opendaylight/md-sal/sal-distributed-datastore/src/main/java/org/opendaylight/controller/cluster/datastore/DataTreeCohortActor.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
   9 package org.opendaylight.controller.cluster.datastore;
  10
  11 import akka.actor.ActorRef;
  12 import akka.actor.Props;
  13 import akka.actor.Status;
  14 import com.google.common.util.concurrent.FutureCallback;
  15 import com.google.common.util.concurrent.Futures;
  16 import com.google.common.util.concurrent.ListenableFuture;
  17 import com.google.common.util.concurrent.MoreExecutors;
  18 import java.util.Collection;
  19 import java.util.HashMap;
  20 import java.util.Map;
  21 import java.util.Objects;
  22 import java.util.concurrent.Executor;
  23 import javax.annotation.Nonnull;
  24 import javax.annotation.Nullable;
  25 import org.opendaylight.controller.cluster.access.concepts.TransactionIdentifier;
  26 import org.opendaylight.controller.cluster.common.actor.AbstractUntypedActor;
  27 import org.opendaylight.mdsal.common.api.PostCanCommitStep;
  28 import org.opendaylight.mdsal.common.api.PostPreCommitStep;
  29 import org.opendaylight.mdsal.common.api.ThreePhaseCommitStep;
  30 import org.opendaylight.mdsal.dom.api.DOMDataTreeCandidate;
  31 import org.opendaylight.mdsal.dom.api.DOMDataTreeCommitCohort;
  32 import org.opendaylight.yangtools.yang.data.api.YangInstanceIdentifier;
  33 import org.opendaylight.yangtools.yang.model.api.SchemaContext;
  34
  35 /**
  36  * Proxy actor which acts as a facade to the user-provided commit cohort. Responsible for
  37  * decapsulating DataTreeChanged messages and dispatching their context to the user.
  38  */
  39 final class DataTreeCohortActor extends AbstractUntypedActor {
  40     private final Idle idleState = new Idle();
  41     private final DOMDataTreeCommitCohort cohort;
  42     private final YangInstanceIdentifier registeredPath;
  43     private final Map<TransactionIdentifier, CohortBehaviour<?, ?>> currentStateMap = new HashMap<>();
  44
  45     private DataTreeCohortActor(final DOMDataTreeCommitCohort cohort, final YangInstanceIdentifier registeredPath) {
  46         this.cohort = Objects.requireNonNull(cohort);
  47         this.registeredPath = Objects.requireNonNull(registeredPath);
  48     }
  49
  50     @Override
  51     protected void handleReceive(final Object message) {
  52         if (!(message instanceof CommitProtocolCommand)) {
  53             unknownMessage(message);
  54             return;
  55         }
  56
  57         CommitProtocolCommand<?> command = (CommitProtocolCommand<?>)message;
  58         CohortBehaviour<?, ?> currentState = currentStateMap.computeIfAbsent(command.getTxId(), key -> idleState);
  59
  60         LOG.debug("handleReceive for cohort {} - currentState: {}, message: {}", cohort.getClass().getName(),
  61                 currentState, message);
  62
  63         currentState.handle(command);
  64     }
  65
  66     /**
  67      * Abstract message base for messages handled by {@link DataTreeCohortActor}.
  68      *
  69      * @param <R> Reply message type
  70      */
  71     abstract static class CommitProtocolCommand<R extends CommitReply> {
  72
  73         private final TransactionIdentifier txId;
  74
  75         final TransactionIdentifier getTxId() {
  76             return txId;
  77         }
  78
  79         protected CommitProtocolCommand(TransactionIdentifier txId) {
  80             this.txId = Objects.requireNonNull(txId);
  81         }
  82
  83         @Override
  84         public String toString() {
  85             return getClass().getSimpleName() + " [txId=" + txId + "]";
  86         }
  87     }
  88
  89     static final class CanCommit extends CommitProtocolCommand<Success> {
  90
  91         private final Collection<DOMDataTreeCandidate> candidates;
  92         private final ActorRef cohort;
  93         private final SchemaContext schema;
  94
  95         CanCommit(TransactionIdentifier txId, Collection<DOMDataTreeCandidate> candidates, SchemaContext schema,
  96                 ActorRef cohort) {
  97             super(txId);
  98             this.cohort = Objects.requireNonNull(cohort);
  99             this.candidates = Objects.requireNonNull(candidates);
 100             this.schema = Objects.requireNonNull(schema);
 101         }
 102
 103         Collection<DOMDataTreeCandidate> getCandidates() {
 104             return candidates;
 105         }
 106
 107         SchemaContext getSchema() {
 108             return schema;
 109         }
 110
 111         ActorRef getCohort() {
 112             return cohort;
 113         }
 114
 115         @Override
 116         public String toString() {
 117             return "CanCommit [txId=" + getTxId() + ", candidates=" + candidates + ", cohort=" + cohort  + "]";
 118         }
 119     }
 120
 121     abstract static class CommitReply {
 122
 123         private final ActorRef cohortRef;
 124         private final TransactionIdentifier txId;
 125
 126         protected CommitReply(ActorRef cohortRef, TransactionIdentifier txId) {
 127             this.cohortRef = Objects.requireNonNull(cohortRef);
 128             this.txId = Objects.requireNonNull(txId);
 129         }
 130
 131         ActorRef getCohort() {
 132             return cohortRef;
 133         }
 134
 135         final TransactionIdentifier getTxId() {
 136             return txId;
 137         }
 138
 139         @Override
 140         public String toString() {
 141             return getClass().getSimpleName() + " [txId=" + txId + ", cohortRef=" + cohortRef + "]";
 142         }
 143     }
 144
 145     static final class Success extends CommitReply {
 146
 147         Success(ActorRef cohortRef, TransactionIdentifier txId) {
 148             super(cohortRef, txId);
 149         }
 150     }
 151
 152     static final class PreCommit extends CommitProtocolCommand<Success> {
 153
 154         PreCommit(TransactionIdentifier txId) {
 155             super(txId);
 156         }
 157     }
 158
 159     static final class Abort extends CommitProtocolCommand<Success> {
 160
 161         Abort(TransactionIdentifier txId) {
 162             super(txId);
 163         }
 164     }
 165
 166     static final class Commit extends CommitProtocolCommand<Success> {
 167
 168         Commit(TransactionIdentifier txId) {
 169             super(txId);
 170         }
 171     }
 172
 173     private abstract class CohortBehaviour<M extends CommitProtocolCommand<?>, S extends ThreePhaseCommitStep> {
 174         private final Class<M> handledMessageType;
 175
 176         CohortBehaviour(Class<M> handledMessageType) {
 177             this.handledMessageType = Objects.requireNonNull(handledMessageType);
 178         }
 179
 180         void handle(CommitProtocolCommand<?> command) {
 181             if (handledMessageType.isInstance(command)) {
 182                 onMessage(command);
 183             } else if (command instanceof Abort) {
 184                 onAbort(((Abort)command).getTxId());
 185             } else {
 186                 getSender().tell(new Status.Failure(new IllegalArgumentException(String.format(
 187                         "Unexpected message %s in cohort behavior %s", command.getClass(),
 188                         getClass().getSimpleName()))), getSelf());
 189             }
 190         }
 191
 192         private void onMessage(CommitProtocolCommand<?> message) {
 193             final ActorRef sender = getSender();
 194             TransactionIdentifier txId = message.getTxId();
 195             ListenableFuture<S> future = process(handledMessageType.cast(message));
 196             Executor callbackExecutor = future.isDone() ? MoreExecutors.directExecutor()
 197                     : DataTreeCohortActor.this::executeInSelf;
 198             Futures.addCallback(future, new FutureCallback<S>() {
 199                 @Override
 200                 public void onSuccess(S nextStep) {
 201                     success(txId, sender, nextStep);
 202                 }
 203
 204                 @Override
 205                 public void onFailure(Throwable failure) {
 206                     failed(txId, sender, failure);
 207                 }
 208             }, callbackExecutor);
 209         }
 210
 211         private void failed(TransactionIdentifier txId, ActorRef sender, Throwable failure) {
 212             currentStateMap.remove(txId);
 213             sender.tell(new Status.Failure(failure), getSelf());
 214         }
 215
 216         private void success(TransactionIdentifier txId, ActorRef sender, S nextStep) {
 217             currentStateMap.computeIfPresent(txId, (key, behaviour) -> nextBehaviour(txId, nextStep));
 218             sender.tell(new Success(getSelf(), txId), getSelf());
 219         }
 220
 221         private void onAbort(TransactionIdentifier txId) {
 222             currentStateMap.remove(txId);
 223             final ActorRef sender = getSender();
 224             Futures.addCallback(abort(), new FutureCallback<Object>() {
 225                 @Override
 226                 public void onSuccess(Object noop) {
 227                     sender.tell(new Success(getSelf(), txId), getSelf());
 228                 }
 229
 230                 @Override
 231                 public void onFailure(Throwable failure) {
 232                     LOG.warn("Abort of transaction {} failed for cohort {}", txId, cohort, failure);
 233                     sender.tell(new Status.Failure(failure), getSelf());
 234                 }
 235             }, MoreExecutors.directExecutor());
 236         }
 237
 238         @Nullable
 239         abstract CohortBehaviour<?, ?> nextBehaviour(TransactionIdentifier txId, S nextStep);
 240
 241         @Nonnull
 242         abstract ListenableFuture<S> process(M command);
 243
 244         abstract ListenableFuture<?> abort();
 245
 246         @Override
 247         public String toString() {
 248             return getClass().getSimpleName();
 249         }
 250     }
 251
 252     private class Idle extends CohortBehaviour<CanCommit, PostCanCommitStep> {
 253         Idle() {
 254             super(CanCommit.class);
 255         }
 256
 257         @Override
 258         ListenableFuture<PostCanCommitStep> process(CanCommit message) {
 259             return cohort.canCommit(message.getTxId(), message.getSchema(), message.getCandidates());
 260         }
 261
 262         @Override
 263         CohortBehaviour<?, ?> nextBehaviour(TransactionIdentifier txId, PostCanCommitStep nextStep) {
 264             return new PostCanCommit(txId, nextStep);
 265         }
 266
 267         @Override
 268         ListenableFuture<?> abort() {
 269             return ThreePhaseCommitStep.NOOP_ABORT_FUTURE;
 270         }
 271     }
 272
 273     private abstract class CohortStateWithStep<M extends CommitProtocolCommand<?>, S extends ThreePhaseCommitStep,
 274             N extends ThreePhaseCommitStep> extends CohortBehaviour<M, N> {
 275         private final S step;
 276         private final TransactionIdentifier txId;
 277
 278         CohortStateWithStep(Class<M> handledMessageType, TransactionIdentifier txId, S step) {
 279             super(handledMessageType);
 280             this.txId = Objects.requireNonNull(txId);
 281             this.step = Objects.requireNonNull(step);
 282         }
 283
 284         final S getStep() {
 285             return step;
 286         }
 287
 288         @Override
 289         ListenableFuture<?> abort() {
 290             return getStep().abort();
 291         }
 292
 293         @Override
 294         public String toString() {
 295             return getClass().getSimpleName() + " [txId=" + txId + ", step=" + step + "]";
 296         }
 297     }
 298
 299     private class PostCanCommit extends CohortStateWithStep<PreCommit, PostCanCommitStep, PostPreCommitStep> {
 300
 301         PostCanCommit(TransactionIdentifier txId, PostCanCommitStep nextStep) {
 302             super(PreCommit.class, txId, nextStep);
 303         }
 304
 305         @SuppressWarnings("unchecked")
 306         @Override
 307         ListenableFuture<PostPreCommitStep> process(PreCommit message) {
 308             return (ListenableFuture<PostPreCommitStep>) getStep().preCommit();
 309         }
 310
 311         @Override
 312         CohortBehaviour<?, ?> nextBehaviour(TransactionIdentifier txId, PostPreCommitStep nextStep) {
 313             return new PostPreCommit(txId, nextStep);
 314         }
 315
 316     }
 317
 318     private class PostPreCommit extends CohortStateWithStep<Commit, PostPreCommitStep, NoopThreePhaseCommitStep> {
 319
 320         PostPreCommit(TransactionIdentifier txId, PostPreCommitStep step) {
 321             super(Commit.class, txId, step);
 322         }
 323
 324         @SuppressWarnings("unchecked")
 325         @Override
 326         ListenableFuture<NoopThreePhaseCommitStep> process(Commit message) {
 327             return (ListenableFuture<NoopThreePhaseCommitStep>) getStep().commit();
 328         }
 329
 330         @Override
 331         CohortBehaviour<?, ?> nextBehaviour(TransactionIdentifier txId, NoopThreePhaseCommitStep nextStep) {
 332             return null;
 333         }
 334     }
 335
 336     private interface NoopThreePhaseCommitStep extends ThreePhaseCommitStep {
 337     }
 338
 339     static Props props(final DOMDataTreeCommitCohort cohort, final YangInstanceIdentifier registeredPath) {
 340         return Props.create(DataTreeCohortActor.class, cohort, registeredPath);
 341     }
 342 }