opendaylight/md-sal/sal-distributed-datastore/src/main/java/org/opendaylight/controller/cluster/databroker/actors/dds/LocalReadWriteProxyTransaction.java

   1 /*
   2  * Copyright (c) 2016 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.cluster.databroker.actors.dds;
   9
  10 import com.google.common.base.Preconditions;
  11 import com.google.common.base.Verify;
  12 import java.util.Optional;
  13 import java.util.function.BiConsumer;
  14 import java.util.function.Consumer;
  15 import java.util.function.Supplier;
  16 import javax.annotation.Nonnull;
  17 import javax.annotation.Nullable;
  18 import javax.annotation.concurrent.NotThreadSafe;
  19 import org.opendaylight.controller.cluster.access.commands.AbortLocalTransactionRequest;
  20 import org.opendaylight.controller.cluster.access.commands.AbstractLocalTransactionRequest;
  21 import org.opendaylight.controller.cluster.access.commands.CommitLocalTransactionRequest;
  22 import org.opendaylight.controller.cluster.access.commands.ModifyTransactionRequest;
  23 import org.opendaylight.controller.cluster.access.commands.ModifyTransactionRequestBuilder;
  24 import org.opendaylight.controller.cluster.access.commands.PersistenceProtocol;
  25 import org.opendaylight.controller.cluster.access.commands.TransactionAbortRequest;
  26 import org.opendaylight.controller.cluster.access.commands.TransactionDelete;
  27 import org.opendaylight.controller.cluster.access.commands.TransactionDoCommitRequest;
  28 import org.opendaylight.controller.cluster.access.commands.TransactionMerge;
  29 import org.opendaylight.controller.cluster.access.commands.TransactionModification;
  30 import org.opendaylight.controller.cluster.access.commands.TransactionPreCommitRequest;
  31 import org.opendaylight.controller.cluster.access.commands.TransactionRequest;
  32 import org.opendaylight.controller.cluster.access.commands.TransactionWrite;
  33 import org.opendaylight.controller.cluster.access.concepts.Response;
  34 import org.opendaylight.controller.cluster.access.concepts.TransactionIdentifier;
  35 import org.opendaylight.controller.cluster.datastore.util.AbstractDataTreeModificationCursor;
  36 import org.opendaylight.yangtools.yang.data.api.YangInstanceIdentifier;
  37 import org.opendaylight.yangtools.yang.data.api.YangInstanceIdentifier.PathArgument;
  38 import org.opendaylight.yangtools.yang.data.api.schema.NormalizedNode;
  39 import org.opendaylight.yangtools.yang.data.api.schema.tree.CursorAwareDataTreeModification;
  40 import org.opendaylight.yangtools.yang.data.api.schema.tree.CursorAwareDataTreeSnapshot;
  41 import org.opendaylight.yangtools.yang.data.api.schema.tree.DataTreeModification;
  42 import org.opendaylight.yangtools.yang.data.api.schema.tree.DataTreeModificationCursor;
  43 import org.opendaylight.yangtools.yang.data.api.schema.tree.DataTreeSnapshot;
  44 import org.slf4j.Logger;
  45 import org.slf4j.LoggerFactory;
  46
  47 /**
  48  * An {@link AbstractProxyTransaction} for dispatching a transaction towards a shard leader which is co-located with
  49  * the client instance.
  50  *
  51  * <p>
  52  * It requires a {@link DataTreeSnapshot}, which is used to instantiated a new {@link DataTreeModification}. Operations
  53  * are then performed on this modification and once the transaction is submitted, the modification is sent to the shard
  54  * leader.
  55  *
  56  * <p>
  57  * This class is not thread-safe as usual with transactions. Since it does not interact with the backend until the
  58  * transaction is submitted, at which point this class gets out of the picture, this is not a cause for concern.
  59  *
  60  * @author Robert Varga
  61  */
  62 @NotThreadSafe
  63 final class LocalReadWriteProxyTransaction extends LocalProxyTransaction {
  64     private static final Logger LOG = LoggerFactory.getLogger(LocalReadWriteProxyTransaction.class);
  65
  66     /**
  67      * This field needs to be accessed via {@link #getModification()}, which performs state checking to ensure
  68      * the modification can actually be accessed.
  69      */
  70     private final CursorAwareDataTreeModification modification;
  71
  72     private Supplier<? extends RuntimeException> closedException;
  73
  74     private CursorAwareDataTreeModification sealedModification;
  75
  76     /**
  77      * Recorded failure from previous operations. Normally we would want to propagate the error directly to the
  78      * offending call site, but that exposes inconsistency in behavior during initial connection, when we go through
  79      * {@link RemoteProxyTransaction}, which detects this sort of issues at canCommit/directCommit time on the backend.
  80      *
  81      * <p>
  82      * We therefore do not report incurred exceptions directly, but report them once the user attempts to commit
  83      * this transaction.
  84      */
  85     private Exception recordedFailure;
  86
  87     LocalReadWriteProxyTransaction(final ProxyHistory parent, final TransactionIdentifier identifier,
  88         final DataTreeSnapshot snapshot) {
  89         super(parent, identifier, false);
  90         this.modification = (CursorAwareDataTreeModification) snapshot.newModification();
  91     }
  92
  93     LocalReadWriteProxyTransaction(final ProxyHistory parent, final TransactionIdentifier identifier) {
  94         super(parent, identifier, true);
  95         // This is DONE transaction, this should never be touched
  96         this.modification = null;
  97     }
  98
  99     @Override
 100     boolean isSnapshotOnly() {
 101         return false;
 102     }
 103
 104     @Override
 105     CursorAwareDataTreeSnapshot readOnlyView() {
 106         return getModification();
 107     }
 108
 109     @Override
 110     @SuppressWarnings("checkstyle:IllegalCatch")
 111     void doDelete(final YangInstanceIdentifier path) {
 112         final CursorAwareDataTreeModification mod = getModification();
 113         if (recordedFailure != null) {
 114             LOG.debug("Transaction {} recorded failure, ignoring delete of {}", getIdentifier(), path);
 115             return;
 116         }
 117
 118         try {
 119             mod.delete(path);
 120         } catch (Exception e) {
 121             LOG.debug("Transaction {} delete on {} incurred failure, delaying it until commit", getIdentifier(), path,
 122                 e);
 123             recordedFailure = e;
 124         }
 125     }
 126
 127     @Override
 128     @SuppressWarnings("checkstyle:IllegalCatch")
 129     void doMerge(final YangInstanceIdentifier path, final NormalizedNode<?, ?> data) {
 130         final CursorAwareDataTreeModification mod = getModification();
 131         if (recordedFailure != null) {
 132             LOG.debug("Transaction {} recorded failure, ignoring merge to {}", getIdentifier(), path);
 133             return;
 134         }
 135
 136         try {
 137             mod.merge(path, data);
 138         } catch (Exception e) {
 139             LOG.debug("Transaction {} merge to {} incurred failure, delaying it until commit", getIdentifier(), path,
 140                 e);
 141             recordedFailure = e;
 142         }
 143     }
 144
 145     @Override
 146     @SuppressWarnings("checkstyle:IllegalCatch")
 147     void doWrite(final YangInstanceIdentifier path, final NormalizedNode<?, ?> data) {
 148         final CursorAwareDataTreeModification mod = getModification();
 149         if (recordedFailure != null) {
 150             LOG.debug("Transaction {} recorded failure, ignoring write to {}", getIdentifier(), path);
 151             return;
 152         }
 153
 154         try {
 155             mod.write(path, data);
 156         } catch (Exception e) {
 157             LOG.debug("Transaction {} write to {} incurred failure, delaying it until commit", getIdentifier(), path,
 158                 e);
 159             recordedFailure = e;
 160         }
 161     }
 162
 163     private RuntimeException abortedException() {
 164         return new IllegalStateException("Tracker " + getIdentifier() + " has been aborted");
 165     }
 166
 167     private RuntimeException submittedException() {
 168         return new IllegalStateException("Tracker " + getIdentifier() + " has been submitted");
 169     }
 170
 171     @Override
 172     CommitLocalTransactionRequest commitRequest(final boolean coordinated) {
 173         final CursorAwareDataTreeModification mod = getModification();
 174         final CommitLocalTransactionRequest ret = new CommitLocalTransactionRequest(getIdentifier(), nextSequence(),
 175             localActor(), mod, recordedFailure, coordinated);
 176         closedException = this::submittedException;
 177         return ret;
 178     }
 179
 180     private void sealModification() {
 181         Preconditions.checkState(sealedModification == null, "Transaction %s is already sealed", this);
 182         final CursorAwareDataTreeModification mod = getModification();
 183         mod.ready();
 184         sealedModification = mod;
 185     }
 186
 187     @Override
 188     void sealOnly() {
 189         sealModification();
 190         super.sealOnly();
 191     }
 192
 193     @Override
 194     boolean sealAndSend(final com.google.common.base.Optional<Long> enqueuedTicks) {
 195         sealModification();
 196         return super.sealAndSend(enqueuedTicks);
 197     }
 198
 199     @Override
 200     Optional<ModifyTransactionRequest> flushState() {
 201         final ModifyTransactionRequestBuilder b = new ModifyTransactionRequestBuilder(getIdentifier(), localActor());
 202         b.setSequence(0);
 203
 204         sealedModification.applyToCursor(new AbstractDataTreeModificationCursor() {
 205             @Override
 206             public void write(final PathArgument child, final NormalizedNode<?, ?> data) {
 207                 b.addModification(new TransactionWrite(current().node(child), data));
 208             }
 209
 210             @Override
 211             public void merge(final PathArgument child, final NormalizedNode<?, ?> data) {
 212                 b.addModification(new TransactionMerge(current().node(child), data));
 213             }
 214
 215             @Override
 216             public void delete(final PathArgument child) {
 217                 b.addModification(new TransactionDelete(current().node(child)));
 218             }
 219         });
 220
 221         return Optional.of(b.build());
 222     }
 223
 224     DataTreeSnapshot getSnapshot() {
 225         Preconditions.checkState(sealedModification != null, "Proxy %s is not sealed yet", getIdentifier());
 226         return sealedModification;
 227     }
 228
 229     @Override
 230     void applyForwardedModifyTransactionRequest(final ModifyTransactionRequest request,
 231             final @Nullable Consumer<Response<?, ?>> callback) {
 232         commonModifyTransactionRequest(request, callback, this::sendRequest);
 233     }
 234
 235     @Override
 236     void replayModifyTransactionRequest(final ModifyTransactionRequest request,
 237             final @Nullable Consumer<Response<?, ?>> callback, final long enqueuedTicks) {
 238         commonModifyTransactionRequest(request, callback, (req, cb) -> enqueueRequest(req, cb, enqueuedTicks));
 239     }
 240
 241     private void commonModifyTransactionRequest(final ModifyTransactionRequest request,
 242             final @Nullable Consumer<Response<?, ?>> callback,
 243             final BiConsumer<TransactionRequest<?>, Consumer<Response<?, ?>>> sendMethod) {
 244         for (final TransactionModification mod : request.getModifications()) {
 245             if (mod instanceof TransactionWrite) {
 246                 write(mod.getPath(), ((TransactionWrite)mod).getData());
 247             } else if (mod instanceof TransactionMerge) {
 248                 merge(mod.getPath(), ((TransactionMerge)mod).getData());
 249             } else if (mod instanceof TransactionDelete) {
 250                 delete(mod.getPath());
 251             } else {
 252                 throw new IllegalArgumentException("Unsupported modification " + mod);
 253             }
 254         }
 255
 256         final Optional<PersistenceProtocol> maybeProtocol = request.getPersistenceProtocol();
 257         if (maybeProtocol.isPresent()) {
 258             Verify.verify(callback != null, "Request %s has null callback", request);
 259             if (markSealed()) {
 260                 sealOnly();
 261             }
 262
 263             switch (maybeProtocol.get()) {
 264                 case ABORT:
 265                     sendMethod.accept(new AbortLocalTransactionRequest(getIdentifier(), localActor()), callback);
 266                     break;
 267                 case READY:
 268                     // No-op, as we have already issued a sealOnly() and we are not transmitting anything
 269                     break;
 270                 case SIMPLE:
 271                     sendMethod.accept(commitRequest(false), callback);
 272                     break;
 273                 case THREE_PHASE:
 274                     sendMethod.accept(commitRequest(true), callback);
 275                     break;
 276                 default:
 277                     throw new IllegalArgumentException("Unhandled protocol " + maybeProtocol.get());
 278             }
 279         }
 280     }
 281
 282     @Override
 283     void handleReplayedLocalRequest(final AbstractLocalTransactionRequest<?> request,
 284             final Consumer<Response<?, ?>> callback, final long now) {
 285         if (request instanceof CommitLocalTransactionRequest) {
 286             enqueueRequest(rebaseCommit((CommitLocalTransactionRequest)request), callback, now);
 287         } else {
 288             super.handleReplayedLocalRequest(request, callback, now);
 289         }
 290     }
 291
 292     @Override
 293     void handleReplayedRemoteRequest(final TransactionRequest<?> request,
 294             final @Nullable Consumer<Response<?, ?>> callback, final long enqueuedTicks) {
 295         LOG.debug("Applying replayed request {}", request);
 296
 297         if (request instanceof TransactionPreCommitRequest) {
 298             enqueueRequest(new TransactionPreCommitRequest(getIdentifier(), nextSequence(), localActor()), callback,
 299                 enqueuedTicks);
 300         } else if (request instanceof TransactionDoCommitRequest) {
 301             enqueueRequest(new TransactionDoCommitRequest(getIdentifier(), nextSequence(), localActor()), callback,
 302                 enqueuedTicks);
 303         } else if (request instanceof TransactionAbortRequest) {
 304             enqueueDoAbort(callback, enqueuedTicks);
 305         } else {
 306             super.handleReplayedRemoteRequest(request, callback, enqueuedTicks);
 307         }
 308     }
 309
 310     @Override
 311     void handleForwardedRemoteRequest(final TransactionRequest<?> request, final Consumer<Response<?, ?>> callback) {
 312         LOG.debug("Applying forwarded request {}", request);
 313
 314         if (request instanceof TransactionPreCommitRequest) {
 315             sendRequest(new TransactionPreCommitRequest(getIdentifier(), nextSequence(), localActor()), callback);
 316         } else if (request instanceof TransactionDoCommitRequest) {
 317             sendRequest(new TransactionDoCommitRequest(getIdentifier(), nextSequence(), localActor()), callback);
 318         } else if (request instanceof TransactionAbortRequest) {
 319             sendDoAbort(callback);
 320         } else {
 321             super.handleForwardedRemoteRequest(request, callback);
 322         }
 323     }
 324
 325     @Override
 326     void forwardToLocal(final LocalProxyTransaction successor, final TransactionRequest<?> request,
 327             final Consumer<Response<?, ?>> callback) {
 328         if (request instanceof CommitLocalTransactionRequest) {
 329             Verify.verify(successor instanceof LocalReadWriteProxyTransaction);
 330             ((LocalReadWriteProxyTransaction) successor).sendRebased((CommitLocalTransactionRequest)request, callback);
 331             LOG.debug("Forwarded request {} to successor {}", request, successor);
 332         } else {
 333             super.forwardToLocal(successor, request, callback);
 334         }
 335     }
 336
 337     @Override
 338     void sendAbort(final TransactionRequest<?> request, final Consumer<Response<?, ?>> callback) {
 339         super.sendAbort(request, callback);
 340         closedException = this::abortedException;
 341     }
 342
 343     @Override
 344     void enqueueAbort(final TransactionRequest<?> request, final Consumer<Response<?, ?>> callback,
 345             final long enqueuedTicks) {
 346         super.enqueueAbort(request, callback, enqueuedTicks);
 347         closedException = this::abortedException;
 348     }
 349
 350     private @Nonnull CursorAwareDataTreeModification getModification() {
 351         if (closedException != null) {
 352             throw closedException.get();
 353         }
 354
 355         return Preconditions.checkNotNull(modification, "Transaction %s is DONE", getIdentifier());
 356     }
 357
 358     private void sendRebased(final CommitLocalTransactionRequest request, final Consumer<Response<?, ?>> callback) {
 359         sendRequest(rebaseCommit(request), callback);
 360     }
 361
 362     private CommitLocalTransactionRequest rebaseCommit(final CommitLocalTransactionRequest request) {
 363         // Rebase old modification on new data tree.
 364         final CursorAwareDataTreeModification mod = getModification();
 365
 366         try (DataTreeModificationCursor cursor = mod.createCursor(YangInstanceIdentifier.EMPTY)) {
 367             request.getModification().applyToCursor(cursor);
 368         }
 369
 370         if (markSealed()) {
 371             sealOnly();
 372         }
 373
 374         return commitRequest(request.isCoordinated());
 375     }
 376 }