X-Git-Url: https://git.opendaylight.org/gerrit/gitweb?p=controller.git;a=blobdiff_plain;f=opendaylight%2Fmd-sal%2Fsal-distributed-datastore%2Fsrc%2Fmain%2Fjava%2Forg%2Fopendaylight%2Fcontroller%2Fcluster%2Fdatastore%2FTransactionProxy.java;h=a8b20c030e1dd34f274ce2e02b56669739824af3;hp=2f784dc9506540448be304a68856103a704b72bf;hb=2dc333588d0c15eb7f2df6223dcdcc15e05b077e;hpb=a6a97a57081df63432dde5a6b1613eb779b74d79 diff --git a/opendaylight/md-sal/sal-distributed-datastore/src/main/java/org/opendaylight/controller/cluster/datastore/TransactionProxy.java b/opendaylight/md-sal/sal-distributed-datastore/src/main/java/org/opendaylight/controller/cluster/datastore/TransactionProxy.java index 2f784dc950..a8b20c030e 100644 --- a/opendaylight/md-sal/sal-distributed-datastore/src/main/java/org/opendaylight/controller/cluster/datastore/TransactionProxy.java +++ b/opendaylight/md-sal/sal-distributed-datastore/src/main/java/org/opendaylight/controller/cluster/datastore/TransactionProxy.java @@ -10,11 +10,24 @@ package org.opendaylight.controller.cluster.datastore; import akka.actor.ActorPath; import akka.actor.ActorSelection; +import akka.dispatch.OnComplete; + +import com.google.common.annotations.VisibleForTesting; +import com.google.common.base.FinalizablePhantomReference; +import com.google.common.base.FinalizableReferenceQueue; import com.google.common.base.Optional; -import com.google.common.util.concurrent.ListenableFuture; -import com.google.common.util.concurrent.ListenableFutureTask; +import com.google.common.base.Preconditions; +import com.google.common.collect.Lists; +import com.google.common.util.concurrent.CheckedFuture; +import com.google.common.util.concurrent.Futures; +import com.google.common.util.concurrent.SettableFuture; + +import org.opendaylight.controller.cluster.datastore.identifiers.TransactionIdentifier; import org.opendaylight.controller.cluster.datastore.messages.CloseTransaction; import org.opendaylight.controller.cluster.datastore.messages.CreateTransaction; +import org.opendaylight.controller.cluster.datastore.messages.CreateTransactionReply; +import org.opendaylight.controller.cluster.datastore.messages.DataExists; +import org.opendaylight.controller.cluster.datastore.messages.DataExistsReply; import org.opendaylight.controller.cluster.datastore.messages.DeleteData; import org.opendaylight.controller.cluster.datastore.messages.MergeData; import org.opendaylight.controller.cluster.datastore.messages.ReadData; @@ -24,19 +37,25 @@ import org.opendaylight.controller.cluster.datastore.messages.ReadyTransactionRe import org.opendaylight.controller.cluster.datastore.messages.WriteData; import org.opendaylight.controller.cluster.datastore.shardstrategy.ShardStrategyFactory; import org.opendaylight.controller.cluster.datastore.utils.ActorContext; -import org.opendaylight.controller.protobuff.messages.transaction.ShardTransactionMessages.CreateTransactionReply; +import org.opendaylight.controller.md.sal.common.api.data.ReadFailedException; import org.opendaylight.controller.sal.core.spi.data.DOMStoreReadWriteTransaction; import org.opendaylight.controller.sal.core.spi.data.DOMStoreThreePhaseCommitCohort; -import org.opendaylight.yangtools.yang.data.api.InstanceIdentifier; +import org.opendaylight.yangtools.util.concurrent.MappingCheckedFuture; +import org.opendaylight.yangtools.yang.data.api.YangInstanceIdentifier; import org.opendaylight.yangtools.yang.data.api.schema.NormalizedNode; import org.opendaylight.yangtools.yang.model.api.SchemaContext; +import org.slf4j.Logger; +import org.slf4j.LoggerFactory; + +import scala.Function1; +import scala.concurrent.Future; +import scala.runtime.AbstractFunction1; -import java.util.ArrayList; import java.util.HashMap; import java.util.List; import java.util.Map; -import java.util.concurrent.Callable; -import java.util.concurrent.ExecutorService; +import java.util.concurrent.ConcurrentHashMap; +import java.util.concurrent.atomic.AtomicBoolean; import java.util.concurrent.atomic.AtomicLong; /** @@ -58,109 +77,239 @@ public class TransactionProxy implements DOMStoreReadWriteTransaction { READ_WRITE } + static Function1 SAME_FAILURE_TRANSFORMER = new AbstractFunction1< + Throwable, Throwable>() { + @Override + public Throwable apply(Throwable failure) { + return failure; + } + }; + private static final AtomicLong counter = new AtomicLong(); + private static final Logger + LOG = LoggerFactory.getLogger(TransactionProxy.class); + + + /** + * Used to enqueue the PhantomReferences for read-only TransactionProxy instances. The + * FinalizableReferenceQueue is safe to use statically in an OSGi environment as it uses some + * trickery to clean up its internal thread when the bundle is unloaded. + */ + private static final FinalizableReferenceQueue phantomReferenceQueue = + new FinalizableReferenceQueue(); + + /** + * This stores the TransactionProxyCleanupPhantomReference instances statically, This is + * necessary because PhantomReferences need a hard reference so they're not garbage collected. + * Once finalized, the TransactionProxyCleanupPhantomReference removes itself from this map + * and thus becomes eligible for garbage collection. + */ + private static final Map phantomReferenceCache = + new ConcurrentHashMap<>(); + + /** + * A PhantomReference that closes remote transactions for a TransactionProxy when it's + * garbage collected. This is used for read-only transactions as they're not explicitly closed + * by clients. So the only way to detect that a transaction is no longer in use and it's safe + * to clean up is when it's garbage collected. It's inexact as to when an instance will be GC'ed + * but TransactionProxy instances should generally be short-lived enough to avoid being moved + * to the old generation space and thus should be cleaned up in a timely manner as the GC + * runs on the young generation (eden, swap1...) space much more frequently. + */ + private static class TransactionProxyCleanupPhantomReference + extends FinalizablePhantomReference { + + private final List remoteTransactionActors; + private final AtomicBoolean remoteTransactionActorsMB; + private final ActorContext actorContext; + private final TransactionIdentifier identifier; + + protected TransactionProxyCleanupPhantomReference(TransactionProxy referent) { + super(referent, phantomReferenceQueue); + + // Note we need to cache the relevant fields from the TransactionProxy as we can't + // have a hard reference to the TransactionProxy instance itself. + + remoteTransactionActors = referent.remoteTransactionActors; + remoteTransactionActorsMB = referent.remoteTransactionActorsMB; + actorContext = referent.actorContext; + identifier = referent.identifier; + } + + @Override + public void finalizeReferent() { + LOG.trace("Cleaning up {} Tx actors for TransactionProxy {}", + remoteTransactionActors.size(), identifier); + + phantomReferenceCache.remove(this); + + // Access the memory barrier volatile to ensure all previous updates to the + // remoteTransactionActors list are visible to this thread. + + if(remoteTransactionActorsMB.get()) { + for(ActorSelection actor : remoteTransactionActors) { + LOG.trace("Sending CloseTransaction to {}", actor); + actorContext.sendRemoteOperationAsync(actor, + new CloseTransaction().toSerializable()); + } + } + } + } + + /** + * Stores the remote Tx actors for each requested data store path to be used by the + * PhantomReference to close the remote Tx's. This is only used for read-only Tx's. The + * remoteTransactionActorsMB volatile serves as a memory barrier to publish updates to the + * remoteTransactionActors list so they will be visible to the thread accessing the + * PhantomReference. + */ + private List remoteTransactionActors; + private AtomicBoolean remoteTransactionActorsMB; + + private final Map remoteTransactionPaths = new HashMap<>(); + private final TransactionType transactionType; private final ActorContext actorContext; - private final Map remoteTransactionPaths = new HashMap<>(); - private final String identifier; - private final ExecutorService executor; + private final TransactionIdentifier identifier; private final SchemaContext schemaContext; + private boolean inReadyState; + + public TransactionProxy(ActorContext actorContext, TransactionType transactionType) { + this.actorContext = Preconditions.checkNotNull(actorContext, + "actorContext should not be null"); + this.transactionType = Preconditions.checkNotNull(transactionType, + "transactionType should not be null"); + this.schemaContext = Preconditions.checkNotNull(actorContext.getSchemaContext(), + "schemaContext should not be null"); + + String memberName = actorContext.getCurrentMemberName(); + if(memberName == null){ + memberName = "UNKNOWN-MEMBER"; + } + + this.identifier = TransactionIdentifier.builder().memberName(memberName).counter( + counter.getAndIncrement()).build(); - public TransactionProxy( - ActorContext actorContext, - TransactionType transactionType, - ExecutorService executor, - SchemaContext schemaContext - ) { + if(transactionType == TransactionType.READ_ONLY) { + // Read-only Tx's aren't explicitly closed by the client so we create a PhantomReference + // to close the remote Tx's when this instance is no longer in use and is garbage + // collected. - this.identifier = "txn-" + counter.getAndIncrement(); - this.transactionType = transactionType; - this.actorContext = actorContext; - this.executor = executor; - this.schemaContext = schemaContext; + remoteTransactionActors = Lists.newArrayList(); + remoteTransactionActorsMB = new AtomicBoolean(); + TransactionProxyCleanupPhantomReference cleanup = + new TransactionProxyCleanupPhantomReference(this); + phantomReferenceCache.put(cleanup, cleanup); + } + + LOG.debug("Created txn {} of type {}", identifier, transactionType); + } + + @VisibleForTesting + List> getRecordedOperationFutures() { + List> recordedOperationFutures = Lists.newArrayList(); + for(TransactionContext transactionContext : remoteTransactionPaths.values()) { + recordedOperationFutures.addAll(transactionContext.getRecordedOperationFutures()); + } + return recordedOperationFutures; } @Override - public ListenableFuture>> read(final InstanceIdentifier path) { + public CheckedFuture>, ReadFailedException> read( + final YangInstanceIdentifier path) { + + Preconditions.checkState(transactionType != TransactionType.WRITE_ONLY, + "Read operation on write-only transaction is not allowed"); + + LOG.debug("Tx {} read {}", identifier, path); createTransactionIfMissing(actorContext, path); - final ActorSelection remoteTransaction = remoteTransactionFromIdentifier(path); + return transactionContext(path).readData(path); + } - Callable>> call = new Callable() { + @Override + public CheckedFuture exists(YangInstanceIdentifier path) { - @Override public Optional> call() throws Exception { - Object response = actorContext - .executeRemoteOperation(remoteTransaction, new ReadData(path).toSerializable(), - ActorContext.ASK_DURATION); - if(response.getClass().equals(ReadDataReply.SERIALIZABLE_CLASS)){ - ReadDataReply reply = ReadDataReply.fromSerializable(schemaContext,path, response); - if(reply.getNormalizedNode() == null){ - return Optional.absent(); - } - //FIXME : A cast should not be required here ??? - return (Optional>) Optional.of(reply.getNormalizedNode()); - } + Preconditions.checkState(transactionType != TransactionType.WRITE_ONLY, + "Exists operation on write-only transaction is not allowed"); - return Optional.absent(); - } - }; + LOG.debug("Tx {} exists {}", identifier, path); - ListenableFutureTask>> - future = ListenableFutureTask.create(call); + createTransactionIfMissing(actorContext, path); - executor.submit(future); + return transactionContext(path).dataExists(path); + } - return future; + private void checkModificationState() { + Preconditions.checkState(transactionType != TransactionType.READ_ONLY, + "Modification operation on read-only transaction is not allowed"); + Preconditions.checkState(!inReadyState, + "Transaction is sealed - further modifications are not allowed"); } @Override - public void write(InstanceIdentifier path, NormalizedNode data) { + public void write(YangInstanceIdentifier path, NormalizedNode data) { + + checkModificationState(); + + LOG.debug("Tx {} write {}", identifier, path); createTransactionIfMissing(actorContext, path); - final ActorSelection remoteTransaction = remoteTransactionFromIdentifier(path); - remoteTransaction.tell(new WriteData(path, data, schemaContext).toSerializable(), null); + transactionContext(path).writeData(path, data); } @Override - public void merge(InstanceIdentifier path, NormalizedNode data) { + public void merge(YangInstanceIdentifier path, NormalizedNode data) { + + checkModificationState(); + + LOG.debug("Tx {} merge {}", identifier, path); createTransactionIfMissing(actorContext, path); - final ActorSelection remoteTransaction = remoteTransactionFromIdentifier(path); - remoteTransaction.tell(new MergeData(path, data, schemaContext).toSerializable(), null); + transactionContext(path).mergeData(path, data); } @Override - public void delete(InstanceIdentifier path) { + public void delete(YangInstanceIdentifier path) { + + checkModificationState(); + + LOG.debug("Tx {} delete {}", identifier, path); createTransactionIfMissing(actorContext, path); - final ActorSelection remoteTransaction = remoteTransactionFromIdentifier(path); - remoteTransaction.tell(new DeleteData(path).toSerializable(), null); + transactionContext(path).deleteData(path); } @Override public DOMStoreThreePhaseCommitCohort ready() { - List cohortPaths = new ArrayList<>(); - for(ActorSelection remoteTransaction : remoteTransactionPaths.values()) { - Object result = actorContext.executeRemoteOperation(remoteTransaction, - new ReadyTransaction(), - ActorContext.ASK_DURATION - ); + checkModificationState(); - if(result instanceof ReadyTransactionReply){ - ReadyTransactionReply reply = (ReadyTransactionReply) result; - cohortPaths.add(reply.getCohortPath()); - } + inReadyState = true; + + LOG.debug("Tx {} Trying to get {} transactions ready for commit", identifier, + remoteTransactionPaths.size()); + + List> cohortPathFutures = Lists.newArrayList(); + + for(TransactionContext transactionContext : remoteTransactionPaths.values()) { + + LOG.debug("Tx {} Readying transaction for shard {}", identifier, + transactionContext.getShardName()); + + cohortPathFutures.add(transactionContext.readyTransaction()); } - return new ThreePhaseCommitCohortProxy(actorContext, cohortPaths, identifier, executor); + return new ThreePhaseCommitCohortProxy(actorContext, cohortPathFutures, + identifier.toString()); } @Override @@ -170,37 +319,456 @@ public class TransactionProxy implements DOMStoreReadWriteTransaction { @Override public void close() { - for(ActorSelection remoteTransaction : remoteTransactionPaths.values()) { - remoteTransaction.tell(new CloseTransaction(), null); + for(TransactionContext transactionContext : remoteTransactionPaths.values()) { + transactionContext.closeTransaction(); + } + + remoteTransactionPaths.clear(); + + if(transactionType == TransactionType.READ_ONLY) { + remoteTransactionActors.clear(); + remoteTransactionActorsMB.set(true); } } - private ActorSelection remoteTransactionFromIdentifier(InstanceIdentifier path){ + private TransactionContext transactionContext(YangInstanceIdentifier path){ String shardName = shardNameFromIdentifier(path); return remoteTransactionPaths.get(shardName); } - private String shardNameFromIdentifier(InstanceIdentifier path){ + private String shardNameFromIdentifier(YangInstanceIdentifier path){ return ShardStrategyFactory.getStrategy(path).findShard(path); } - private void createTransactionIfMissing(ActorContext actorContext, InstanceIdentifier path) { + private void createTransactionIfMissing(ActorContext actorContext, YangInstanceIdentifier path) { String shardName = ShardStrategyFactory.getStrategy(path).findShard(path); - ActorSelection actorSelection = + TransactionContext transactionContext = remoteTransactionPaths.get(shardName); - if(actorSelection != null){ + if(transactionContext != null){ // A transaction already exists with that shard return; } - Object response = actorContext.executeShardOperation(shardName, new CreateTransaction(identifier), ActorContext.ASK_DURATION); - if(response instanceof CreateTransactionReply){ - CreateTransactionReply reply = (CreateTransactionReply) response; - remoteTransactionPaths.put(shardName, actorContext.actorSelection(reply.getTransactionActorPath())); + try { + Object response = actorContext.executeShardOperation(shardName, + new CreateTransaction(identifier.toString(),this.transactionType.ordinal() ).toSerializable()); + if (response.getClass().equals(CreateTransactionReply.SERIALIZABLE_CLASS)) { + CreateTransactionReply reply = + CreateTransactionReply.fromSerializable(response); + + String transactionPath = reply.getTransactionPath(); + + LOG.debug("Tx {} Received transaction path = {}", identifier, transactionPath); + + ActorSelection transactionActor = actorContext.actorSelection(transactionPath); + + if(transactionType == TransactionType.READ_ONLY) { + // Add the actor to the remoteTransactionActors list for access by the + // cleanup PhantonReference. + remoteTransactionActors.add(transactionActor); + + // Write to the memory barrier volatile to publish the above update to the + // remoteTransactionActors list for thread visibility. + remoteTransactionActorsMB.set(true); + } + + transactionContext = new TransactionContextImpl(shardName, transactionPath, + transactionActor, identifier, actorContext, schemaContext); + + remoteTransactionPaths.put(shardName, transactionContext); + } else { + throw new IllegalArgumentException(String.format( + "Invalid reply type {} for CreateTransaction", response.getClass())); + } + } catch(Exception e){ + LOG.debug("Tx {} Creating NoOpTransaction because of : {}", identifier, e.getMessage()); + remoteTransactionPaths.put(shardName, new NoOpTransactionContext(shardName, e, identifier)); } } + private interface TransactionContext { + String getShardName(); + + void closeTransaction(); + + Future readyTransaction(); + + void writeData(YangInstanceIdentifier path, NormalizedNode data); + + void deleteData(YangInstanceIdentifier path); + + void mergeData(YangInstanceIdentifier path, NormalizedNode data); + + CheckedFuture>, ReadFailedException> readData( + final YangInstanceIdentifier path); + + CheckedFuture dataExists(YangInstanceIdentifier path); + + List> getRecordedOperationFutures(); + } + + private static abstract class AbstractTransactionContext implements TransactionContext { + + protected final TransactionIdentifier identifier; + protected final String shardName; + protected final List> recordedOperationFutures = Lists.newArrayList(); + + AbstractTransactionContext(String shardName, TransactionIdentifier identifier) { + this.shardName = shardName; + this.identifier = identifier; + } + + @Override + public String getShardName() { + return shardName; + } + + @Override + public List> getRecordedOperationFutures() { + return recordedOperationFutures; + } + } + private static class TransactionContextImpl extends AbstractTransactionContext { + private final Logger LOG = LoggerFactory.getLogger(TransactionContextImpl.class); + + private final ActorContext actorContext; + private final SchemaContext schemaContext; + private final String actorPath; + private final ActorSelection actor; + + private TransactionContextImpl(String shardName, String actorPath, + ActorSelection actor, TransactionIdentifier identifier, ActorContext actorContext, + SchemaContext schemaContext) { + super(shardName, identifier); + this.actorPath = actorPath; + this.actor = actor; + this.actorContext = actorContext; + this.schemaContext = schemaContext; + } + + private ActorSelection getActor() { + return actor; + } + + private String getResolvedCohortPath(String cohortPath) { + return actorContext.resolvePath(actorPath, cohortPath); + } + + @Override + public void closeTransaction() { + LOG.debug("Tx {} closeTransaction called", identifier); + actorContext.sendRemoteOperationAsync(getActor(), new CloseTransaction().toSerializable()); + } + + @Override + public Future readyTransaction() { + LOG.debug("Tx {} readyTransaction called with {} previous recorded operations pending", + identifier, recordedOperationFutures.size()); + + // Send the ReadyTransaction message to the Tx actor. + + final Future replyFuture = actorContext.executeRemoteOperationAsync(getActor(), + new ReadyTransaction().toSerializable()); + + // Combine all the previously recorded put/merge/delete operation reply Futures and the + // ReadyTransactionReply Future into one Future. If any one fails then the combined + // Future will fail. We need all prior operations and the ready operation to succeed + // in order to attempt commit. + + List> futureList = + Lists.newArrayListWithCapacity(recordedOperationFutures.size() + 1); + futureList.addAll(recordedOperationFutures); + futureList.add(replyFuture); + + Future> combinedFutures = akka.dispatch.Futures.sequence(futureList, + actorContext.getActorSystem().dispatcher()); + + // Transform the combined Future into a Future that returns the cohort actor path from + // the ReadyTransactionReply. That's the end result of the ready operation. + + return combinedFutures.transform(new AbstractFunction1, ActorPath>() { + @Override + public ActorPath apply(Iterable notUsed) { + + LOG.debug("Tx {} readyTransaction: pending recorded operations succeeded", + identifier); + + // At this point all the Futures succeeded and we need to extract the cohort + // actor path from the ReadyTransactionReply. For the recorded operations, they + // don't return any data so we're only interested that they completed + // successfully. We could be paranoid and verify the correct reply types but + // that really should never happen so it's not worth the overhead of + // de-serializing each reply. + + // Note the Future get call here won't block as it's complete. + Object serializedReadyReply = replyFuture.value().get().get(); + if(serializedReadyReply.getClass().equals( + ReadyTransactionReply.SERIALIZABLE_CLASS)) { + ReadyTransactionReply reply = ReadyTransactionReply.fromSerializable( + actorContext.getActorSystem(), serializedReadyReply); + + String resolvedCohortPath = getResolvedCohortPath( + reply.getCohortPath().toString()); + + LOG.debug("Tx {} readyTransaction: resolved cohort path {}", + identifier, resolvedCohortPath); + + return actorContext.actorFor(resolvedCohortPath); + } else { + // Throwing an exception here will fail the Future. + + throw new IllegalArgumentException(String.format("Invalid reply type {}", + serializedReadyReply.getClass())); + } + } + }, SAME_FAILURE_TRANSFORMER, actorContext.getActorSystem().dispatcher()); + } + + @Override + public void deleteData(YangInstanceIdentifier path) { + LOG.debug("Tx {} deleteData called path = {}", identifier, path); + recordedOperationFutures.add(actorContext.executeRemoteOperationAsync(getActor(), + new DeleteData(path).toSerializable() )); + } + + @Override + public void mergeData(YangInstanceIdentifier path, NormalizedNode data) { + LOG.debug("Tx {} mergeData called path = {}", identifier, path); + recordedOperationFutures.add(actorContext.executeRemoteOperationAsync(getActor(), + new MergeData(path, data, schemaContext).toSerializable())); + } + + @Override + public void writeData(YangInstanceIdentifier path, NormalizedNode data) { + LOG.debug("Tx {} writeData called path = {}", identifier, path); + recordedOperationFutures.add(actorContext.executeRemoteOperationAsync(getActor(), + new WriteData(path, data, schemaContext).toSerializable())); + } + + @Override + public CheckedFuture>, ReadFailedException> readData( + final YangInstanceIdentifier path) { + + LOG.debug("Tx {} readData called path = {}", identifier, path); + + final SettableFuture>> returnFuture = SettableFuture.create(); + + // If there were any previous recorded put/merge/delete operation reply Futures then we + // must wait for them to successfully complete. This is necessary to honor the read + // uncommitted semantics of the public API contract. If any one fails then fail the read. + + if(recordedOperationFutures.isEmpty()) { + finishReadData(path, returnFuture); + } else { + LOG.debug("Tx {} readData: verifying {} previous recorded operations", + identifier, recordedOperationFutures.size()); + + // Note: we make a copy of recordedOperationFutures to be on the safe side in case + // Futures#sequence accesses the passed List on a different thread, as + // recordedOperationFutures is not synchronized. + + Future> combinedFutures = akka.dispatch.Futures.sequence( + Lists.newArrayList(recordedOperationFutures), + actorContext.getActorSystem().dispatcher()); + OnComplete> onComplete = new OnComplete>() { + @Override + public void onComplete(Throwable failure, Iterable notUsed) + throws Throwable { + if(failure != null) { + LOG.debug("Tx {} readData: a recorded operation failed: {}", + identifier, failure); + + returnFuture.setException(new ReadFailedException( + "The read could not be performed because a previous put, merge," + + "or delete operation failed", failure)); + } else { + finishReadData(path, returnFuture); + } + } + }; + + combinedFutures.onComplete(onComplete, actorContext.getActorSystem().dispatcher()); + } + + return MappingCheckedFuture.create(returnFuture, ReadFailedException.MAPPER); + } + + private void finishReadData(final YangInstanceIdentifier path, + final SettableFuture>> returnFuture) { + + LOG.debug("Tx {} finishReadData called path = {}", identifier, path); + + OnComplete onComplete = new OnComplete() { + @Override + public void onComplete(Throwable failure, Object readResponse) throws Throwable { + if(failure != null) { + LOG.debug("Tx {} read operation failed: {}", identifier, failure); + + returnFuture.setException(new ReadFailedException( + "Error reading data for path " + path, failure)); + + } else { + LOG.debug("Tx {} read operation succeeded", identifier, failure); + + if (readResponse.getClass().equals(ReadDataReply.SERIALIZABLE_CLASS)) { + ReadDataReply reply = ReadDataReply.fromSerializable(schemaContext, + path, readResponse); + if (reply.getNormalizedNode() == null) { + returnFuture.set(Optional.>absent()); + } else { + returnFuture.set(Optional.>of( + reply.getNormalizedNode())); + } + } else { + returnFuture.setException(new ReadFailedException( + "Invalid response reading data for path " + path)); + } + } + } + }; + + Future readFuture = actorContext.executeRemoteOperationAsync(getActor(), + new ReadData(path).toSerializable()); + readFuture.onComplete(onComplete, actorContext.getActorSystem().dispatcher()); + } + + @Override + public CheckedFuture dataExists( + final YangInstanceIdentifier path) { + + LOG.debug("Tx {} dataExists called path = {}", identifier, path); + + final SettableFuture returnFuture = SettableFuture.create(); + + // If there were any previous recorded put/merge/delete operation reply Futures then we + // must wait for them to successfully complete. This is necessary to honor the read + // uncommitted semantics of the public API contract. If any one fails then fail this + // request. + + if(recordedOperationFutures.isEmpty()) { + finishDataExists(path, returnFuture); + } else { + LOG.debug("Tx {} dataExists: verifying {} previous recorded operations", + identifier, recordedOperationFutures.size()); + + // Note: we make a copy of recordedOperationFutures to be on the safe side in case + // Futures#sequence accesses the passed List on a different thread, as + // recordedOperationFutures is not synchronized. + + Future> combinedFutures = akka.dispatch.Futures.sequence( + Lists.newArrayList(recordedOperationFutures), + actorContext.getActorSystem().dispatcher()); + OnComplete> onComplete = new OnComplete>() { + @Override + public void onComplete(Throwable failure, Iterable notUsed) + throws Throwable { + if(failure != null) { + LOG.debug("Tx {} dataExists: a recorded operation failed: {}", + identifier, failure); + + returnFuture.setException(new ReadFailedException( + "The data exists could not be performed because a previous " + + "put, merge, or delete operation failed", failure)); + } else { + finishDataExists(path, returnFuture); + } + } + }; + + combinedFutures.onComplete(onComplete, actorContext.getActorSystem().dispatcher()); + } + + return MappingCheckedFuture.create(returnFuture, ReadFailedException.MAPPER); + } + + private void finishDataExists(final YangInstanceIdentifier path, + final SettableFuture returnFuture) { + + LOG.debug("Tx {} finishDataExists called path = {}", identifier, path); + + OnComplete onComplete = new OnComplete() { + @Override + public void onComplete(Throwable failure, Object response) throws Throwable { + if(failure != null) { + LOG.debug("Tx {} dataExists operation failed: {}", identifier, failure); + + returnFuture.setException(new ReadFailedException( + "Error checking data exists for path " + path, failure)); + } else { + LOG.debug("Tx {} dataExists operation succeeded", identifier, failure); + + if (response.getClass().equals(DataExistsReply.SERIALIZABLE_CLASS)) { + returnFuture.set(Boolean.valueOf(DataExistsReply. + fromSerializable(response).exists())); + } else { + returnFuture.setException(new ReadFailedException( + "Invalid response checking exists for path " + path)); + } + } + } + }; + + Future future = actorContext.executeRemoteOperationAsync(getActor(), + new DataExists(path).toSerializable()); + future.onComplete(onComplete, actorContext.getActorSystem().dispatcher()); + } + } + + private static class NoOpTransactionContext extends AbstractTransactionContext { + + private final Logger LOG = LoggerFactory.getLogger(NoOpTransactionContext.class); + + private final Exception failure; + + public NoOpTransactionContext(String shardName, Exception failure, + TransactionIdentifier identifier){ + super(shardName, identifier); + this.failure = failure; + } + + @Override + public void closeTransaction() { + LOG.debug("NoOpTransactionContext {} closeTransaction called", identifier); + } + + @Override + public Future readyTransaction() { + LOG.debug("Tx {} readyTransaction called", identifier); + return akka.dispatch.Futures.failed(failure); + } + + @Override + public void deleteData(YangInstanceIdentifier path) { + LOG.debug("Tx {} deleteData called path = {}", identifier, path); + } + + @Override + public void mergeData(YangInstanceIdentifier path, NormalizedNode data) { + LOG.debug("Tx {} mergeData called path = {}", identifier, path); + } + + @Override + public void writeData(YangInstanceIdentifier path, NormalizedNode data) { + LOG.debug("Tx {} writeData called path = {}", identifier, path); + } + + @Override + public CheckedFuture>, ReadFailedException> readData( + YangInstanceIdentifier path) { + LOG.debug("Tx {} readData called path = {}", identifier, path); + return Futures.immediateFailedCheckedFuture(new ReadFailedException( + "Error reading data for path " + path, failure)); + } + + @Override + public CheckedFuture dataExists( + YangInstanceIdentifier path) { + LOG.debug("Tx {} dataExists called path = {}", identifier, path); + return Futures.immediateFailedCheckedFuture(new ReadFailedException( + "Error checking exists for path " + path, failure)); + } + } }