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.binding.api.DataObjectModification.ModificationType.DELETE;
  11 import static org.opendaylight.controller.md.sal.binding.api.DataObjectModification.ModificationType.WRITE;
  12 import static org.opendaylight.controller.md.sal.common.api.data.LogicalDatastoreType.CONFIGURATION;
  13 import static org.opendaylight.controller.md.sal.common.api.data.LogicalDatastoreType.OPERATIONAL;
  14 import static org.opendaylight.yangtools.yang.common.RpcError.ErrorType.APPLICATION;
  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 dataBroker;
  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 setDataBroker(final DataBroker dataBroker) {
 104         this.dataBroker = dataBroker;
 105         dataBroker.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 (dataBroker != null) {
 118             dataTreeChangeListenerRegistration.close();
 119
 120             WriteTransaction tx = dataBroker.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 failure) {
 130                     LOG.error("Delete of Toaster failed", failure);
 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()).setToasterStatus(status).build();
 142     }
 143
 144     /**
 145      * Implemented from the DataTreeChangeListener interface.
 146      */
 147     @Override
 148     public void onDataTreeChanged(Collection<DataTreeModification<Toaster>> changes) {
 149         for (DataTreeModification<Toaster> change: changes) {
 150             DataObjectModification<Toaster> rootNode = change.getRootNode();
 151             if (rootNode.getModificationType() == WRITE) {
 152                 Toaster oldToaster = rootNode.getDataBefore();
 153                 Toaster newToaster = rootNode.getDataAfter();
 154                 LOG.info("onDataTreeChanged - Toaster config with path {} was added or replaced: "
 155                         + "old Toaster: {}, new Toaster: {}", change.getRootPath().getRootIdentifier(),
 156                         oldToaster, newToaster);
 157
 158                 Long darkness = newToaster.getDarknessFactor();
 159                 if (darkness != null) {
 160                     darknessFactor.set(darkness);
 161                 }
 162             } else if (rootNode.getModificationType() == DELETE) {
 163                 LOG.info("onDataTreeChanged - Toaster config with path {} was deleted: old Toaster: {}",
 164                         change.getRootPath().getRootIdentifier(), rootNode.getDataBefore());
 165             }
 166         }
 167     }
 168
 169     /**
 170      * RPC call implemented from the ToasterService interface that cancels the current toast, if any.
 171      */
 172     @Override
 173     public Future<RpcResult<Void>> cancelToast() {
 174         Future<?> current = currentMakeToastTask.getAndSet(null);
 175         if (current != null) {
 176             current.cancel(true);
 177         }
 178
 179         // Always return success from the cancel toast call
 180         return Futures.immediateFuture(RpcResultBuilder.<Void>success().build());
 181     }
 182
 183     /**
 184      * RPC call implemented from the ToasterService interface that attempts to make toast.
 185      */
 186     @Override
 187     public Future<RpcResult<Void>> makeToast(final MakeToastInput input) {
 188         LOG.info("makeToast: " + input);
 189
 190         final SettableFuture<RpcResult<Void>> futureResult = SettableFuture.create();
 191
 192         checkStatusAndMakeToast(input, futureResult, toasterAppConfig.getMaxMakeToastTries());
 193
 194         return futureResult;
 195     }
 196
 197     private RpcError makeToasterOutOfBreadError() {
 198         return RpcResultBuilder.newError(APPLICATION, "resource-denied", "Toaster is out of bread", "out-of-stock",
 199                 null, null);
 200     }
 201
 202     private RpcError makeToasterInUseError() {
 203         return RpcResultBuilder.newWarning(APPLICATION, "in-use", "Toaster is busy", null, null, null);
 204     }
 205
 206     private void checkStatusAndMakeToast(final MakeToastInput input, final SettableFuture<RpcResult<Void>> futureResult,
 207             final int tries) {
 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         final ReadWriteTransaction tx = dataBroker.newReadWriteTransaction();
 212         ListenableFuture<Optional<Toaster>> readFuture = tx.read(OPERATIONAL, TOASTER_IID);
 213
 214         final ListenableFuture<Void> commitFuture =
 215             Futures.transform(readFuture, (AsyncFunction<Optional<Toaster>, Void>) toasterData -> {
 216                 ToasterStatus toasterStatus = ToasterStatus.Up;
 217                 if (toasterData.isPresent()) {
 218                     toasterStatus = 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                         return Futures.immediateFailedCheckedFuture(
 228                                 new TransactionCommitFailedException("", makeToasterOutOfBreadError()));
 229                     }
 230
 231                     LOG.debug("Setting Toaster status to Down");
 232
 233                     // We're not currently making toast - try to update the status to Down
 234                     // to indicate we're going to make toast. This acts as a lock to prevent
 235                     // concurrent toasting.
 236                     tx.put(OPERATIONAL, TOASTER_IID, buildToaster(ToasterStatus.Down));
 237                     return tx.submit();
 238                 }
 239
 240                 LOG.debug("Oops - already making toast!");
 241
 242                 // Return an error since we are already making toast. This will get
 243                 // propagated to the commitFuture below which will interpret the null
 244                 // TransactionStatus in the RpcResult as an error condition.
 245                 return Futures.immediateFailedCheckedFuture(
 246                         new TransactionCommitFailedException("", makeToasterInUseError()));
 247             });
 248
 249         Futures.addCallback(commitFuture, new FutureCallback<Void>() {
 250             @Override
 251             public void onSuccess(final Void result) {
 252                 // OK to make toast
 253                 currentMakeToastTask.set(executor.submit(new MakeToastTask(input, futureResult)));
 254             }
 255
 256             @Override
 257             public void onFailure(final Throwable ex) {
 258                 if (ex instanceof OptimisticLockFailedException) {
 259
 260                     // Another thread is likely trying to make toast simultaneously and updated the
 261                     // status before us. Try reading the status again - if another make toast is
 262                     // now in progress, we should get ToasterStatus.Down and fail.
 263
 264                     if (tries - 1 > 0) {
 265                         LOG.debug("Got OptimisticLockFailedException - trying again");
 266                         checkStatusAndMakeToast(input, futureResult, tries - 1);
 267                     } else {
 268                         futureResult.set(RpcResultBuilder.<Void>failed()
 269                                 .withError(ErrorType.APPLICATION, ex.getMessage()).build());
 270                     }
 271                 } else if (ex instanceof TransactionCommitFailedException) {
 272                     LOG.debug("Failed to commit Toaster status", ex);
 273
 274                     // Probably already making toast.
 275                     futureResult.set(RpcResultBuilder.<Void>failed()
 276                             .withRpcErrors(((TransactionCommitFailedException)ex).getErrorList()).build());
 277                 } else {
 278                     LOG.debug("Unexpected error committing Toaster status", ex);
 279                     futureResult.set(RpcResultBuilder.<Void>failed().withError(ErrorType.APPLICATION,
 280                             "Unexpected error committing Toaster status", ex).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.offerNotification(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         WriteTransaction tx = dataBroker.newWriteOnlyTransaction();
 325         tx.put(OPERATIONAL,TOASTER_IID, buildToaster(ToasterStatus.Up));
 326
 327         Futures.addCallback(tx.submit(), new FutureCallback<Void>() {
 328             @Override
 329             public void onSuccess(final Void result) {
 330                 notifyCallback(true);
 331             }
 332
 333             @Override
 334             public void onFailure(final Throwable failure) {
 335                 // We shouldn't get an OptimisticLockFailedException (or any ex) as no
 336                 // other component should be updating the operational state.
 337                 LOG.error("Failed to update toaster status", failure);
 338
 339                 notifyCallback(false);
 340             }
 341
 342             void notifyCallback(final boolean result) {
 343                 if (resultCallback != null) {
 344                     resultCallback.apply(result);
 345                 }
 346             }
 347         });
 348     }
 349
 350     private boolean outOfBread() {
 351         return amountOfBreadInStock.get() == 0;
 352     }
 353
 354     private class MakeToastTask implements Callable<Void> {
 355
 356         final MakeToastInput toastRequest;
 357         final SettableFuture<RpcResult<Void>> futureResult;
 358
 359         MakeToastTask(final MakeToastInput toastRequest, final SettableFuture<RpcResult<Void>> futureResult) {
 360             this.toastRequest = toastRequest;
 361             this.futureResult = futureResult;
 362         }
 363
 364         @Override
 365         public Void call() {
 366             try {
 367                 // make toast just sleeps for n seconds per doneness level.
 368                 Thread.sleep(OpendaylightToaster.this.darknessFactor.get() * toastRequest.getToasterDoneness());
 369
 370             } catch (InterruptedException e) {
 371                 LOG.info("Interrupted while making the toast");
 372             }
 373
 374             toastsMade.incrementAndGet();
 375
 376             amountOfBreadInStock.getAndDecrement();
 377             if (outOfBread()) {
 378                 LOG.info("Toaster is out of bread!");
 379
 380                 notificationProvider.offerNotification(new ToasterOutOfBreadBuilder().build());
 381             }
 382
 383             // Set the Toaster status back to up - this essentially releases the toasting lock.
 384             // We can't clear the current toast task nor set the Future result until the
 385             // update has been committed so we pass a callback to be notified on completion.
 386
 387             setToasterStatusUp(result -> {
 388                 currentMakeToastTask.set(null);
 389                 LOG.debug("Toast done");
 390                 futureResult.set(RpcResultBuilder.<Void>success().build());
 391                 return null;
 392             });
 393
 394             return null;
 395         }
 396     }
 397 }