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