReadWriteTransaction();
 289         FluentFuture<Optional<Toaster>> readFuture = tx.read(OPERATIONAL, TOASTER_IID);
 290
 291         final ListenableFuture<? extends CommitInfo> commitFuture =
 292             Futures.transformAsync(readFuture, toasterData -> {
 293                 ToasterStatus toasterStatus = ToasterStatus.Up;
 294                 if (toasterData.isPresent()) {
 295                     toasterStatus = toasterData.orElseThrow().getToasterStatus();
 296                 }
 297
 298                 LOG.debug("Read toaster status: {}", toasterStatus);
 299
 300                 if (toasterStatus == ToasterStatus.Up) {
 301
 302                     if (outOfBread()) {
 303                         LOG.debug("Toaster is out of bread");
 304                         tx.cancel();
 305                         return Futures.immediateFailedFuture(
 306                                 new TransactionCommitFailedException("", makeToasterOutOfBreadError()));
 307                     }
 308
 309                     LOG.debug("Setting Toaster status to Down");
 310
 311                     // We're not currently making toast - try to update the status to Down
 312                     // to indicate we're going to make toast. This acts as a lock to prevent
 313                     // concurrent toasting.
 314                     tx.put(OPERATIONAL, TOASTER_IID, buildToaster(ToasterStatus.Down));
 315                     return tx.commit();
 316                 }
 317
 318                 LOG.debug("Oops - already making toast!");
 319
 320                 // Return an error since we are already making toast. This will get
 321                 // propagated to the commitFuture below which will interpret the null
 322                 // TransactionStatus in the RpcResult as an error condition.
 323                 tx.cancel();
 324                 return Futures.immediateFailedFuture(
 325                         new TransactionCommitFailedException("", makeToasterInUseError()));
 326             }, MoreExecutors.directExecutor());
 327
 328         Futures.addCallback(commitFuture, new FutureCallback<CommitInfo>() {
 329             @Override
 330             public void onSuccess(final CommitInfo result) {
 331                 // OK to make toast
 332                 currentMakeToastTask.set(executor.submit(new MakeToastTask(input, futureResult)));
 333             }
 334
 335             @Override
 336             public void onFailure(final Throwable ex) {
 337                 if (ex instanceof OptimisticLockFailedException) {
 338
 339                     // Another thread is likely trying to make toast simultaneously and updated the
 340                     // status before us. Try reading the status again - if another make toast is
 341                     // now in progress, we should get ToasterStatus.Down and fail.
 342
 343                     if (tries - 1 > 0) {
 344                         LOG.debug("Got OptimisticLockFailedException - trying again");
 345                         checkStatusAndMakeToast(input, futureResult, tries - 1);
 346                     } else {
 347                         futureResult.set(RpcResultBuilder.<MakeToastOutput>failed()
 348                                 .withError(ErrorType.APPLICATION, ex.getMessage()).build());
 349                     }
 350                 } else if (ex instanceof TransactionCommitFailedException) {
 351                     LOG.debug("Failed to commit Toaster status", ex);
 352
 353                     // Probably already making toast.
 354                     futureResult.set(RpcResultBuilder.<MakeToastOutput>failed()
 355                             .withRpcErrors(((TransactionCommitFailedException)ex).getErrorList()).build());
 356                 } else {
 357                     LOG.debug("Unexpected error committing Toaster status", ex);
 358                     futureResult.set(RpcResultBuilder.<MakeToastOutput>failed().withError(ErrorType.APPLICATION,
 359                             "Unexpected error committing Toaster status", ex).build());
 360                 }
 361             }
 362         }, MoreExecutors.directExecutor());
 363     }
 364
 365     /**
 366      * RestConf RPC call implemented from the ToasterService interface.
 367      * Restocks the bread for the toaster, resets the toastsMade counter to 0, and sends a
 368      * ToasterRestocked notification.
 369      */
 370     private ListenableFuture<RpcResult<RestockToasterOutput>> restockToaster(final RestockToasterInput input) {
 371         LOG.info("restockToaster: {}", input);
 372
 373         amountOfBreadInStock.set(input.getAmountOfBreadToStock().toJava());
 374
 375         if (amountOfBreadInStock.get() > 0) {
 376             ToasterRestocked reStockedNotification = new ToasterRestockedBuilder()
 377                     .setAmountOfBread(input.getAmountOfBreadToStock()).build();
 378             notificationProvider.offerNotification(reStockedNotification);
 379         }
 380
 381         return Futures.immediateFuture(RpcResultBuilder.success(EMPTY_RESTOCK_OUTPUT).build());
 382     }
 383
 384     /**
 385      * JMX RPC call implemented from the ToasterProviderRuntimeMXBean interface.
 386      */
 387     @Override
 388     public void clearToastsMade() {
 389         LOG.info("clearToastsMade");
 390         toastsMade.set(0);
 391     }
 392
 393     /**
 394      * Accesssor method implemented from the ToasterProviderRuntimeMXBean interface.
 395      */
 396     @Override
 397     public Long getToastsMade() {
 398         return toastsMade.get();
 399     }
 400
 401     private ListenableFuture<?> setToasterStatusUp(final Function<Boolean, MakeToastOutput> resultCallback) {
 402         WriteTransaction tx = dataBroker.newWriteOnlyTransaction();
 403         tx.put(OPERATIONAL,TOASTER_IID, buildToaster(ToasterStatus.Up));
 404
 405         final var future = tx.commit();
 406         Futures.addCallback(future, new FutureCallback<CommitInfo>() {
 407             @Override
 408             public void onSuccess(final CommitInfo result) {
 409                 LOG.info("Successfully set ToasterStatus to Up");
 410                 notifyCallback(true);
 411             }
 412
 413             @Override
 414             public void onFailure(final Throwable failure) {
 415                 // We shouldn't get an OptimisticLockFailedException (or any ex) as no
 416                 // other component should be updating the operational state.
 417                 LOG.error("Failed to update toaster status", failure);
 418
 419                 notifyCallback(false);
 420             }
 421
 422             void notifyCallback(final boolean result) {
 423                 if (resultCallback != null) {
 424                     resultCallback.apply(result);
 425                 }
 426             }
 427         }, MoreExecutors.directExecutor());
 428
 429         return future;
 430     }
 431
 432     private boolean outOfBread() {
 433         return amountOfBreadInStock.get() == 0;
 434     }
 435
 436     private class MakeToastTask implements Callable<Void> {
 437
 438         final MakeToastInput toastRequest;
 439         final SettableFuture<RpcResult<MakeToastOutput>> futureResult;
 440
 441         MakeToastTask(final MakeToastInput toastRequest,
 442             final SettableFuture<RpcResult<MakeToastOutput>> futureResult) {
 443             this.toastRequest = toastRequest;
 444             this.futureResult = futureResult;
 445         }
 446
 447         @Override
 448         public Void call() {
 449             try {
 450                 // make toast just sleeps for n seconds per doneness level.
 451                 Thread.sleep(darknessFactor.get()
 452                         * toastRequest.getToasterDoneness().toJava());
 453
 454             } catch (InterruptedException e) {
 455                 LOG.info("Interrupted while making the toast");
 456             }
 457
 458             toastsMade.incrementAndGet();
 459
 460             amountOfBreadInStock.getAndDecrement();
 461             if (outOfBread()) {
 462                 LOG.info("Toaster is out of bread!");
 463
 464                 notificationProvider.offerNotification(new ToasterOutOfBreadBuilder().build());
 465             }
 466
 467             // Set the Toaster status back to up - this essentially releases the toasting lock.
 468             // We can't clear the current toast task nor set the Future result until the
 469             // update has been committed so we pass a callback to be notified on completion.
 470
 471             setToasterStatusUp(result -> {
 472                 currentMakeToastTask.set(null);
 473                 LOG.debug("Toast done");
 474                 futureResult.set(RpcResultBuilder.success(EMPTY_MAKE_OUTPUT).build());
 475                 return null;
 476             });
 477
 478             return null;
 479         }
 480     }
 481 }