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