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