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 import com.google.common.base.Optional;
  12 import com.google.common.base.Preconditions;
  13 import com.google.common.util.concurrent.Futures;
  14 import com.google.common.util.concurrent.ListenableFuture;
  15 import java.util.concurrent.ExecutorService;
  16 import java.util.concurrent.TimeUnit;
  17 import java.util.concurrent.atomic.AtomicLong;
  18 import org.opendaylight.controller.md.sal.common.api.data.AsyncDataBroker.DataChangeScope;
  19 import org.opendaylight.controller.md.sal.common.api.data.AsyncDataChangeListener;
  20 import org.opendaylight.controller.md.sal.common.api.data.OptimisticLockFailedException;
  21 import org.opendaylight.controller.md.sal.common.api.data.TransactionCommitFailedException;
  22 import org.opendaylight.controller.md.sal.dom.api.DOMDataTreeChangeListener;
  23 import org.opendaylight.controller.md.sal.dom.store.impl.tree.ListenerTree;
  24 import org.opendaylight.controller.sal.core.spi.data.AbstractDOMStoreTransaction;
  25 import org.opendaylight.controller.sal.core.spi.data.DOMStore;
  26 import org.opendaylight.controller.sal.core.spi.data.DOMStoreReadTransaction;
  27 import org.opendaylight.controller.sal.core.spi.data.DOMStoreReadWriteTransaction;
  28 import org.opendaylight.controller.sal.core.spi.data.DOMStoreThreePhaseCommitCohort;
  29 import org.opendaylight.controller.sal.core.spi.data.DOMStoreTransactionChain;
  30 import org.opendaylight.controller.sal.core.spi.data.DOMStoreTreeChangePublisher;
  31 import org.opendaylight.controller.sal.core.spi.data.DOMStoreWriteTransaction;
  32 import org.opendaylight.controller.sal.core.spi.data.SnapshotBackedTransactions;
  33 import org.opendaylight.controller.sal.core.spi.data.SnapshotBackedWriteTransaction;
  34 import org.opendaylight.controller.sal.core.spi.data.SnapshotBackedWriteTransaction.TransactionReadyPrototype;
  35 import org.opendaylight.yangtools.concepts.AbstractListenerRegistration;
  36 import org.opendaylight.yangtools.concepts.Identifiable;
  37 import org.opendaylight.yangtools.concepts.ListenerRegistration;
  38 import org.opendaylight.yangtools.util.ExecutorServiceUtil;
  39 import org.opendaylight.yangtools.util.concurrent.QueuedNotificationManager;
  40 import org.opendaylight.yangtools.util.concurrent.QueuedNotificationManager.Invoker;
  41 import org.opendaylight.yangtools.yang.data.api.YangInstanceIdentifier;
  42 import org.opendaylight.yangtools.yang.data.api.schema.NormalizedNode;
  43 import org.opendaylight.yangtools.yang.data.api.schema.tree.ConflictingModificationAppliedException;
  44 import org.opendaylight.yangtools.yang.data.api.schema.tree.DataTree;
  45 import org.opendaylight.yangtools.yang.data.api.schema.tree.DataTreeCandidate;
  46 import org.opendaylight.yangtools.yang.data.api.schema.tree.DataTreeModification;
  47 import org.opendaylight.yangtools.yang.data.api.schema.tree.DataTreeSnapshot;
  48 import org.opendaylight.yangtools.yang.data.api.schema.tree.DataValidationFailedException;
  49 import org.opendaylight.yangtools.yang.data.impl.schema.tree.InMemoryDataTreeFactory;
  50 import org.opendaylight.yangtools.yang.model.api.SchemaContext;
  51 import org.opendaylight.yangtools.yang.model.api.SchemaContextListener;
  52 import org.slf4j.Logger;
  53 import org.slf4j.LoggerFactory;
  54
  55 /**
  56  * In-memory DOM Data Store
  57  *
  58  * Implementation of {@link DOMStore} which uses {@link DataTree} and other
  59  * classes such as {@link SnapshotBackedWriteTransaction}.
  60  * {@link org.opendaylight.controller.sal.core.spi.data.SnapshotBackedReadTransaction} and {@link ResolveDataChangeEventsTask}
  61  * to implement {@link DOMStore} contract.
  62  *
  63  */
  64 public class InMemoryDOMDataStore extends TransactionReadyPrototype<String> implements DOMStore, Identifiable<String>, SchemaContextListener, AutoCloseable, DOMStoreTreeChangePublisher {
  65     private static final Logger LOG = LoggerFactory.getLogger(InMemoryDOMDataStore.class);
  66     private static final ListenableFuture<Void> SUCCESSFUL_FUTURE = Futures.immediateFuture(null);
  67     private static final ListenableFuture<Boolean> CAN_COMMIT_FUTURE = Futures.immediateFuture(Boolean.TRUE);
  68
  69     private static final Invoker<DataChangeListenerRegistration<?>, DOMImmutableDataChangeEvent> DCL_NOTIFICATION_MGR_INVOKER =
  70             new Invoker<DataChangeListenerRegistration<?>, DOMImmutableDataChangeEvent>() {
  71                 @Override
  72                 public void invokeListener(final DataChangeListenerRegistration<?> listener,
  73                                            final DOMImmutableDataChangeEvent notification ) {
  74                     final AsyncDataChangeListener<YangInstanceIdentifier, NormalizedNode<?, ?>> inst = listener.getInstance();
  75                     if (inst != null) {
  76                         inst.onDataChanged(notification);
  77                     }
  78                 }
  79             };
  80
  81     private final DataTree dataTree = InMemoryDataTreeFactory.getInstance().create();
  82     private final ListenerTree listenerTree = ListenerTree.create();
  83     private final AtomicLong txCounter = new AtomicLong(0);
  84
  85     private final QueuedNotificationManager<DataChangeListenerRegistration<?>, DOMImmutableDataChangeEvent> dataChangeListenerNotificationManager;
  86     private final InMemoryDOMStoreTreeChangePublisher changePublisher;
  87     private final ExecutorService dataChangeListenerExecutor;
  88     private final boolean debugTransactions;
  89     private final String name;
  90
  91     private volatile AutoCloseable closeable;
  92
  93     public InMemoryDOMDataStore(final String name, final ExecutorService dataChangeListenerExecutor) {
  94         this(name, dataChangeListenerExecutor, InMemoryDOMDataStoreConfigProperties.DEFAULT_MAX_DATA_CHANGE_LISTENER_QUEUE_SIZE, false);
  95     }
  96
  97     public InMemoryDOMDataStore(final String name, final ExecutorService dataChangeListenerExecutor,
  98             final int maxDataChangeListenerQueueSize, final boolean debugTransactions) {
  99         this.name = Preconditions.checkNotNull(name);
 100         this.dataChangeListenerExecutor = Preconditions.checkNotNull(dataChangeListenerExecutor);
 101         this.debugTransactions = debugTransactions;
 102
 103         dataChangeListenerNotificationManager =
 104                 new QueuedNotificationManager<>(this.dataChangeListenerExecutor,
 105                         DCL_NOTIFICATION_MGR_INVOKER, maxDataChangeListenerQueueSize,
 106                         "DataChangeListenerQueueMgr");
 107         changePublisher = new InMemoryDOMStoreTreeChangePublisher(this.dataChangeListenerExecutor, maxDataChangeListenerQueueSize);
 108     }
 109
 110     public void setCloseable(final AutoCloseable closeable) {
 111         this.closeable = closeable;
 112     }
 113
 114     public QueuedNotificationManager<?, ?> getDataChangeListenerNotificationManager() {
 115         return dataChangeListenerNotificationManager;
 116     }
 117
 118     @Override
 119     public final String getIdentifier() {
 120         return name;
 121     }
 122
 123     @Override
 124     public DOMStoreReadTransaction newReadOnlyTransaction() {
 125         return SnapshotBackedTransactions.newReadTransaction(nextIdentifier(), debugTransactions, dataTree.takeSnapshot());
 126     }
 127
 128     @Override
 129     public DOMStoreReadWriteTransaction newReadWriteTransaction() {
 130         return SnapshotBackedTransactions.newReadWriteTransaction(nextIdentifier(), debugTransactions, dataTree.takeSnapshot(), this);
 131     }
 132
 133     @Override
 134     public DOMStoreWriteTransaction newWriteOnlyTransaction() {
 135         return SnapshotBackedTransactions.newWriteTransaction(nextIdentifier(), debugTransactions, dataTree.takeSnapshot(), this);
 136     }
 137
 138     @Override
 139     public DOMStoreTransactionChain createTransactionChain() {
 140         return new DOMStoreTransactionChainImpl(this);
 141     }
 142
 143     @Override
 144     public synchronized void onGlobalContextUpdated(final SchemaContext ctx) {
 145         dataTree.setSchemaContext(ctx);
 146     }
 147
 148     @Override
 149     public void close() {
 150         ExecutorServiceUtil.tryGracefulShutdown(dataChangeListenerExecutor, 30, TimeUnit.SECONDS);
 151
 152         if(closeable != null) {
 153             try {
 154                 closeable.close();
 155             } catch(Exception e) {
 156                 LOG.debug("Error closing instance", e);
 157             }
 158         }
 159     }
 160
 161     public final boolean getDebugTransactions() {
 162         return debugTransactions;
 163     }
 164
 165     final DataTreeSnapshot takeSnapshot() {
 166         return dataTree.takeSnapshot();
 167     }
 168
 169     @Override
 170     public <L extends AsyncDataChangeListener<YangInstanceIdentifier, NormalizedNode<?, ?>>> ListenerRegistration<L> registerChangeListener(
 171             final YangInstanceIdentifier path, final L listener, final DataChangeScope scope) {
 172
 173         /*
 174          * Make sure commit is not occurring right now. Listener has to be
 175          * registered and its state capture enqueued at a consistent point.
 176          *
 177          * FIXME: improve this to read-write lock, such that multiple listener
 178          * registrations can occur simultaneously
 179          */
 180         final DataChangeListenerRegistration<L> reg;
 181         synchronized (this) {
 182             LOG.debug("{}: Registering data change listener {} for {}", name, listener, path);
 183
 184             reg = listenerTree.registerDataChangeListener(path, listener, scope);
 185
 186             Optional<NormalizedNode<?, ?>> currentState = dataTree.takeSnapshot().readNode(path);
 187             if (currentState.isPresent()) {
 188                 final NormalizedNode<?, ?> data = currentState.get();
 189
 190                 final DOMImmutableDataChangeEvent event = DOMImmutableDataChangeEvent.builder(DataChangeScope.BASE) //
 191                         .setAfter(data) //
 192                         .addCreated(path, data) //
 193                         .build();
 194
 195                 dataChangeListenerNotificationManager.submitNotification(reg, event);
 196             }
 197         }
 198
 199         return new AbstractListenerRegistration<L>(listener) {
 200             @Override
 201             protected void removeRegistration() {
 202                 synchronized (InMemoryDOMDataStore.this) {
 203                     reg.close();
 204                 }
 205             }
 206         };
 207     }
 208
 209     @Override
 210     public synchronized <L extends DOMDataTreeChangeListener> ListenerRegistration<L> registerTreeChangeListener(final YangInstanceIdentifier treeId, final L listener) {
 211         /*
 212          * Make sure commit is not occurring right now. Listener has to be
 213          * registered and its state capture enqueued at a consistent point.
 214          */
 215         return changePublisher.registerTreeChangeListener(treeId, listener, dataTree.takeSnapshot());
 216     }
 217
 218     @Override
 219     protected void transactionAborted(final SnapshotBackedWriteTransaction<String> tx) {
 220         LOG.debug("Tx: {} is closed.", tx.getIdentifier());
 221     }
 222
 223     @Override
 224     protected DOMStoreThreePhaseCommitCohort transactionReady(final SnapshotBackedWriteTransaction<String> tx, final DataTreeModification tree) {
 225         LOG.debug("Tx: {} is submitted. Modifications: {}", tx.getIdentifier(), tree);
 226         return new ThreePhaseCommitImpl(tx, tree);
 227     }
 228
 229     String nextIdentifier() {
 230         return name + "-" + txCounter.getAndIncrement();
 231     }
 232
 233     private static void warnDebugContext(final AbstractDOMStoreTransaction<?> transaction) {
 234         final Throwable ctx = transaction.getDebugContext();
 235         if (ctx != null) {
 236             LOG.warn("Transaction {} has been allocated in the following context", transaction.getIdentifier(), ctx);
 237         }
 238     }
 239
 240     private final class ThreePhaseCommitImpl implements DOMStoreThreePhaseCommitCohort {
 241         private final SnapshotBackedWriteTransaction<String> transaction;
 242         private final DataTreeModification modification;
 243
 244         private ResolveDataChangeEventsTask listenerResolver;
 245         private DataTreeCandidate candidate;
 246
 247         public ThreePhaseCommitImpl(final SnapshotBackedWriteTransaction<String> writeTransaction, final DataTreeModification modification) {
 248             this.transaction = writeTransaction;
 249             this.modification = modification;
 250         }
 251
 252         @Override
 253         public ListenableFuture<Boolean> canCommit() {
 254             try {
 255                 dataTree.validate(modification);
 256                 LOG.debug("Store Transaction: {} can be committed", transaction.getIdentifier());
 257                 return CAN_COMMIT_FUTURE;
 258             } catch (ConflictingModificationAppliedException e) {
 259                 LOG.warn("Store Tx: {} Conflicting modification for {}.", transaction.getIdentifier(),
 260                         e.getPath());
 261                 warnDebugContext(transaction);
 262                 return Futures.immediateFailedFuture(new OptimisticLockFailedException("Optimistic lock failed.", e));
 263             } catch (DataValidationFailedException e) {
 264                 LOG.warn("Store Tx: {} Data Precondition failed for {}.", transaction.getIdentifier(),
 265                         e.getPath(), e);
 266                 warnDebugContext(transaction);
 267
 268                 // For debugging purposes, allow dumping of the modification. Coupled with the above
 269                 // precondition log, it should allow us to understand what went on.
 270                 LOG.trace("Store Tx: {} modifications: {} tree: {}", modification, dataTree);
 271
 272                 return Futures.immediateFailedFuture(new TransactionCommitFailedException("Data did not pass validation.", e));
 273             } catch (Exception e) {
 274                 LOG.warn("Unexpected failure in validation phase", e);
 275                 return Futures.immediateFailedFuture(e);
 276             }
 277         }
 278
 279         @Override
 280         public ListenableFuture<Void> preCommit() {
 281             try {
 282                 candidate = dataTree.prepare(modification);
 283                 listenerResolver = ResolveDataChangeEventsTask.create(candidate, listenerTree);
 284                 return SUCCESSFUL_FUTURE;
 285             } catch (Exception e) {
 286                 LOG.warn("Unexpected failure in pre-commit phase", e);
 287                 return Futures.immediateFailedFuture(e);
 288             }
 289         }
 290
 291         @Override
 292         public ListenableFuture<Void> abort() {
 293             candidate = null;
 294             return SUCCESSFUL_FUTURE;
 295         }
 296
 297         @Override
 298         public ListenableFuture<Void> commit() {
 299             checkState(candidate != null, "Proposed subtree must be computed");
 300
 301             /*
 302              * The commit has to occur atomically with regard to listener
 303              * registrations.
 304              */
 305             synchronized (InMemoryDOMDataStore.this) {
 306                 dataTree.commit(candidate);
 307                 changePublisher.publishChange(candidate);
 308                 listenerResolver.resolve(dataChangeListenerNotificationManager);
 309             }
 310
 311             return SUCCESSFUL_FUTURE;
 312         }
 313     }
 314 }