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