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 com.google.common.base.Function;
  11 import com.google.common.base.Optional;
  12 import com.google.common.util.concurrent.AsyncFunction;
  13 import com.google.common.util.concurrent.FutureCallback;
  14 import com.google.common.util.concurrent.Futures;
  15 import com.google.common.util.concurrent.ListenableFuture;
  16 import com.google.common.util.concurrent.SettableFuture;
  17 import java.util.Collection;
  18 import java.util.concurrent.Callable;
  19 import java.util.concurrent.ExecutionException;
  20 import java.util.concurrent.ExecutorService;
  21 import java.util.concurrent.Executors;
  22 import java.util.concurrent.Future;
  23 import java.util.concurrent.atomic.AtomicLong;
  24 import java.util.concurrent.atomic.AtomicReference;
  25 import org.opendaylight.controller.md.sal.binding.api.DataBroker;
  26 import org.opendaylight.controller.md.sal.binding.api.DataObjectModification;
  27 import org.opendaylight.controller.md.sal.binding.api.DataTreeChangeListener;
  28 import org.opendaylight.controller.md.sal.binding.api.DataTreeIdentifier;
  29 import org.opendaylight.controller.md.sal.binding.api.DataTreeModification;
  30 import org.opendaylight.controller.md.sal.binding.api.NotificationPublishService;
  31 import org.opendaylight.controller.md.sal.binding.api.ReadWriteTransaction;
  32 import org.opendaylight.controller.md.sal.binding.api.WriteTransaction;
  33 import org.opendaylight.controller.md.sal.common.api.data.LogicalDatastoreType;
  34 import org.opendaylight.controller.md.sal.common.api.data.OptimisticLockFailedException;
  35 import org.opendaylight.controller.md.sal.common.api.data.TransactionCommitFailedException;
  36 import org.opendaylight.controller.md.sal.common.util.jmx.AbstractMXBean;
  37 import org.opendaylight.yang.gen.v1.http.netconfcentral.org.ns.toaster.rev091120.DisplayString;
  38 import org.opendaylight.yang.gen.v1.http.netconfcentral.org.ns.toaster.rev091120.MakeToastInput;
  39 import org.opendaylight.yang.gen.v1.http.netconfcentral.org.ns.toaster.rev091120.RestockToasterInput;
  40 import org.opendaylight.yang.gen.v1.http.netconfcentral.org.ns.toaster.rev091120.Toaster;
  41 import org.opendaylight.yang.gen.v1.http.netconfcentral.org.ns.toaster.rev091120.Toaster.ToasterStatus;
  42 import org.opendaylight.yang.gen.v1.http.netconfcentral.org.ns.toaster.rev091120.ToasterBuilder;
  43 import org.opendaylight.yang.gen.v1.http.netconfcentral.org.ns.toaster.rev091120.ToasterOutOfBreadBuilder;
  44 import org.opendaylight.yang.gen.v1.http.netconfcentral.org.ns.toaster.rev091120.ToasterRestocked;
  45 import org.opendaylight.yang.gen.v1.http.netconfcentral.org.ns.toaster.rev091120.ToasterRestockedBuilder;
  46 import org.opendaylight.yang.gen.v1.http.netconfcentral.org.ns.toaster.rev091120.ToasterService;
  47 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.controller.toaster.app.config.rev160503.ToasterAppConfig;
  48 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.controller.toaster.app.config.rev160503.ToasterAppConfigBuilder;
  49 import org.opendaylight.yangtools.concepts.ListenerRegistration;
  50 import org.opendaylight.yangtools.yang.binding.InstanceIdentifier;
  51 import org.opendaylight.yangtools.yang.common.RpcError;
  52 import org.opendaylight.yangtools.yang.common.RpcError.ErrorType;
  53 import org.opendaylight.yangtools.yang.common.RpcResult;
  54 import org.opendaylight.yangtools.yang.common.RpcResultBuilder;
  55 import org.slf4j.Logger;
  56 import org.slf4j.LoggerFactory;
  57
  58 public class OpendaylightToaster extends AbstractMXBean implements ToasterService, ToasterProviderRuntimeMXBean,
  59                                             DataTreeChangeListener<Toaster>, AutoCloseable {
  60
  61     private static final Logger LOG = LoggerFactory.getLogger(OpendaylightToaster.class);
  62
  63     public static final InstanceIdentifier<Toaster> TOASTER_IID = InstanceIdentifier.builder(Toaster.class).build();
  64
  65     private static final DisplayString TOASTER_MANUFACTURER = new DisplayString("Opendaylight");
  66     private static final DisplayString TOASTER_MODEL_NUMBER = new DisplayString("Model 1 - Binding Aware");
  67
  68     private NotificationPublishService notificationProvider;
  69     private DataBroker dataProvider;
  70     private ListenerRegistration<OpendaylightToaster> dataTreeChangeListenerRegistration;
  71
  72     private final ExecutorService executor;
  73
  74     // The following holds the Future for the current make toast task.
  75     // This is used to cancel the current toast.
  76     private final AtomicReference<Future<?>> currentMakeToastTask = new AtomicReference<>();
  77
  78     private final AtomicLong amountOfBreadInStock = new AtomicLong( 100 );
  79
  80     private final AtomicLong toastsMade = new AtomicLong(0);
  81
  82     // Thread safe holder for our darkness multiplier.
  83     private final AtomicLong darknessFactor = new AtomicLong( 1000 );
  84
  85     private final ToasterAppConfig toasterAppConfig;
  86
  87     public OpendaylightToaster() {
  88         this(new ToasterAppConfigBuilder().setManufacturer(TOASTER_MANUFACTURER).setModelNumber(TOASTER_MODEL_NUMBER).
  89                 setMaxMakeToastTries(2).build());
  90     }
  91
  92     public OpendaylightToaster(ToasterAppConfig toasterAppConfig) {
  93         super("OpendaylightToaster", "toaster-provider", null);
  94         executor = Executors.newFixedThreadPool(1);
  95         this.toasterAppConfig = toasterAppConfig;
  96     }
  97
  98     public void setNotificationProvider(final NotificationPublishService notificationPublishService) {
  99         this.notificationProvider = notificationPublishService;
 100     }
 101
 102     public void setDataProvider(final DataBroker salDataProvider) {
 103         this.dataProvider = salDataProvider;
 104
 105         dataProvider.registerDataTreeChangeListener(new DataTreeIdentifier<Toaster>(
 106                 LogicalDatastoreType.CONFIGURATION, OpendaylightToaster.TOASTER_IID), this);
 107
 108         setToasterStatusUp( null );
 109     }
 110
 111     /**
 112      * Implemented from the AutoCloseable interface.
 113      */
 114     @Override
 115     public void close() throws ExecutionException, InterruptedException {
 116         // When we close this service we need to shutdown our executor!
 117         executor.shutdown();
 118
 119         if (dataProvider != null) {
 120             dataTreeChangeListenerRegistration.close();
 121
 122             WriteTransaction tx = dataProvider.newWriteOnlyTransaction();
 123             tx.delete(LogicalDatastoreType.OPERATIONAL,TOASTER_IID);
 124             Futures.addCallback( tx.submit(), new FutureCallback<Void>() {
 125                 @Override
 126                 public void onSuccess( final Void result ) {
 127                     LOG.debug( "Delete Toaster commit result: " + result );
 128                 }
 129
 130                 @Override
 131                 public void onFailure( final Throwable t ) {
 132                     LOG.error( "Delete of Toaster failed", t );
 133                 }
 134             } );
 135         }
 136     }
 137
 138     private Toaster buildToaster( final ToasterStatus status ) {
 139
 140         // note - we are simulating a device whose manufacture and model are
 141         // fixed (embedded) into the hardware.
 142         // This is why the manufacture and model number are hardcoded.
 143         return new ToasterBuilder().setToasterManufacturer( toasterAppConfig.getManufacturer() )
 144                                    .setToasterModelNumber( toasterAppConfig.getModelNumber() )
 145                                    .setToasterStatus( status )
 146                                    .build();
 147     }
 148
 149     /**
 150      * Implemented from the DataTreeChangeListener interface.
 151      */
 152     @Override
 153     public void onDataTreeChanged(Collection<DataTreeModification<Toaster>> changes) {
 154         for(DataTreeModification<Toaster> change: changes) {
 155             DataObjectModification<Toaster> rootNode = change.getRootNode();
 156             if(rootNode.getModificationType() == DataObjectModification.ModificationType.WRITE) {
 157                 Toaster oldToaster = rootNode.getDataBefore();
 158                 Toaster newToaster = rootNode.getDataAfter();
 159                 LOG.info("onDataTreeChanged - Toaster config with path {} was added or replaced: old Toaster: {}, new Toaster: {}",
 160                         change.getRootPath().getRootIdentifier(), oldToaster, newToaster);
 161
 162                 Long darkness = newToaster.getDarknessFactor();
 163                 if(darkness != null) {
 164                     darknessFactor.set(darkness);
 165                 }
 166             } else if(rootNode.getModificationType() == DataObjectModification.ModificationType.DELETE) {
 167                 LOG.info("onDataTreeChanged - Toaster config with path {} was deleted: old Toaster: {}",
 168                         change.getRootPath().getRootIdentifier(), rootNode.getDataBefore());
 169             }
 170         }
 171     }
 172
 173     /**
 174      * RPC call implemented from the ToasterService interface that cancels the current
 175      * toast, if any.
 176      */
 177     @Override
 178     public Future<RpcResult<Void>> cancelToast() {
 179
 180         Future<?> current = currentMakeToastTask.getAndSet( null );
 181         if( current != null ) {
 182             current.cancel( true );
 183         }
 184
 185         // Always return success from the cancel toast call.
 186         return Futures.immediateFuture( RpcResultBuilder.<Void> success().build() );
 187     }
 188
 189     /**
 190      * RPC call implemented from the ToasterService interface that attempts to make toast.
 191      */
 192     @Override
 193     public Future<RpcResult<Void>> makeToast(final MakeToastInput input) {
 194         LOG.info("makeToast: " + input);
 195
 196         final SettableFuture<RpcResult<Void>> futureResult = SettableFuture.create();
 197
 198         checkStatusAndMakeToast( input, futureResult, toasterAppConfig.getMaxMakeToastTries() );
 199
 200         return futureResult;
 201     }
 202
 203     private RpcError makeToasterOutOfBreadError() {
 204         return RpcResultBuilder.newError( ErrorType.APPLICATION, "resource-denied",
 205                 "Toaster is out of bread", "out-of-stock", null, null );
 206     }
 207
 208     private RpcError makeToasterInUseError() {
 209         return RpcResultBuilder.newWarning( ErrorType.APPLICATION, "in-use",
 210                 "Toaster is busy", null, null, null );
 211     }
 212
 213     private void checkStatusAndMakeToast( final MakeToastInput input,
 214                                           final SettableFuture<RpcResult<Void>> futureResult,
 215                                           final int tries ) {
 216
 217         // Read the ToasterStatus and, if currently Up, try to write the status to Down.
 218         // If that succeeds, then we essentially have an exclusive lock and can proceed
 219         // to make toast.
 220
 221         final ReadWriteTransaction tx = dataProvider.newReadWriteTransaction();
 222         ListenableFuture<Optional<Toaster>> readFuture =
 223                                           tx.read( LogicalDatastoreType.OPERATIONAL, TOASTER_IID );
 224
 225         final ListenableFuture<Void> commitFuture =
 226             Futures.transform( readFuture, new AsyncFunction<Optional<Toaster>,Void>() {
 227
 228                 @Override
 229                 public ListenableFuture<Void> apply(
 230                         final Optional<Toaster> toasterData ) throws Exception {
 231
 232                     ToasterStatus toasterStatus = ToasterStatus.Up;
 233                     if( toasterData.isPresent() ) {
 234                         toasterStatus = toasterData.get().getToasterStatus();
 235                     }
 236
 237                     LOG.debug( "Read toaster status: {}", toasterStatus );
 238
 239                     if( toasterStatus == ToasterStatus.Up ) {
 240
 241                         if( outOfBread() ) {
 242                             LOG.debug( "Toaster is out of bread" );
 243
 244                             return Futures.immediateFailedCheckedFuture(
 245                                     new TransactionCommitFailedException( "", makeToasterOutOfBreadError() ) );
 246                         }
 247
 248                         LOG.debug( "Setting Toaster status to Down" );
 249
 250                         // We're not currently making toast - try to update the status to Down
 251                         // to indicate we're going to make toast. This acts as a lock to prevent
 252                         // concurrent toasting.
 253                         tx.put( LogicalDatastoreType.OPERATIONAL, TOASTER_IID,
 254                                 buildToaster( ToasterStatus.Down ) );
 255                         return tx.submit();
 256                     }
 257
 258                     LOG.debug( "Oops - already making toast!" );
 259
 260                     // Return an error since we are already making toast. This will get
 261                     // propagated to the commitFuture below which will interpret the null
 262                     // TransactionStatus in the RpcResult as an error condition.
 263                     return Futures.immediateFailedCheckedFuture(
 264                             new TransactionCommitFailedException( "", makeToasterInUseError() ) );
 265                 }
 266         } );
 267
 268         Futures.addCallback( commitFuture, new FutureCallback<Void>() {
 269             @Override
 270             public void onSuccess( final Void result ) {
 271                 // OK to make toast
 272                 currentMakeToastTask.set( executor.submit( new MakeToastTask( input, futureResult ) ) );
 273             }
 274
 275             @Override
 276             public void onFailure( final Throwable ex ) {
 277                 if( ex instanceof OptimisticLockFailedException ) {
 278
 279                     // Another thread is likely trying to make toast simultaneously and updated the
 280                     // status before us. Try reading the status again - if another make toast is
 281                     // now in progress, we should get ToasterStatus.Down and fail.
 282
 283                     if( ( tries - 1 ) > 0 ) {
 284                         LOG.debug( "Got OptimisticLockFailedException - trying again" );
 285
 286                         checkStatusAndMakeToast( input, futureResult, tries - 1 );
 287                     }
 288                     else {
 289                         futureResult.set( RpcResultBuilder.<Void> failed()
 290                                 .withError( ErrorType.APPLICATION, ex.getMessage() ).build() );
 291                     }
 292
 293                 } else {
 294
 295                     LOG.debug( "Failed to commit Toaster status", ex );
 296
 297                     // Probably already making toast.
 298                     futureResult.set( RpcResultBuilder.<Void> failed()
 299                             .withRpcErrors( ((TransactionCommitFailedException)ex).getErrorList() )
 300                             .build() );
 301                 }
 302             }
 303         } );
 304     }
 305
 306     /**
 307      * RestConf RPC call implemented from the ToasterService interface.
 308      * Restocks the bread for the toaster, resets the toastsMade counter to 0, and sends a
 309      * ToasterRestocked notification.
 310      */
 311     @Override
 312     public Future<RpcResult<java.lang.Void>> restockToaster(final RestockToasterInput input) {
 313         LOG.info( "restockToaster: " + input );
 314
 315         amountOfBreadInStock.set( input.getAmountOfBreadToStock() );
 316
 317         if( amountOfBreadInStock.get() > 0 ) {
 318             ToasterRestocked reStockedNotification = new ToasterRestockedBuilder()
 319                 .setAmountOfBread( input.getAmountOfBreadToStock() ).build();
 320             notificationProvider.offerNotification( reStockedNotification );
 321         }
 322
 323         return Futures.immediateFuture( RpcResultBuilder.<Void> success().build() );
 324     }
 325
 326     /**
 327      * JMX RPC call implemented from the ToasterProviderRuntimeMXBean interface.
 328      */
 329     @Override
 330     public void clearToastsMade() {
 331         LOG.info( "clearToastsMade" );
 332         toastsMade.set( 0 );
 333     }
 334
 335     /**
 336      * Accesssor method implemented from the ToasterProviderRuntimeMXBean interface.
 337      */
 338     @Override
 339     public Long getToastsMade() {
 340         return toastsMade.get();
 341     }
 342
 343     private void setToasterStatusUp( final Function<Boolean,Void> resultCallback ) {
 344
 345         WriteTransaction tx = dataProvider.newWriteOnlyTransaction();
 346         tx.put( LogicalDatastoreType.OPERATIONAL,TOASTER_IID, buildToaster( ToasterStatus.Up ) );
 347
 348         Futures.addCallback( tx.submit(), new FutureCallback<Void>() {
 349             @Override
 350             public void onSuccess( final Void result ) {
 351                 notifyCallback( true );
 352             }
 353
 354             @Override
 355             public void onFailure( final Throwable t ) {
 356                 // We shouldn't get an OptimisticLockFailedException (or any ex) as no
 357                 // other component should be updating the operational state.
 358                 LOG.error( "Failed to update toaster status", t );
 359
 360                 notifyCallback( false );
 361             }
 362
 363             void notifyCallback( final boolean result ) {
 364                 if( resultCallback != null ) {
 365                     resultCallback.apply( result );
 366                 }
 367             }
 368         } );
 369     }
 370
 371     private boolean outOfBread()
 372     {
 373         return amountOfBreadInStock.get() == 0;
 374     }
 375
 376     private class MakeToastTask implements Callable<Void> {
 377
 378         final MakeToastInput toastRequest;
 379         final SettableFuture<RpcResult<Void>> futureResult;
 380
 381         public MakeToastTask( final MakeToastInput toastRequest,
 382                               final SettableFuture<RpcResult<Void>> futureResult ) {
 383             this.toastRequest = toastRequest;
 384             this.futureResult = futureResult;
 385         }
 386
 387         @Override
 388         public Void call() {
 389             try
 390             {
 391                 // make toast just sleeps for n seconds per doneness level.
 392                 long darknessFactor = OpendaylightToaster.this.darknessFactor.get();
 393                 Thread.sleep(darknessFactor * toastRequest.getToasterDoneness());
 394
 395             }
 396             catch( InterruptedException e ) {
 397                 LOG.info( "Interrupted while making the toast" );
 398             }
 399
 400             toastsMade.incrementAndGet();
 401
 402             amountOfBreadInStock.getAndDecrement();
 403             if( outOfBread() ) {
 404                 LOG.info( "Toaster is out of bread!" );
 405
 406                 notificationProvider.offerNotification( new ToasterOutOfBreadBuilder().build() );
 407             }
 408
 409             // Set the Toaster status back to up - this essentially releases the toasting lock.
 410             // We can't clear the current toast task nor set the Future result until the
 411             // update has been committed so we pass a callback to be notified on completion.
 412
 413             setToasterStatusUp( new Function<Boolean,Void>() {
 414                 @Override
 415                 public Void apply( final Boolean result ) {
 416
 417                     currentMakeToastTask.set( null );
 418
 419                     LOG.debug("Toast done");
 420
 421                     futureResult.set( RpcResultBuilder.<Void>success().build() );
 422
 423                     return null;
 424                 }
 425             } );
 426
 427             return null;
 428         }
 429     }
 430 }