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