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