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