opendaylight/md-sal/sal-inmemory-datastore/src/main/java/org/opendaylight/controller/md/sal/dom/store/impl/InMemoryDOMDataStore.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.md.sal.dom.store.impl;
   9
  10 import static com.google.common.base.Preconditions.checkState;
  11
  12 import com.google.common.base.Optional;
  13 import com.google.common.base.Preconditions;
  14 import com.google.common.util.concurrent.FutureCallback;
  15 import com.google.common.util.concurrent.Futures;
  16 import com.google.common.util.concurrent.ListenableFuture;
  17 import com.google.common.util.concurrent.ListeningExecutorService;
  18 import com.google.common.util.concurrent.MoreExecutors;
  19
  20 import java.util.concurrent.Callable;
  21 import java.util.concurrent.ExecutorService;
  22 import java.util.concurrent.TimeUnit;
  23 import java.util.concurrent.atomic.AtomicLong;
  24
  25 import javax.annotation.concurrent.GuardedBy;
  26
  27 import org.opendaylight.controller.md.sal.common.api.data.AsyncDataBroker.DataChangeScope;
  28 import org.opendaylight.controller.md.sal.common.api.data.AsyncDataChangeListener;
  29 import org.opendaylight.controller.md.sal.common.api.data.OptimisticLockFailedException;
  30 import org.opendaylight.controller.md.sal.common.api.data.TransactionCommitFailedException;
  31 import org.opendaylight.controller.md.sal.dom.store.impl.SnapshotBackedWriteTransaction.TransactionReadyPrototype;
  32 import org.opendaylight.controller.md.sal.dom.store.impl.tree.ListenerTree;
  33 import org.opendaylight.controller.sal.core.spi.data.DOMStore;
  34 import org.opendaylight.controller.sal.core.spi.data.DOMStoreReadTransaction;
  35 import org.opendaylight.controller.sal.core.spi.data.DOMStoreReadWriteTransaction;
  36 import org.opendaylight.controller.sal.core.spi.data.DOMStoreThreePhaseCommitCohort;
  37 import org.opendaylight.controller.sal.core.spi.data.DOMStoreTransactionChain;
  38 import org.opendaylight.controller.sal.core.spi.data.DOMStoreWriteTransaction;
  39 import org.opendaylight.yangtools.concepts.AbstractListenerRegistration;
  40 import org.opendaylight.yangtools.concepts.Identifiable;
  41 import org.opendaylight.yangtools.concepts.ListenerRegistration;
  42 import org.opendaylight.yangtools.util.ExecutorServiceUtil;
  43 import org.opendaylight.yangtools.util.concurrent.QueuedNotificationManager;
  44 import org.opendaylight.yangtools.util.concurrent.QueuedNotificationManager.Invoker;
  45 import org.opendaylight.yangtools.yang.data.api.YangInstanceIdentifier;
  46 import org.opendaylight.yangtools.yang.data.api.schema.NormalizedNode;
  47 import org.opendaylight.yangtools.yang.data.api.schema.tree.ConflictingModificationAppliedException;
  48 import org.opendaylight.yangtools.yang.data.api.schema.tree.DataTree;
  49 import org.opendaylight.yangtools.yang.data.api.schema.tree.DataTreeCandidate;
  50 import org.opendaylight.yangtools.yang.data.api.schema.tree.DataTreeModification;
  51 import org.opendaylight.yangtools.yang.data.api.schema.tree.DataTreeSnapshot;
  52 import org.opendaylight.yangtools.yang.data.api.schema.tree.DataValidationFailedException;
  53 import org.opendaylight.yangtools.yang.data.impl.schema.tree.InMemoryDataTreeFactory;
  54 import org.opendaylight.yangtools.yang.model.api.SchemaContext;
  55 import org.opendaylight.yangtools.yang.model.api.SchemaContextListener;
  56 import org.slf4j.Logger;
  57 import org.slf4j.LoggerFactory;
  58
  59 /**
  60  * In-memory DOM Data Store
  61  *
  62  * Implementation of {@link DOMStore} which uses {@link DataTree} and other
  63  * classes such as {@link SnapshotBackedWriteTransaction}.
  64  * {@link SnapshotBackedReadTransaction} and {@link ResolveDataChangeEventsTask}
  65  * to implement {@link DOMStore} contract.
  66  *
  67  */
  68 public class InMemoryDOMDataStore implements DOMStore, Identifiable<String>, SchemaContextListener,
  69         TransactionReadyPrototype,AutoCloseable {
  70     private static final Logger LOG = LoggerFactory.getLogger(InMemoryDOMDataStore.class);
  71     private static final ListenableFuture<Void> SUCCESSFUL_FUTURE = Futures.immediateFuture(null);
  72
  73     private static final Invoker<DataChangeListenerRegistration<?>, DOMImmutableDataChangeEvent> DCL_NOTIFICATION_MGR_INVOKER =
  74             new Invoker<DataChangeListenerRegistration<?>, DOMImmutableDataChangeEvent>() {
  75                 @Override
  76                 public void invokeListener(final DataChangeListenerRegistration<?> listener,
  77                                            final DOMImmutableDataChangeEvent notification ) {
  78                     final AsyncDataChangeListener<YangInstanceIdentifier, NormalizedNode<?, ?>> inst = listener.getInstance();
  79                     if (inst != null) {
  80                         inst.onDataChanged(notification);
  81                     }
  82                 }
  83             };
  84
  85     private final DataTree dataTree = InMemoryDataTreeFactory.getInstance().create();
  86     private final ListenerTree listenerTree = ListenerTree.create();
  87     private final AtomicLong txCounter = new AtomicLong(0);
  88     private final ListeningExecutorService listeningExecutor;
  89
  90     private final QueuedNotificationManager<DataChangeListenerRegistration<?>, DOMImmutableDataChangeEvent> dataChangeListenerNotificationManager;
  91     private final ExecutorService dataChangeListenerExecutor;
  92
  93     private final ExecutorService domStoreExecutor;
  94
  95     private final String name;
  96
  97     private volatile AutoCloseable closeable;
  98
  99     public InMemoryDOMDataStore(final String name, final ExecutorService domStoreExecutor,
 100             final ExecutorService dataChangeListenerExecutor) {
 101         this(name, domStoreExecutor, dataChangeListenerExecutor,
 102              InMemoryDOMDataStoreConfigProperties.DEFAULT_MAX_DATA_CHANGE_LISTENER_QUEUE_SIZE);
 103     }
 104
 105     public InMemoryDOMDataStore(final String name, final ExecutorService domStoreExecutor,
 106             final ExecutorService dataChangeListenerExecutor, final int maxDataChangeListenerQueueSize) {
 107         this.name = Preconditions.checkNotNull(name);
 108         this.domStoreExecutor = Preconditions.checkNotNull(domStoreExecutor);
 109         this.listeningExecutor = MoreExecutors.listeningDecorator(this.domStoreExecutor);
 110         this.dataChangeListenerExecutor = Preconditions.checkNotNull(dataChangeListenerExecutor);
 111
 112         dataChangeListenerNotificationManager =
 113                 new QueuedNotificationManager<>(this.dataChangeListenerExecutor,
 114                         DCL_NOTIFICATION_MGR_INVOKER, maxDataChangeListenerQueueSize,
 115                         "DataChangeListenerQueueMgr");
 116     }
 117
 118     public void setCloseable(AutoCloseable closeable) {
 119         this.closeable = closeable;
 120     }
 121
 122     public QueuedNotificationManager<?, ?> getDataChangeListenerNotificationManager() {
 123         return dataChangeListenerNotificationManager;
 124     }
 125
 126     public ExecutorService getDomStoreExecutor() {
 127         return domStoreExecutor;
 128     }
 129
 130     @Override
 131     public final String getIdentifier() {
 132         return name;
 133     }
 134
 135     @Override
 136     public DOMStoreReadTransaction newReadOnlyTransaction() {
 137         return new SnapshotBackedReadTransaction(nextIdentifier(), dataTree.takeSnapshot());
 138     }
 139
 140     @Override
 141     public DOMStoreReadWriteTransaction newReadWriteTransaction() {
 142         return new SnapshotBackedReadWriteTransaction(nextIdentifier(), dataTree.takeSnapshot(), this);
 143     }
 144
 145     @Override
 146     public DOMStoreWriteTransaction newWriteOnlyTransaction() {
 147         return new SnapshotBackedWriteTransaction(nextIdentifier(), dataTree.takeSnapshot(), this);
 148     }
 149
 150     @Override
 151     public DOMStoreTransactionChain createTransactionChain() {
 152         return new DOMStoreTransactionChainImpl();
 153     }
 154
 155     @Override
 156     public synchronized void onGlobalContextUpdated(final SchemaContext ctx) {
 157         dataTree.setSchemaContext(ctx);
 158     }
 159
 160     @Override
 161     public void close() {
 162         ExecutorServiceUtil.tryGracefulShutdown(listeningExecutor, 30, TimeUnit.SECONDS);
 163         ExecutorServiceUtil.tryGracefulShutdown(dataChangeListenerExecutor, 30, TimeUnit.SECONDS);
 164
 165         if(closeable != null) {
 166             try {
 167                 closeable.close();
 168             } catch(Exception e) {
 169                 LOG.debug("Error closing instance", e);
 170             }
 171         }
 172     }
 173
 174     @Override
 175     public <L extends AsyncDataChangeListener<YangInstanceIdentifier, NormalizedNode<?, ?>>> ListenerRegistration<L> registerChangeListener(
 176             final YangInstanceIdentifier path, final L listener, final DataChangeScope scope) {
 177
 178         /*
 179          * Make sure commit is not occurring right now. Listener has to be
 180          * registered and its state capture enqueued at a consistent point.
 181          *
 182          * FIXME: improve this to read-write lock, such that multiple listener
 183          * registrations can occur simultaneously
 184          */
 185         final DataChangeListenerRegistration<L> reg;
 186         synchronized (this) {
 187             LOG.debug("{}: Registering data change listener {} for {}", name, listener, path);
 188
 189             reg = listenerTree.registerDataChangeListener(path, listener, scope);
 190
 191             Optional<NormalizedNode<?, ?>> currentState = dataTree.takeSnapshot().readNode(path);
 192             if (currentState.isPresent()) {
 193                 final NormalizedNode<?, ?> data = currentState.get();
 194
 195                 final DOMImmutableDataChangeEvent event = DOMImmutableDataChangeEvent.builder(DataChangeScope.BASE) //
 196                         .setAfter(data) //
 197                         .addCreated(path, data) //
 198                         .build();
 199
 200                 dataChangeListenerNotificationManager.submitNotification(reg, event);
 201             }
 202         }
 203
 204         return new AbstractListenerRegistration<L>(listener) {
 205             @Override
 206             protected void removeRegistration() {
 207                 synchronized (InMemoryDOMDataStore.this) {
 208                     reg.close();
 209                 }
 210             }
 211         };
 212     }
 213
 214     @Override
 215     public DOMStoreThreePhaseCommitCohort ready(final SnapshotBackedWriteTransaction writeTx) {
 216         LOG.debug("Tx: {} is submitted. Modifications: {}", writeTx.getIdentifier(), writeTx.getMutatedView());
 217         return new ThreePhaseCommitImpl(writeTx);
 218     }
 219
 220     private Object nextIdentifier() {
 221         return name + "-" + txCounter.getAndIncrement();
 222     }
 223
 224     private class DOMStoreTransactionChainImpl implements DOMStoreTransactionChain, TransactionReadyPrototype {
 225
 226         @GuardedBy("this")
 227         private SnapshotBackedWriteTransaction latestOutstandingTx;
 228
 229         private boolean chainFailed = false;
 230
 231         private void checkFailed() {
 232             Preconditions.checkState(!chainFailed, "Transaction chain is failed.");
 233         }
 234
 235         @Override
 236         public synchronized DOMStoreReadTransaction newReadOnlyTransaction() {
 237             final DataTreeSnapshot snapshot;
 238             checkFailed();
 239             if (latestOutstandingTx != null) {
 240                 checkState(latestOutstandingTx.isReady(), "Previous transaction in chain must be ready.");
 241                 snapshot = latestOutstandingTx.getMutatedView();
 242             } else {
 243                 snapshot = dataTree.takeSnapshot();
 244             }
 245             return new SnapshotBackedReadTransaction(nextIdentifier(), snapshot);
 246         }
 247
 248         @Override
 249         public synchronized DOMStoreReadWriteTransaction newReadWriteTransaction() {
 250             final DataTreeSnapshot snapshot;
 251             checkFailed();
 252             if (latestOutstandingTx != null) {
 253                 checkState(latestOutstandingTx.isReady(), "Previous transaction in chain must be ready.");
 254                 snapshot = latestOutstandingTx.getMutatedView();
 255             } else {
 256                 snapshot = dataTree.takeSnapshot();
 257             }
 258             final SnapshotBackedReadWriteTransaction ret = new SnapshotBackedReadWriteTransaction(nextIdentifier(),
 259                     snapshot, this);
 260             latestOutstandingTx = ret;
 261             return ret;
 262         }
 263
 264         @Override
 265         public synchronized DOMStoreWriteTransaction newWriteOnlyTransaction() {
 266             final DataTreeSnapshot snapshot;
 267             checkFailed();
 268             if (latestOutstandingTx != null) {
 269                 checkState(latestOutstandingTx.isReady(), "Previous transaction in chain must be ready.");
 270                 snapshot = latestOutstandingTx.getMutatedView();
 271             } else {
 272                 snapshot = dataTree.takeSnapshot();
 273             }
 274             final SnapshotBackedWriteTransaction ret = new SnapshotBackedWriteTransaction(nextIdentifier(), snapshot,
 275                     this);
 276             latestOutstandingTx = ret;
 277             return ret;
 278         }
 279
 280         @Override
 281         public DOMStoreThreePhaseCommitCohort ready(final SnapshotBackedWriteTransaction tx) {
 282             DOMStoreThreePhaseCommitCohort storeCohort = InMemoryDOMDataStore.this.ready(tx);
 283             return new ChainedTransactionCommitImpl(tx, storeCohort, this);
 284         }
 285
 286         @Override
 287         public void close() {
 288
 289             // FIXME: this call doesn't look right here - listeningExecutor is shared and owned
 290             // by the outer class.
 291             //listeningExecutor.shutdownNow();
 292         }
 293
 294         protected synchronized void onTransactionFailed(final SnapshotBackedWriteTransaction transaction,
 295                 final Throwable t) {
 296             chainFailed = true;
 297
 298         }
 299
 300         public synchronized void onTransactionCommited(final SnapshotBackedWriteTransaction transaction) {
 301             // If committed transaction is latestOutstandingTx we clear
 302             // latestOutstandingTx
 303             // field in order to base new transactions on Datastore Data Tree
 304             // directly.
 305             if (transaction.equals(latestOutstandingTx)) {
 306                 latestOutstandingTx = null;
 307             }
 308         }
 309
 310     }
 311
 312     private static class ChainedTransactionCommitImpl implements DOMStoreThreePhaseCommitCohort {
 313
 314         private final SnapshotBackedWriteTransaction transaction;
 315         private final DOMStoreThreePhaseCommitCohort delegate;
 316
 317         private final DOMStoreTransactionChainImpl txChain;
 318
 319         protected ChainedTransactionCommitImpl(final SnapshotBackedWriteTransaction transaction,
 320                 final DOMStoreThreePhaseCommitCohort delegate, final DOMStoreTransactionChainImpl txChain) {
 321             super();
 322             this.transaction = transaction;
 323             this.delegate = delegate;
 324             this.txChain = txChain;
 325         }
 326
 327         @Override
 328         public ListenableFuture<Boolean> canCommit() {
 329             return delegate.canCommit();
 330         }
 331
 332         @Override
 333         public ListenableFuture<Void> preCommit() {
 334             return delegate.preCommit();
 335         }
 336
 337         @Override
 338         public ListenableFuture<Void> abort() {
 339             return delegate.abort();
 340         }
 341
 342         @Override
 343         public ListenableFuture<Void> commit() {
 344             ListenableFuture<Void> commitFuture = delegate.commit();
 345             Futures.addCallback(commitFuture, new FutureCallback<Void>() {
 346                 @Override
 347                 public void onFailure(final Throwable t) {
 348                     txChain.onTransactionFailed(transaction, t);
 349                 }
 350
 351                 @Override
 352                 public void onSuccess(final Void result) {
 353                     txChain.onTransactionCommited(transaction);
 354                 }
 355
 356             });
 357             return commitFuture;
 358         }
 359
 360     }
 361
 362     private class ThreePhaseCommitImpl implements DOMStoreThreePhaseCommitCohort {
 363
 364         private final SnapshotBackedWriteTransaction transaction;
 365         private final DataTreeModification modification;
 366
 367         private ResolveDataChangeEventsTask listenerResolver;
 368         private DataTreeCandidate candidate;
 369
 370         public ThreePhaseCommitImpl(final SnapshotBackedWriteTransaction writeTransaction) {
 371             this.transaction = writeTransaction;
 372             this.modification = transaction.getMutatedView();
 373         }
 374
 375         @Override
 376         public ListenableFuture<Boolean> canCommit() {
 377             return listeningExecutor.submit(new Callable<Boolean>() {
 378                 @Override
 379                 public Boolean call() throws TransactionCommitFailedException {
 380                     try {
 381                         dataTree.validate(modification);
 382                         LOG.debug("Store Transaction: {} can be committed", transaction.getIdentifier());
 383                         return true;
 384                     } catch (ConflictingModificationAppliedException e) {
 385                         LOG.warn("Store Tx: {} Conflicting modification for {}.", transaction.getIdentifier(),
 386                                 e.getPath());
 387                         throw new OptimisticLockFailedException("Optimistic lock failed.",e);
 388                     } catch (DataValidationFailedException e) {
 389                         LOG.warn("Store Tx: {} Data Precondition failed for {}.", transaction.getIdentifier(),
 390                                 e.getPath(), e);
 391                         throw new TransactionCommitFailedException("Data did not pass validation.",e);
 392                     }
 393                 }
 394             });
 395         }
 396
 397         @Override
 398         public ListenableFuture<Void> preCommit() {
 399             return listeningExecutor.submit(new Callable<Void>() {
 400                 @Override
 401                 public Void call() {
 402                     candidate = dataTree.prepare(modification);
 403                     listenerResolver = ResolveDataChangeEventsTask.create(candidate, listenerTree);
 404                     return null;
 405                 }
 406             });
 407         }
 408
 409         @Override
 410         public ListenableFuture<Void> abort() {
 411             candidate = null;
 412             return SUCCESSFUL_FUTURE;
 413         }
 414
 415         @Override
 416         public ListenableFuture<Void> commit() {
 417             checkState(candidate != null, "Proposed subtree must be computed");
 418
 419             /*
 420              * The commit has to occur atomically with regard to listener
 421              * registrations.
 422              */
 423             synchronized (this) {
 424                 dataTree.commit(candidate);
 425                 listenerResolver.resolve(dataChangeListenerNotificationManager);
 426             }
 427
 428             return SUCCESSFUL_FUTURE;
 429         }
 430     }
 431 }