package org.opendaylight.controller.cluster.datastore;
-import akka.actor.ActorPath;
+import akka.actor.ActorSelection;
+import akka.dispatch.OnComplete;
+import com.google.common.base.Preconditions;
+import com.google.common.base.Supplier;
+import com.google.common.collect.Lists;
+import com.google.common.util.concurrent.FutureCallback;
+import com.google.common.util.concurrent.Futures;
import com.google.common.util.concurrent.ListenableFuture;
-import org.opendaylight.controller.sal.core.spi.data.DOMStoreThreePhaseCommitCohort;
-
-import java.util.Collections;
+import com.google.common.util.concurrent.SettableFuture;
+import java.util.ArrayList;
+import java.util.Iterator;
import java.util.List;
+import java.util.concurrent.atomic.AtomicInteger;
+import org.opendaylight.controller.cluster.datastore.messages.AbortTransaction;
+import org.opendaylight.controller.cluster.datastore.messages.AbortTransactionReply;
+import org.opendaylight.controller.cluster.datastore.messages.CanCommitTransaction;
+import org.opendaylight.controller.cluster.datastore.messages.CanCommitTransactionReply;
+import org.opendaylight.controller.cluster.datastore.messages.CommitTransaction;
+import org.opendaylight.controller.cluster.datastore.messages.CommitTransactionReply;
+import org.opendaylight.controller.cluster.datastore.utils.ActorContext;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+import scala.concurrent.Future;
/**
* ThreePhaseCommitCohortProxy represents a set of remote cohort proxies
*/
-public class ThreePhaseCommitCohortProxy implements
- DOMStoreThreePhaseCommitCohort{
+public class ThreePhaseCommitCohortProxy extends AbstractThreePhaseCommitCohort<ActorSelection> {
+
+ private static final Logger LOG = LoggerFactory.getLogger(ThreePhaseCommitCohortProxy.class);
+
+ private static final MessageSupplier COMMIT_MESSAGE_SUPPLIER = new MessageSupplier() {
+ @Override
+ public Object newMessage(String transactionId, short version) {
+ return new CommitTransaction(transactionId, version).toSerializable();
+ }
+
+ @Override
+ public boolean isSerializedReplyType(Object reply) {
+ return CommitTransactionReply.isSerializedType(reply);
+ }
+ };
+
+ private static final MessageSupplier ABORT_MESSAGE_SUPPLIER = new MessageSupplier() {
+ @Override
+ public Object newMessage(String transactionId, short version) {
+ return new AbortTransaction(transactionId, version).toSerializable();
+ }
+
+ @Override
+ public boolean isSerializedReplyType(Object reply) {
+ return AbortTransactionReply.isSerializedType(reply);
+ }
+ };
+
+ private final ActorContext actorContext;
+ private final List<CohortInfo> cohorts;
+ private final SettableFuture<Void> cohortsResolvedFuture = SettableFuture.create();
+ private final String transactionId;
+ private volatile OperationCallback commitOperationCallback;
+
+ public ThreePhaseCommitCohortProxy(ActorContext actorContext, List<CohortInfo> cohorts, String transactionId) {
+ this.actorContext = actorContext;
+ this.cohorts = cohorts;
+ this.transactionId = transactionId;
+
+ if(cohorts.isEmpty()) {
+ cohortsResolvedFuture.set(null);
+ }
+ }
+
+ private ListenableFuture<Void> resolveCohorts() {
+ if(cohortsResolvedFuture.isDone()) {
+ return cohortsResolvedFuture;
+ }
+
+ final AtomicInteger completed = new AtomicInteger(cohorts.size());
+ for(final CohortInfo info: cohorts) {
+ info.getActorFuture().onComplete(new OnComplete<ActorSelection>() {
+ @Override
+ public void onComplete(Throwable failure, ActorSelection actor) {
+ synchronized(completed) {
+ boolean done = completed.decrementAndGet() == 0;
+ if(failure != null) {
+ LOG.debug("Tx {}: a cohort Future failed", transactionId, failure);
+ cohortsResolvedFuture.setException(failure);
+ } else if(!cohortsResolvedFuture.isDone()) {
+ LOG.debug("Tx {}: cohort actor {} resolved", transactionId, actor);
+
+ info.setResolvedActor(actor);
+ if(done) {
+ LOG.debug("Tx {}: successfully resolved all cohort actors", transactionId);
+ cohortsResolvedFuture.set(null);
+ }
+ }
+ }
+ }
+ }, actorContext.getClientDispatcher());
+ }
+
+ return cohortsResolvedFuture;
+ }
+
+ @Override
+ public ListenableFuture<Boolean> canCommit() {
+ LOG.debug("Tx {} canCommit", transactionId);
+
+ final SettableFuture<Boolean> returnFuture = SettableFuture.create();
+
+ // The first phase of canCommit is to gather the list of cohort actor paths that will
+ // participate in the commit. buildCohortPathsList combines the cohort path Futures into
+ // one Future which we wait on asynchronously here. The cohort actor paths are
+ // extracted from ReadyTransactionReply messages by the Futures that were obtained earlier
+ // and passed to us from upstream processing. If any one fails then we'll fail canCommit.
- private final List<ActorPath> cohortPaths;
+ Futures.addCallback(resolveCohorts(), new FutureCallback<Void>() {
+ @Override
+ public void onSuccess(Void notUsed) {
+ finishCanCommit(returnFuture);
+ }
- public ThreePhaseCommitCohortProxy(List<ActorPath> cohortPaths) {
+ @Override
+ public void onFailure(Throwable failure) {
+ returnFuture.setException(failure);
+ }
+ });
- this.cohortPaths = cohortPaths;
+ return returnFuture;
}
- @Override public ListenableFuture<Boolean> canCommit() {
- throw new UnsupportedOperationException("canCommit");
+ private void finishCanCommit(final SettableFuture<Boolean> returnFuture) {
+ LOG.debug("Tx {} finishCanCommit", transactionId);
+
+ // For empty transactions return immediately
+ if(cohorts.size() == 0){
+ LOG.debug("Tx {}: canCommit returning result true", transactionId);
+ returnFuture.set(Boolean.TRUE);
+ return;
+ }
+
+ commitOperationCallback = new TransactionRateLimitingCallback(actorContext);
+ commitOperationCallback.run();
+
+ final Iterator<CohortInfo> iterator = cohorts.iterator();
+
+ final OnComplete<Object> onComplete = new OnComplete<Object>() {
+ @Override
+ public void onComplete(Throwable failure, Object response) {
+ if (failure != null) {
+ LOG.debug("Tx {}: a canCommit cohort Future failed", transactionId, failure);
+
+ returnFuture.setException(failure);
+ commitOperationCallback.failure();
+ return;
+ }
+
+ // Only the first call to pause takes effect - subsequent calls before resume are no-ops. So
+ // this means we'll only time the first transaction canCommit which should be fine.
+ commitOperationCallback.pause();
+
+ boolean result = true;
+ if (CanCommitTransactionReply.isSerializedType(response)) {
+ CanCommitTransactionReply reply = CanCommitTransactionReply.fromSerializable(response);
+
+ LOG.debug("Tx {}: received {}", transactionId, response);
+
+ if (!reply.getCanCommit()) {
+ result = false;
+ }
+ } else {
+ LOG.error("Unexpected response type {}", response.getClass());
+ returnFuture.setException(new IllegalArgumentException(
+ String.format("Unexpected response type %s", response.getClass())));
+ return;
+ }
+
+ if(iterator.hasNext() && result) {
+ sendCanCommitTransaction(iterator.next(), this);
+ } else {
+ LOG.debug("Tx {}: canCommit returning result: {}", transactionId, result);
+ returnFuture.set(Boolean.valueOf(result));
+ }
+
+ }
+ };
+
+ sendCanCommitTransaction(iterator.next(), onComplete);
}
- @Override public ListenableFuture<Void> preCommit() {
- throw new UnsupportedOperationException("preCommit");
+ private void sendCanCommitTransaction(CohortInfo toCohortInfo, OnComplete<Object> onComplete) {
+ CanCommitTransaction message = new CanCommitTransaction(transactionId, toCohortInfo.getActorVersion());
+
+ if(LOG.isDebugEnabled()) {
+ LOG.debug("Tx {}: sending {} to {}", transactionId, message, toCohortInfo.getResolvedActor());
+ }
+
+ Future<Object> future = actorContext.executeOperationAsync(toCohortInfo.getResolvedActor(),
+ message.toSerializable(), actorContext.getTransactionCommitOperationTimeout());
+ future.onComplete(onComplete, actorContext.getClientDispatcher());
}
- @Override public ListenableFuture<Void> abort() {
- throw new UnsupportedOperationException("abort");
+ private Future<Iterable<Object>> invokeCohorts(MessageSupplier messageSupplier) {
+ List<Future<Object>> futureList = Lists.newArrayListWithCapacity(cohorts.size());
+ for(CohortInfo cohort : cohorts) {
+ Object message = messageSupplier.newMessage(transactionId, cohort.getActorVersion());
+
+ if(LOG.isDebugEnabled()) {
+ LOG.debug("Tx {}: Sending {} to cohort {}", transactionId, message , cohort);
+ }
+
+ futureList.add(actorContext.executeOperationAsync(cohort.getResolvedActor(), message,
+ actorContext.getTransactionCommitOperationTimeout()));
+ }
+
+ return akka.dispatch.Futures.sequence(futureList, actorContext.getClientDispatcher());
}
- @Override public ListenableFuture<Void> commit() {
- throw new UnsupportedOperationException("commit");
+ @Override
+ public ListenableFuture<Void> preCommit() {
+ // We don't need to do anything here - preCommit is done atomically with the commit phase
+ // by the shard.
+ return IMMEDIATE_VOID_SUCCESS;
+ }
+
+ @Override
+ public ListenableFuture<Void> abort() {
+ // Note - we pass false for propagateException. In the front-end data broker, this method
+ // is called when one of the 3 phases fails with an exception. We'd rather have that
+ // original exception propagated to the client. If our abort fails and we propagate the
+ // exception then that exception will supersede and suppress the original exception. But
+ // it's the original exception that is the root cause and of more interest to the client.
+
+ return voidOperation("abort", ABORT_MESSAGE_SUPPLIER,
+ AbortTransactionReply.class, false, OperationCallback.NO_OP_CALLBACK);
+ }
+
+ @Override
+ public ListenableFuture<Void> commit() {
+ OperationCallback operationCallback = commitOperationCallback != null ? commitOperationCallback :
+ OperationCallback.NO_OP_CALLBACK;
+
+ return voidOperation("commit", COMMIT_MESSAGE_SUPPLIER,
+ CommitTransactionReply.class, true, operationCallback);
+ }
+
+ private static boolean successfulFuture(ListenableFuture<Void> future) {
+ if(!future.isDone()) {
+ return false;
+ }
+
+ try {
+ future.get();
+ return true;
+ } catch(Exception e) {
+ return false;
+ }
+ }
+
+ private ListenableFuture<Void> voidOperation(final String operationName,
+ final MessageSupplier messageSupplier, final Class<?> expectedResponseClass,
+ final boolean propagateException, final OperationCallback callback) {
+ LOG.debug("Tx {} {}", transactionId, operationName);
+
+ final SettableFuture<Void> returnFuture = SettableFuture.create();
+
+ // The cohort actor list should already be built at this point by the canCommit phase but,
+ // if not for some reason, we'll try to build it here.
+
+ ListenableFuture<Void> future = resolveCohorts();
+ if(successfulFuture(future)) {
+ finishVoidOperation(operationName, messageSupplier, expectedResponseClass, propagateException,
+ returnFuture, callback);
+ } else {
+ Futures.addCallback(future, new FutureCallback<Void>() {
+ @Override
+ public void onSuccess(Void notUsed) {
+ finishVoidOperation(operationName, messageSupplier, expectedResponseClass,
+ propagateException, returnFuture, callback);
+ }
+
+ @Override
+ public void onFailure(Throwable failure) {
+ LOG.debug("Tx {}: a {} cohort path Future failed: {}", transactionId, operationName, failure);
+
+ if(propagateException) {
+ returnFuture.setException(failure);
+ } else {
+ returnFuture.set(null);
+ }
+ }
+ });
+ }
+
+ return returnFuture;
+ }
+
+ private void finishVoidOperation(final String operationName, MessageSupplier messageSupplier,
+ final Class<?> expectedResponseClass, final boolean propagateException,
+ final SettableFuture<Void> returnFuture, final OperationCallback callback) {
+ LOG.debug("Tx {} finish {}", transactionId, operationName);
+
+ callback.resume();
+
+ Future<Iterable<Object>> combinedFuture = invokeCohorts(messageSupplier);
+
+ combinedFuture.onComplete(new OnComplete<Iterable<Object>>() {
+ @Override
+ public void onComplete(Throwable failure, Iterable<Object> responses) throws Throwable {
+ Throwable exceptionToPropagate = failure;
+ if(exceptionToPropagate == null) {
+ for(Object response: responses) {
+ if(!response.getClass().equals(expectedResponseClass)) {
+ exceptionToPropagate = new IllegalArgumentException(
+ String.format("Unexpected response type %s", response.getClass()));
+ break;
+ }
+ }
+ }
+
+ if(exceptionToPropagate != null) {
+ LOG.debug("Tx {}: a {} cohort Future failed", transactionId, operationName, exceptionToPropagate);
+ if(propagateException) {
+ // We don't log the exception here to avoid redundant logging since we're
+ // propagating to the caller in MD-SAL core who will log it.
+ returnFuture.setException(exceptionToPropagate);
+ } else {
+ // Since the caller doesn't want us to propagate the exception we'll also
+ // not log it normally. But it's usually not good to totally silence
+ // exceptions so we'll log it to debug level.
+ returnFuture.set(null);
+ }
+
+ callback.failure();
+ } else {
+ LOG.debug("Tx {}: {} succeeded", transactionId, operationName);
+
+ returnFuture.set(null);
+
+ callback.success();
+ }
+ }
+ }, actorContext.getClientDispatcher());
+ }
+
+ @Override
+ List<Future<ActorSelection>> getCohortFutures() {
+ List<Future<ActorSelection>> cohortFutures = new ArrayList<>(cohorts.size());
+ for(CohortInfo info: cohorts) {
+ cohortFutures.add(info.getActorFuture());
+ }
+
+ return cohortFutures;
+ }
+
+ static class CohortInfo {
+ private final Future<ActorSelection> actorFuture;
+ private volatile ActorSelection resolvedActor;
+ private final Supplier<Short> actorVersionSupplier;
+
+ CohortInfo(Future<ActorSelection> actorFuture, Supplier<Short> actorVersionSupplier) {
+ this.actorFuture = actorFuture;
+ this.actorVersionSupplier = actorVersionSupplier;
+ }
+
+ Future<ActorSelection> getActorFuture() {
+ return actorFuture;
+ }
+
+ ActorSelection getResolvedActor() {
+ return resolvedActor;
+ }
+
+ void setResolvedActor(ActorSelection resolvedActor) {
+ this.resolvedActor = resolvedActor;
+ }
+
+ short getActorVersion() {
+ Preconditions.checkState(resolvedActor != null,
+ "getActorVersion cannot be called until the actor is resolved");
+ return actorVersionSupplier.get();
+ }
}
- public List<ActorPath> getCohortPaths() {
- return Collections.unmodifiableList(this.cohortPaths);
+ private interface MessageSupplier {
+ Object newMessage(String transactionId, short version);
+ boolean isSerializedReplyType(Object reply);
}
}