opendaylight/md-sal/sal-dom-broker/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.checkNotNull;
  11 import static com.google.common.base.Preconditions.checkState;
  12 import static org.opendaylight.controller.md.sal.dom.store.impl.StoreUtils.increase;
  13
  14 import java.util.concurrent.Callable;
  15 import java.util.concurrent.atomic.AtomicLong;
  16
  17 import org.opendaylight.controller.md.sal.common.api.data.AsyncDataBroker.DataChangeScope;
  18 import org.opendaylight.controller.md.sal.common.api.data.AsyncDataChangeListener;
  19 import org.opendaylight.controller.md.sal.dom.store.impl.tree.NodeModification;
  20 import org.opendaylight.controller.md.sal.dom.store.impl.tree.StoreMetadataNode;
  21 import org.opendaylight.controller.sal.core.spi.data.DOMStore;
  22 import org.opendaylight.controller.sal.core.spi.data.DOMStoreReadTransaction;
  23 import org.opendaylight.controller.sal.core.spi.data.DOMStoreReadWriteTransaction;
  24 import org.opendaylight.controller.sal.core.spi.data.DOMStoreThreePhaseCommitCohort;
  25 import org.opendaylight.controller.sal.core.spi.data.DOMStoreWriteTransaction;
  26 import org.opendaylight.yangtools.concepts.Identifiable;
  27 import org.opendaylight.yangtools.concepts.ListenerRegistration;
  28 import org.opendaylight.yangtools.yang.data.api.InstanceIdentifier;
  29 import org.opendaylight.yangtools.yang.data.api.InstanceIdentifier.PathArgument;
  30 import org.opendaylight.yangtools.yang.data.api.schema.NormalizedNode;
  31 import org.opendaylight.yangtools.yang.data.impl.schema.NormalizedNodeUtils;
  32 import org.opendaylight.yangtools.yang.model.api.SchemaContext;
  33 import org.opendaylight.yangtools.yang.model.api.SchemaContextListener;
  34 import org.slf4j.Logger;
  35 import org.slf4j.LoggerFactory;
  36
  37 import com.google.common.base.Optional;
  38 import com.google.common.primitives.UnsignedLong;
  39 import com.google.common.util.concurrent.Futures;
  40 import com.google.common.util.concurrent.ListenableFuture;
  41 import com.google.common.util.concurrent.ListeningExecutorService;
  42
  43 public class InMemoryDOMDataStore implements DOMStore, Identifiable<String>, SchemaContextListener {
  44
  45     private static final Logger LOG = LoggerFactory.getLogger(InMemoryDOMDataStore.class);
  46
  47     private final AtomicLong txCounter = new AtomicLong(0);
  48
  49     private DataAndMetadataSnapshot snapshot;
  50     private ModificationApplyOperation operation;
  51
  52     private final ListeningExecutorService executor;
  53     private final String name;
  54
  55     private SchemaContext schemaContext;
  56
  57     public InMemoryDOMDataStore(final String name, final ListeningExecutorService executor) {
  58         this.executor = executor;
  59         this.name = name;
  60         this.operation = new AllwaysFailOperation();
  61         this.snapshot = DataAndMetadataSnapshot.createEmpty();
  62     }
  63
  64     @Override
  65     public String getIdentifier() {
  66         return name;
  67     }
  68
  69     @Override
  70     public DOMStoreReadTransaction newReadOnlyTransaction() {
  71         return new SnapshotBackedReadTransaction(nextIdentifier(), snapshot);
  72     }
  73
  74     @Override
  75     public DOMStoreReadWriteTransaction newReadWriteTransaction() {
  76         return new SnapshotBackedReadWriteTransaction(nextIdentifier(), snapshot, this, operation);
  77     }
  78
  79     @Override
  80     public DOMStoreWriteTransaction newWriteOnlyTransaction() {
  81         return new SnaphostBackedWriteTransaction(nextIdentifier(), snapshot, this, operation);
  82     }
  83
  84     @Override
  85     public synchronized void onGlobalContextUpdated(final SchemaContext ctx) {
  86         operation = SchemaAwareApplyOperationRoot.from(ctx);
  87         schemaContext = ctx;
  88     }
  89
  90     @Override
  91     public <L extends AsyncDataChangeListener<InstanceIdentifier, NormalizedNode<?, ?>>> ListenerRegistration<L> registerChangeListener(
  92             final InstanceIdentifier path, final L listener, final DataChangeScope scope) {
  93         return null;
  94     }
  95
  96     private synchronized DOMStoreThreePhaseCommitCohort submit(
  97             final SnaphostBackedWriteTransaction snaphostBackedWriteTransaction) {
  98         return new ThreePhaseCommitImpl(snaphostBackedWriteTransaction);
  99     }
 100
 101     private Object nextIdentifier() {
 102         return name + "-" + txCounter.getAndIncrement();
 103     }
 104
 105     private static class SnapshotBackedReadTransaction implements DOMStoreReadTransaction {
 106
 107         private DataAndMetadataSnapshot stableSnapshot;
 108         private final Object identifier;
 109
 110         public SnapshotBackedReadTransaction(final Object identifier, final DataAndMetadataSnapshot snapshot) {
 111             this.identifier = identifier;
 112             this.stableSnapshot = snapshot;
 113         }
 114
 115         @Override
 116         public Object getIdentifier() {
 117             return identifier;
 118         }
 119
 120         @Override
 121         public void close() {
 122             stableSnapshot = null;
 123         }
 124
 125         @Override
 126         public ListenableFuture<Optional<NormalizedNode<?, ?>>> read(final InstanceIdentifier path) {
 127             checkNotNull(path, "Path must not be null.");
 128             checkState(stableSnapshot != null, "Transaction is closed");
 129             return Futures.immediateFuture(NormalizedNodeUtils.findNode(stableSnapshot.getDataTree(), path));
 130         }
 131
 132         @Override
 133         public String toString() {
 134             return "SnapshotBackedReadTransaction [id =" + identifier + "]";
 135         }
 136
 137     }
 138
 139     private static class SnaphostBackedWriteTransaction implements DOMStoreWriteTransaction {
 140
 141         private MutableDataTree mutableTree;
 142         private final Object identifier;
 143         private InMemoryDOMDataStore store;
 144
 145         private boolean ready = false;
 146
 147         public SnaphostBackedWriteTransaction(final Object identifier, final DataAndMetadataSnapshot snapshot,
 148                 final InMemoryDOMDataStore store, final ModificationApplyOperation applyOper) {
 149             this.identifier = identifier;
 150             mutableTree = MutableDataTree.from(snapshot, applyOper);
 151             this.store = store;
 152         }
 153
 154         @Override
 155         public Object getIdentifier() {
 156             return identifier;
 157         }
 158
 159         @Override
 160         public void close() {
 161             this.mutableTree = null;
 162             this.store = null;
 163         }
 164
 165         @Override
 166         public void write(final InstanceIdentifier path, final NormalizedNode<?, ?> data) {
 167             checkNotReady();
 168             mutableTree.write(path, data);
 169         }
 170
 171         @Override
 172         public void delete(final InstanceIdentifier path) {
 173             checkNotReady();
 174             mutableTree.delete(path);
 175         }
 176
 177         protected boolean isReady() {
 178             return ready;
 179         }
 180
 181         protected void checkNotReady() {
 182             checkState(!ready, "Transaction is ready. No further modifications allowed.");
 183         }
 184
 185         @Override
 186         public synchronized DOMStoreThreePhaseCommitCohort ready() {
 187             ready = true;
 188             LOG.debug("Store transaction: {} : Ready",getIdentifier());
 189             mutableTree.seal();
 190             return store.submit(this);
 191         }
 192
 193         protected MutableDataTree getMutatedView() {
 194             return mutableTree;
 195         }
 196
 197         @Override
 198         public String toString() {
 199             return "SnaphostBackedWriteTransaction [id=" + getIdentifier() + ", ready=" + isReady() + "]";
 200         }
 201
 202     }
 203
 204     private static class SnapshotBackedReadWriteTransaction extends SnaphostBackedWriteTransaction implements
 205             DOMStoreReadWriteTransaction {
 206
 207         protected SnapshotBackedReadWriteTransaction(final Object identifier, final DataAndMetadataSnapshot snapshot,
 208                 final InMemoryDOMDataStore store, final ModificationApplyOperation applyOper) {
 209             super(identifier, snapshot, store, applyOper);
 210         }
 211
 212         @Override
 213         public ListenableFuture<Optional<NormalizedNode<?, ?>>> read(final InstanceIdentifier path) {
 214             return Futures.immediateFuture(getMutatedView().read(path));
 215         }
 216
 217         @Override
 218         public String toString() {
 219             return "SnapshotBackedReadWriteTransaction [id=" + getIdentifier() + ", ready=" + isReady() + "]";
 220         }
 221
 222     }
 223
 224     private class ThreePhaseCommitImpl implements DOMStoreThreePhaseCommitCohort {
 225
 226         private final SnaphostBackedWriteTransaction transaction;
 227         private final NodeModification modification;
 228
 229         private DataAndMetadataSnapshot storeSnapshot;
 230         private Optional<StoreMetadataNode> proposedSubtree;
 231
 232         public ThreePhaseCommitImpl(final SnaphostBackedWriteTransaction writeTransaction) {
 233             this.transaction = writeTransaction;
 234             this.modification = transaction.getMutatedView().getRootModification();
 235         }
 236
 237         @Override
 238         public ListenableFuture<Boolean> canCommit() {
 239             final DataAndMetadataSnapshot snapshotCapture = snapshot;
 240             final ModificationApplyOperation snapshotOperation = operation;
 241
 242             return executor.submit(new Callable<Boolean>() {
 243
 244                 @Override
 245                 public Boolean call() throws Exception {
 246                     boolean applicable = snapshotOperation.isApplicable(modification, Optional.of(snapshotCapture.getMetadataTree()));
 247                     LOG.debug("Store Transcation: {} : canCommit : {}",transaction.getIdentifier(),applicable);
 248                     return applicable;
 249                 }
 250             });
 251         }
 252
 253         @Override
 254         public ListenableFuture<Void> preCommit() {
 255             storeSnapshot = snapshot;
 256             return executor.submit(new Callable<Void>() {
 257
 258                 @Override
 259                 public Void call() throws Exception {
 260                     StoreMetadataNode metadataTree = storeSnapshot.getMetadataTree();
 261                     proposedSubtree = operation.apply(modification, Optional.of(metadataTree),increase(metadataTree.getSubtreeVersion()));
 262                     return null;
 263                 }
 264             });
 265         }
 266
 267         @Override
 268         public ListenableFuture<Void> abort() {
 269             storeSnapshot = null;
 270             proposedSubtree = null;
 271             return Futures.<Void> immediateFuture(null);
 272         }
 273
 274         @Override
 275         public ListenableFuture<Void> commit() {
 276             checkState(proposedSubtree != null);
 277             checkState(storeSnapshot != null);
 278             // return ImmediateFuture<>;
 279             InMemoryDOMDataStore.this.commit(storeSnapshot, proposedSubtree);
 280             return Futures.<Void> immediateFuture(null);
 281         }
 282
 283     }
 284
 285     private synchronized void commit(final DataAndMetadataSnapshot storeSnapshot,
 286             final Optional<StoreMetadataNode> proposedSubtree) {
 287         //LOG.info("Updating Store snaphot.");
 288         checkState(snapshot == storeSnapshot, "Store snapshot and transaction snapshot differs");
 289         snapshot = DataAndMetadataSnapshot.builder().setMetadataTree(proposedSubtree.get())
 290                 .setSchemaContext(schemaContext).build();
 291     }
 292
 293     private class AllwaysFailOperation implements ModificationApplyOperation {
 294
 295         @Override
 296         public Optional<StoreMetadataNode> apply(final NodeModification modification,
 297                 final Optional<StoreMetadataNode> storeMeta,final UnsignedLong subtreeVersion) {
 298             throw new IllegalStateException("Schema Context is not available.");
 299         }
 300
 301         @Override
 302         public boolean isApplicable(final NodeModification modification, final Optional<StoreMetadataNode> storeMetadata) {
 303             throw new IllegalStateException("Schema Context is not available.");
 304         }
 305
 306         @Override
 307         public Optional<ModificationApplyOperation> getChild(final PathArgument child) {
 308             throw new IllegalStateException("Schema Context is not available.");
 309         }
 310
 311         @Override
 312         public void verifyStructure(final NodeModification modification) throws IllegalArgumentException {
 313             throw new IllegalStateException("Schema Context is not available.");
 314         }
 315
 316     }
 317 }