opendaylight/md-sal/sal-distributed-datastore/src/main/java/org/opendaylight/controller/cluster/databroker/actors/dds/RemoteProxyTransaction.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.Optional;
  11 import com.google.common.base.Preconditions;
  12 import com.google.common.util.concurrent.CheckedFuture;
  13 import com.google.common.util.concurrent.Futures;
  14 import com.google.common.util.concurrent.ListenableFuture;
  15 import com.google.common.util.concurrent.SettableFuture;
  16 import java.util.function.Consumer;
  17 import javax.annotation.Nullable;
  18 import org.opendaylight.controller.cluster.access.commands.AbstractReadTransactionRequest;
  19 import org.opendaylight.controller.cluster.access.commands.ExistsTransactionRequest;
  20 import org.opendaylight.controller.cluster.access.commands.ExistsTransactionSuccess;
  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.ReadTransactionRequest;
  25 import org.opendaylight.controller.cluster.access.commands.ReadTransactionSuccess;
  26 import org.opendaylight.controller.cluster.access.commands.TransactionAbortRequest;
  27 import org.opendaylight.controller.cluster.access.commands.TransactionDelete;
  28 import org.opendaylight.controller.cluster.access.commands.TransactionDoCommitRequest;
  29 import org.opendaylight.controller.cluster.access.commands.TransactionMerge;
  30 import org.opendaylight.controller.cluster.access.commands.TransactionModification;
  31 import org.opendaylight.controller.cluster.access.commands.TransactionPreCommitRequest;
  32 import org.opendaylight.controller.cluster.access.commands.TransactionRequest;
  33 import org.opendaylight.controller.cluster.access.commands.TransactionSuccess;
  34 import org.opendaylight.controller.cluster.access.commands.TransactionWrite;
  35 import org.opendaylight.controller.cluster.access.concepts.RequestFailure;
  36 import org.opendaylight.controller.cluster.access.concepts.Response;
  37 import org.opendaylight.controller.cluster.access.concepts.TransactionIdentifier;
  38 import org.opendaylight.mdsal.common.api.ReadFailedException;
  39 import org.opendaylight.yangtools.util.concurrent.MappingCheckedFuture;
  40 import org.opendaylight.yangtools.yang.data.api.YangInstanceIdentifier;
  41 import org.opendaylight.yangtools.yang.data.api.schema.NormalizedNode;
  42 import org.slf4j.Logger;
  43 import org.slf4j.LoggerFactory;
  44
  45 /**
  46  * An {@link AbstractProxyTransaction} for dispatching a transaction towards a shard leader whose location is currently
  47  * not known or is known to be not co-located with the client.
  48  *
  49  * <p>
  50  * It packages operations and sends them via the client actor queue to the shard leader. That queue is responsible for
  51  * maintaining any submitted operations until the leader is discovered.
  52  *
  53  * <p>
  54  * This class is not safe to access from multiple application threads, as is usual for transactions. Its internal state
  55  * transitions based on backend responses are thread-safe.
  56  *
  57  * @author Robert Varga
  58  */
  59 final class RemoteProxyTransaction extends AbstractProxyTransaction {
  60     private static final Logger LOG = LoggerFactory.getLogger(RemoteProxyTransaction.class);
  61
  62     // FIXME: make this tuneable
  63     private static final int REQUEST_MAX_MODIFICATIONS = 1000;
  64
  65     private final ModifyTransactionRequestBuilder builder;
  66     private final boolean sendReadyOnSeal;
  67     private final boolean snapshotOnly;
  68
  69     private boolean builderBusy;
  70
  71     private volatile Exception operationFailure;
  72
  73
  74     RemoteProxyTransaction(final ProxyHistory parent, final TransactionIdentifier identifier,
  75             final boolean snapshotOnly, final boolean sendReadyOnSeal) {
  76         super(parent);
  77         this.snapshotOnly = snapshotOnly;
  78         this.sendReadyOnSeal = sendReadyOnSeal;
  79         builder = new ModifyTransactionRequestBuilder(identifier, localActor());
  80     }
  81
  82     @Override
  83     boolean isSnapshotOnly() {
  84         return snapshotOnly;
  85     }
  86
  87     @Override
  88     public TransactionIdentifier getIdentifier() {
  89         return builder.getIdentifier();
  90     }
  91
  92     @Override
  93     void doDelete(final YangInstanceIdentifier path) {
  94         appendModification(new TransactionDelete(path));
  95     }
  96
  97     @Override
  98     void doMerge(final YangInstanceIdentifier path, final NormalizedNode<?, ?> data) {
  99         appendModification(new TransactionMerge(path, data));
 100     }
 101
 102     @Override
 103     void doWrite(final YangInstanceIdentifier path, final NormalizedNode<?, ?> data) {
 104         appendModification(new TransactionWrite(path, data));
 105     }
 106
 107     private <T> CheckedFuture<T, ReadFailedException> sendReadRequest(final AbstractReadTransactionRequest<?> request,
 108             final Consumer<Response<?, ?>> completer, final ListenableFuture<T> future) {
 109         // Check if a previous operation failed. If it has, do not bother sending anything and report a failure
 110         final Exception local = operationFailure;
 111         if (local != null) {
 112             return Futures.immediateFailedCheckedFuture(new ReadFailedException("Previous operation failed", local));
 113         }
 114
 115         // Make sure we send any modifications before issuing a read
 116         ensureFlushedBuider();
 117         sendRequest(request, completer);
 118         return MappingCheckedFuture.create(future, ReadFailedException.MAPPER);
 119     }
 120
 121     @Override
 122     CheckedFuture<Boolean, ReadFailedException> doExists(final YangInstanceIdentifier path) {
 123         final SettableFuture<Boolean> future = SettableFuture.create();
 124         return sendReadRequest(new ExistsTransactionRequest(getIdentifier(), nextSequence(), localActor(), path,
 125             isSnapshotOnly()), t -> completeExists(future, t), future);
 126     }
 127
 128     @Override
 129     CheckedFuture<Optional<NormalizedNode<?, ?>>, ReadFailedException> doRead(final YangInstanceIdentifier path) {
 130         final SettableFuture<Optional<NormalizedNode<?, ?>>> future = SettableFuture.create();
 131         return sendReadRequest(new ReadTransactionRequest(getIdentifier(), nextSequence(), localActor(), path,
 132             isSnapshotOnly()), t -> completeRead(future, t), future);
 133     }
 134
 135     @Override
 136     void doAbort() {
 137         ensureInitializedBuilder();
 138         builder.setAbort();
 139         flushBuilder();
 140     }
 141
 142     private void ensureInitializedBuilder() {
 143         if (!builderBusy) {
 144             builder.setSequence(nextSequence());
 145             builderBusy = true;
 146         }
 147     }
 148
 149     private void ensureFlushedBuider() {
 150         if (builderBusy) {
 151             flushBuilder();
 152         }
 153     }
 154
 155     private void flushBuilder() {
 156         final ModifyTransactionRequest request = builder.build();
 157         builderBusy = false;
 158
 159         sendModification(request);
 160     }
 161
 162     private void sendModification(final TransactionRequest<?> request) {
 163         sendRequest(request, response -> completeModify(request, response));
 164     }
 165
 166     @Override
 167     void handleForwardedRemoteRequest(final TransactionRequest<?> request,
 168             final @Nullable Consumer<Response<?, ?>> callback) {
 169         nextSequence();
 170
 171         if (callback == null) {
 172             sendModification(request);
 173             return;
 174         }
 175
 176         /*
 177          * FindBugs is utterly stupid, as it does not recognize the fact that we have checked for null
 178          * and reports NP_PARAMETER_MUST_BE_NONNULL_BUT_MARKED_AS_NULLABLE in the lambda below.
 179          */
 180         final Consumer<Response<?, ?>> findBugsIsStupid = callback;
 181
 182         // FIXME: do not use sendRequest() once we have throttling in place, as we have already waited the
 183         //        period required to get into the queue.
 184         sendRequest(request, response -> {
 185             findBugsIsStupid.accept(Preconditions.checkNotNull(response));
 186             completeModify(request, response);
 187         });
 188     }
 189
 190     private void appendModification(final TransactionModification modification) {
 191         if (operationFailure == null) {
 192             ensureInitializedBuilder();
 193
 194             builder.addModification(modification);
 195             if (builder.size() >= REQUEST_MAX_MODIFICATIONS) {
 196                 flushBuilder();
 197             }
 198         } else {
 199             LOG.debug("Transaction {} failed, not attempting further transactions", getIdentifier());
 200         }
 201     }
 202
 203     private void completeModify(final TransactionRequest<?> request, final Response<?, ?> response) {
 204         LOG.debug("Modification request {} completed with {}", request, response);
 205
 206         if (response instanceof TransactionSuccess) {
 207             // Happy path
 208             recordSuccessfulRequest(request);
 209         } else {
 210             recordFailedResponse(response);
 211         }
 212     }
 213
 214     private Exception recordFailedResponse(final Response<?, ?> response) {
 215         final Exception failure;
 216         if (response instanceof RequestFailure) {
 217             failure = ((RequestFailure<?, ?>) response).getCause();
 218         } else {
 219             LOG.warn("Unhandled response {}", response);
 220             failure = new IllegalArgumentException("Unhandled response " + response.getClass());
 221         }
 222
 223         if (operationFailure == null) {
 224             LOG.debug("Transaction {} failed", getIdentifier(), failure);
 225             operationFailure = failure;
 226         }
 227         return failure;
 228     }
 229
 230     private void failFuture(final SettableFuture<?> future, final Response<?, ?> response) {
 231         future.setException(recordFailedResponse(response));
 232     }
 233
 234     private void completeExists(final SettableFuture<Boolean> future, final Response<?, ?> response) {
 235         LOG.debug("Exists request completed with {}", response);
 236
 237         if (response instanceof ExistsTransactionSuccess) {
 238             future.set(((ExistsTransactionSuccess) response).getExists());
 239         } else {
 240             failFuture(future, response);
 241         }
 242
 243         recordFinishedRequest();
 244     }
 245
 246     private void completeRead(final SettableFuture<Optional<NormalizedNode<?, ?>>> future,
 247             final Response<?, ?> response) {
 248         LOG.debug("Read request completed with {}", response);
 249
 250         if (response instanceof ReadTransactionSuccess) {
 251             future.set(((ReadTransactionSuccess) response).getData());
 252         } else {
 253             failFuture(future, response);
 254         }
 255
 256         recordFinishedRequest();
 257     }
 258
 259     @Override
 260     ModifyTransactionRequest commitRequest(final boolean coordinated) {
 261         ensureInitializedBuilder();
 262         builder.setCommit(coordinated);
 263
 264         final ModifyTransactionRequest ret = builder.build();
 265         builderBusy = false;
 266         return ret;
 267     }
 268
 269     @Override
 270     void doSeal() {
 271         if (sendReadyOnSeal) {
 272             ensureInitializedBuilder();
 273             builder.setReady();
 274             flushBuilder();
 275         }
 276     }
 277
 278     @Override
 279     void flushState(final AbstractProxyTransaction successor) {
 280         if (builderBusy) {
 281             final ModifyTransactionRequest request = builder.build();
 282             builderBusy = false;
 283             successor.handleForwardedRemoteRequest(request, null);
 284         }
 285     }
 286
 287     @Override
 288     void forwardToRemote(final RemoteProxyTransaction successor, final TransactionRequest<?> request,
 289             final Consumer<Response<?, ?>> callback) {
 290         successor.handleForwardedRequest(request, callback);
 291     }
 292
 293     private void handleForwardedRequest(final TransactionRequest<?> request, final Consumer<Response<?, ?>> callback) {
 294         if (request instanceof ModifyTransactionRequest) {
 295             final ModifyTransactionRequest req = (ModifyTransactionRequest) request;
 296
 297             req.getModifications().forEach(this::appendModification);
 298
 299             final java.util.Optional<PersistenceProtocol> maybeProto = req.getPersistenceProtocol();
 300             if (maybeProto.isPresent()) {
 301                 ensureSealed();
 302
 303                 switch (maybeProto.get()) {
 304                     case ABORT:
 305                         sendAbort(callback);
 306                         break;
 307                     case SIMPLE:
 308                         sendRequest(commitRequest(false), callback);
 309                         break;
 310                     case THREE_PHASE:
 311                         sendRequest(commitRequest(true), callback);
 312                         break;
 313                     default:
 314                         throw new IllegalArgumentException("Unhandled protocol " + maybeProto.get());
 315                 }
 316             }
 317         } else if (request instanceof ReadTransactionRequest) {
 318             ensureFlushedBuider();
 319             sendRequest(new ReadTransactionRequest(getIdentifier(), nextSequence(), localActor(),
 320                 ((ReadTransactionRequest) request).getPath(), isSnapshotOnly()), callback);
 321         } else if (request instanceof ExistsTransactionRequest) {
 322             ensureFlushedBuider();
 323             sendRequest(new ExistsTransactionRequest(getIdentifier(), nextSequence(), localActor(),
 324                 ((ExistsTransactionRequest) request).getPath(), isSnapshotOnly()), callback);
 325         } else if (request instanceof TransactionPreCommitRequest) {
 326             ensureFlushedBuider();
 327             sendRequest(new TransactionPreCommitRequest(getIdentifier(), nextSequence(), localActor()), callback);
 328         } else if (request instanceof TransactionDoCommitRequest) {
 329             ensureFlushedBuider();
 330             sendRequest(new TransactionDoCommitRequest(getIdentifier(), nextSequence(), localActor()), callback);
 331         } else if (request instanceof TransactionAbortRequest) {
 332             ensureFlushedBuider();
 333             sendAbort(callback);
 334         } else {
 335             throw new IllegalArgumentException("Unhandled request {}" + request);
 336         }
 337     }
 338
 339     @Override
 340     void forwardToLocal(final LocalProxyTransaction successor, final TransactionRequest<?> request,
 341             final Consumer<Response<?, ?>> callback) {
 342         successor.handleForwardedRemoteRequest(request, callback);
 343     }
 344 }