BUG-8618: introduce RaftActor.unpauseLeader()
[controller.git] / opendaylight / md-sal / sal-distributed-datastore / src / main / java / org / opendaylight / controller / cluster / datastore / Shard.java
index d5d129f22172cb392657de55360812014dbb7cae..10cef862fce2e42f731ebe01ff6775348c65476a 100644 (file)
@@ -12,19 +12,21 @@ import akka.actor.ActorRef;
 import akka.actor.ActorSelection;
 import akka.actor.Cancellable;
 import akka.actor.Props;
+import akka.actor.Status;
 import akka.actor.Status.Failure;
 import akka.serialization.Serialization;
 import com.google.common.annotations.VisibleForTesting;
 import com.google.common.base.Optional;
 import com.google.common.base.Preconditions;
 import com.google.common.base.Ticker;
+import com.google.common.base.Verify;
 import com.google.common.collect.ImmutableList;
+import com.google.common.collect.ImmutableMap;
 import com.google.common.collect.Range;
 import java.io.IOException;
 import java.util.Arrays;
 import java.util.Collection;
 import java.util.Collections;
-import java.util.HashMap;
 import java.util.Map;
 import java.util.concurrent.TimeUnit;
 import javax.annotation.Nonnull;
@@ -37,15 +39,19 @@ import org.opendaylight.controller.cluster.access.commands.NotLeaderException;
 import org.opendaylight.controller.cluster.access.commands.TransactionRequest;
 import org.opendaylight.controller.cluster.access.concepts.ClientIdentifier;
 import org.opendaylight.controller.cluster.access.concepts.FrontendIdentifier;
+import org.opendaylight.controller.cluster.access.concepts.LocalHistoryIdentifier;
 import org.opendaylight.controller.cluster.access.concepts.Request;
 import org.opendaylight.controller.cluster.access.concepts.RequestEnvelope;
 import org.opendaylight.controller.cluster.access.concepts.RequestException;
 import org.opendaylight.controller.cluster.access.concepts.RequestSuccess;
 import org.opendaylight.controller.cluster.access.concepts.RetiredGenerationException;
 import org.opendaylight.controller.cluster.access.concepts.RuntimeRequestException;
+import org.opendaylight.controller.cluster.access.concepts.SliceableMessage;
 import org.opendaylight.controller.cluster.access.concepts.TransactionIdentifier;
 import org.opendaylight.controller.cluster.access.concepts.UnsupportedRequestException;
 import org.opendaylight.controller.cluster.common.actor.CommonConfig;
+import org.opendaylight.controller.cluster.common.actor.Dispatchers;
+import org.opendaylight.controller.cluster.common.actor.Dispatchers.DispatcherType;
 import org.opendaylight.controller.cluster.common.actor.MessageTracker;
 import org.opendaylight.controller.cluster.common.actor.MessageTracker.Error;
 import org.opendaylight.controller.cluster.common.actor.MeteringBehavior;
@@ -61,21 +67,26 @@ import org.opendaylight.controller.cluster.datastore.messages.CloseTransactionCh
 import org.opendaylight.controller.cluster.datastore.messages.CommitTransaction;
 import org.opendaylight.controller.cluster.datastore.messages.CreateTransaction;
 import org.opendaylight.controller.cluster.datastore.messages.CreateTransactionReply;
-import org.opendaylight.controller.cluster.datastore.messages.DatastoreSnapshot;
-import org.opendaylight.controller.cluster.datastore.messages.DatastoreSnapshot.ShardSnapshot;
 import org.opendaylight.controller.cluster.datastore.messages.ForwardedReadyTransaction;
 import org.opendaylight.controller.cluster.datastore.messages.GetShardDataTree;
+import org.opendaylight.controller.cluster.datastore.messages.MakeLeaderLocal;
 import org.opendaylight.controller.cluster.datastore.messages.OnDemandShardState;
 import org.opendaylight.controller.cluster.datastore.messages.PeerAddressResolved;
+import org.opendaylight.controller.cluster.datastore.messages.PersistAbortTransactionPayload;
 import org.opendaylight.controller.cluster.datastore.messages.ReadyLocalTransaction;
 import org.opendaylight.controller.cluster.datastore.messages.RegisterChangeListener;
 import org.opendaylight.controller.cluster.datastore.messages.RegisterDataTreeChangeListener;
 import org.opendaylight.controller.cluster.datastore.messages.ShardLeaderStateChanged;
 import org.opendaylight.controller.cluster.datastore.messages.UpdateSchemaContext;
-import org.opendaylight.controller.cluster.datastore.utils.Dispatchers;
+import org.opendaylight.controller.cluster.datastore.persisted.AbortTransactionPayload;
+import org.opendaylight.controller.cluster.datastore.persisted.DatastoreSnapshot;
+import org.opendaylight.controller.cluster.datastore.persisted.DatastoreSnapshot.ShardSnapshot;
+import org.opendaylight.controller.cluster.messaging.MessageSlicer;
+import org.opendaylight.controller.cluster.messaging.SliceOptions;
 import org.opendaylight.controller.cluster.notifications.LeaderStateChanged;
 import org.opendaylight.controller.cluster.notifications.RegisterRoleChangeListener;
 import org.opendaylight.controller.cluster.notifications.RoleChangeNotifier;
+import org.opendaylight.controller.cluster.raft.LeadershipTransferFailedException;
 import org.opendaylight.controller.cluster.raft.RaftActor;
 import org.opendaylight.controller.cluster.raft.RaftActorRecoveryCohort;
 import org.opendaylight.controller.cluster.raft.RaftActorSnapshotCohort;
@@ -83,6 +94,7 @@ import org.opendaylight.controller.cluster.raft.RaftState;
 import org.opendaylight.controller.cluster.raft.base.messages.FollowerInitialSyncUpStatus;
 import org.opendaylight.controller.cluster.raft.client.messages.OnDemandRaftState;
 import org.opendaylight.controller.cluster.raft.messages.AppendEntriesReply;
+import org.opendaylight.controller.cluster.raft.messages.RequestLeadership;
 import org.opendaylight.controller.cluster.raft.messages.ServerRemoved;
 import org.opendaylight.controller.cluster.raft.protobuff.client.messages.Payload;
 import org.opendaylight.yangtools.concepts.Identifier;
@@ -90,6 +102,7 @@ import org.opendaylight.yangtools.yang.data.api.schema.tree.DataValidationFailed
 import org.opendaylight.yangtools.yang.data.api.schema.tree.TipProducingDataTree;
 import org.opendaylight.yangtools.yang.data.api.schema.tree.TreeType;
 import org.opendaylight.yangtools.yang.model.api.SchemaContext;
+import org.opendaylight.yangtools.yang.model.api.SchemaContextProvider;
 import scala.concurrent.duration.Duration;
 import scala.concurrent.duration.FiniteDuration;
 
@@ -117,6 +130,13 @@ public class Shard extends RaftActor {
         }
     };
 
+    static final Object RESUME_NEXT_PENDING_TRANSACTION = new Object() {
+        @Override
+        public String toString() {
+            return "resumeNextPendingTransaction";
+        }
+    };
+
     // FIXME: shard names should be encapsulated in their own class and this should be exposed as a constant.
     public static final String DEFAULT_NAME = "default";
 
@@ -163,8 +183,11 @@ public class Shard extends RaftActor {
 
     private final ShardTransactionMessageRetrySupport messageRetrySupport;
 
-    private final FrontendMetadata frontendMetadata = new FrontendMetadata();
-    private final Map<FrontendIdentifier, LeaderFrontendState> knownFrontends = new HashMap<>();
+    private final FrontendMetadata frontendMetadata;
+    private Map<FrontendIdentifier, LeaderFrontendState> knownFrontends = ImmutableMap.of();
+
+    private final MessageSlicer responseMessageSlicer;
+    private final Dispatchers dispatchers;
 
     protected Shard(final AbstractBuilder<?, ?> builder) {
         super(builder.getId().toString(), builder.getPeerAddresses(),
@@ -173,22 +196,23 @@ public class Shard extends RaftActor {
         this.name = builder.getId().toString();
         this.datastoreContext = builder.getDatastoreContext();
         this.restoreFromSnapshot = builder.getRestoreFromSnapshot();
+        this.frontendMetadata = new FrontendMetadata(name);
 
         setPersistence(datastoreContext.isPersistent());
 
         LOG.info("Shard created : {}, persistent : {}", name, datastoreContext.isPersistent());
 
         ShardDataTreeChangeListenerPublisherActorProxy treeChangeListenerPublisher =
-                new ShardDataTreeChangeListenerPublisherActorProxy(getContext(), name + "-DTCL-publisher");
+                new ShardDataTreeChangeListenerPublisherActorProxy(getContext(), name + "-DTCL-publisher", name);
         ShardDataChangeListenerPublisherActorProxy dataChangeListenerPublisher =
-                new ShardDataChangeListenerPublisherActorProxy(getContext(), name + "-DCL-publisher");
+                new ShardDataChangeListenerPublisherActorProxy(getContext(), name + "-DCL-publisher", name);
         if (builder.getDataTree() != null) {
             store = new ShardDataTree(this, builder.getSchemaContext(), builder.getDataTree(),
-                    treeChangeListenerPublisher, dataChangeListenerPublisher, name);
+                    treeChangeListenerPublisher, dataChangeListenerPublisher, name, frontendMetadata);
         } else {
             store = new ShardDataTree(this, builder.getSchemaContext(), builder.getTreeType(),
                     builder.getDatastoreContext().getStoreRoot(), treeChangeListenerPublisher,
-                    dataChangeListenerPublisher, name);
+                    dataChangeListenerPublisher, name, frontendMetadata);
         }
 
         shardMBean = ShardMBeanFactory.getShardStatsMBean(name, datastoreContext.getDataStoreMXBeanType(), this);
@@ -207,14 +231,20 @@ public class Shard extends RaftActor {
         appendEntriesReplyTracker = new MessageTracker(AppendEntriesReply.class,
                 getRaftActorContext().getConfigParams().getIsolatedCheckIntervalInMillis());
 
+        dispatchers = new Dispatchers(context().system().dispatchers());
         transactionActorFactory = new ShardTransactionActorFactory(store, datastoreContext,
-                new Dispatchers(context().system().dispatchers()).getDispatcherPath(
-                        Dispatchers.DispatcherType.Transaction), self(), getContext(), shardMBean);
+            dispatchers.getDispatcherPath(Dispatchers.DispatcherType.Transaction),
+                self(), getContext(), shardMBean, builder.getId().getShardName());
 
         snapshotCohort = ShardSnapshotCohort.create(getContext(), builder.getId().getMemberName(), store, LOG,
             this.name);
 
         messageRetrySupport = new ShardTransactionMessageRetrySupport(this);
+
+        responseMessageSlicer = MessageSlicer.builder().logContext(this.name)
+                .messageSliceSize(datastoreContext.getMaximumMessageSliceSize())
+                .fileBackedStreamFactory(getRaftActorContext().getFileBackedOutputStreamFactory())
+                .expireStateAfterInactivity(2, TimeUnit.MINUTES).build();
     }
 
     private void setTransactionCommitTimeout() {
@@ -256,33 +286,19 @@ public class Shard extends RaftActor {
         }
     }
 
-    @SuppressWarnings("checkstyle:IllegalCatch")
     @Override
     protected void handleNonRaftCommand(final Object message) {
-        try (final MessageTracker.Context context = appendEntriesReplyTracker.received(message)) {
+        try (MessageTracker.Context context = appendEntriesReplyTracker.received(message)) {
             final Optional<Error> maybeError = context.error();
             if (maybeError.isPresent()) {
                 LOG.trace("{} : AppendEntriesReply failed to arrive at the expected interval {}", persistenceId(),
                     maybeError.get());
             }
 
-            if (message instanceof RequestEnvelope) {
-                final long now = ticker().read();
-                final RequestEnvelope envelope = (RequestEnvelope)message;
+            store.resetTransactionBatch();
 
-                try {
-                    final RequestSuccess<?, ?> success = handleRequest(envelope, now);
-                    if (success != null) {
-                        envelope.sendSuccess(success, ticker().read() - now);
-                    }
-                } catch (RequestException e) {
-                    LOG.debug("{}: request {} failed", persistenceId(), envelope, e);
-                    envelope.sendFailure(e, ticker().read() - now);
-                } catch (Exception e) {
-                    LOG.debug("{}: request {} caused failure", persistenceId(), envelope, e);
-                    envelope.sendFailure(new RuntimeRequestException("Request failed to process", e),
-                        ticker().read() - now);
-                }
+            if (message instanceof RequestEnvelope) {
+                handleRequestEnvelope((RequestEnvelope)message);
             } else if (message instanceof ConnectClientRequest) {
                 handleConnectClient((ConnectClientRequest)message);
             } else if (CreateTransaction.isSerializedType(message)) {
@@ -331,12 +347,74 @@ public class Shard extends RaftActor {
             } else if (message instanceof DataTreeCohortActorRegistry.CohortRegistryCommand) {
                 store.processCohortRegistryCommand(getSender(),
                         (DataTreeCohortActorRegistry.CohortRegistryCommand) message);
-            } else {
+            } else if (message instanceof PersistAbortTransactionPayload) {
+                final TransactionIdentifier txId = ((PersistAbortTransactionPayload) message).getTransactionId();
+                persistPayload(txId, AbortTransactionPayload.create(txId), true);
+            } else if (message instanceof MakeLeaderLocal) {
+                onMakeLeaderLocal();
+            } else if (RESUME_NEXT_PENDING_TRANSACTION.equals(message)) {
+                store.resumeNextPendingTransaction();
+            } else if (!responseMessageSlicer.handleMessage(message)) {
                 super.handleNonRaftCommand(message);
             }
         }
     }
 
+    @SuppressWarnings("checkstyle:IllegalCatch")
+    private void handleRequestEnvelope(final RequestEnvelope envelope) {
+        final long now = ticker().read();
+        try {
+            final RequestSuccess<?, ?> success = handleRequest(envelope, now);
+            if (success != null) {
+                final long executionTimeNanos = ticker().read() - now;
+                if (success instanceof SliceableMessage) {
+                    dispatchers.getDispatcher(DispatcherType.Serialization).execute(() ->
+                        responseMessageSlicer.slice(SliceOptions.builder().identifier(success.getTarget())
+                            .message(envelope.newSuccessEnvelope(success, executionTimeNanos))
+                            .sendTo(envelope.getMessage().getReplyTo()).replyTo(self())
+                            .onFailureCallback(t -> {
+                                LOG.warn("Error slicing response {}", success, t);
+                            }).build()));
+                } else {
+                    envelope.sendSuccess(success, executionTimeNanos);
+                }
+            }
+        } catch (RequestException e) {
+            LOG.debug("{}: request {} failed", persistenceId(), envelope, e);
+            envelope.sendFailure(e, ticker().read() - now);
+        } catch (Exception e) {
+            LOG.debug("{}: request {} caused failure", persistenceId(), envelope, e);
+            envelope.sendFailure(new RuntimeRequestException("Request failed to process", e),
+                ticker().read() - now);
+        }
+    }
+
+    private void onMakeLeaderLocal() {
+        LOG.debug("{}: onMakeLeaderLocal received", persistenceId());
+        if (isLeader()) {
+            getSender().tell(new Status.Success(null), getSelf());
+            return;
+        }
+
+        final ActorSelection leader = getLeader();
+
+        if (leader == null) {
+            // Leader is not present. The cluster is most likely trying to
+            // elect a leader and we should let that run its normal course
+
+            // TODO we can wait for the election to complete and retry the
+            // request. We can also let the caller retry by sending a flag
+            // in the response indicating the request is "reTryable".
+            getSender().tell(new Failure(
+                    new LeadershipTransferFailedException("We cannot initiate leadership transfer to local node. "
+                            + "Currently there is no leader for " + persistenceId())),
+                    getSelf());
+            return;
+        }
+
+        leader.tell(new RequestLeadership(getId(), getSender()), getSelf());
+    }
+
     // Acquire our frontend tracking handle and verify generation matches
     private LeaderFrontendState getFrontend(final ClientIdentifier clientId) throws RequestException {
         final LeaderFrontendState existing = knownFrontends.get(clientId.getFrontendId());
@@ -380,7 +458,9 @@ public class Shard extends RaftActor {
     private void handleConnectClient(final ConnectClientRequest message) {
         try {
             if (!isLeader() || !isLeaderActive()) {
-                LOG.debug("{}: not currently leader, rejecting request {}", persistenceId(), message);
+                LOG.info("{}: not currently leader, rejecting request {}. isLeader: {}, isLeaderActive: {},"
+                                + "isLeadershipTransferInProgress: {}.",
+                        persistenceId(), message, isLeader(), isLeaderActive(), isLeadershipTransferInProgress());
                 throw new NotLeaderException(getSelf());
             }
 
@@ -399,7 +479,9 @@ public class Shard extends RaftActor {
             throws RequestException {
         // We are not the leader, hence we want to fail-fast.
         if (!isLeader() || !isLeaderActive()) {
-            LOG.debug("{}: not currently leader, rejecting request {}", persistenceId(), envelope);
+            LOG.info("{}: not currently leader, rejecting request {}. isLeader: {}, isLeaderActive: {},"
+                            + "isLeadershipTransferInProgress: {}.",
+                    persistenceId(), envelope, isLeader(), isLeaderActive(), isLeadershipTransferInProgress());
             throw new NotLeaderException(getSelf());
         }
 
@@ -413,7 +495,7 @@ public class Shard extends RaftActor {
             final ClientIdentifier clientId = lhReq.getTarget().getClientId();
             return getFrontend(clientId).handleLocalHistoryRequest(lhReq, envelope, now);
         } else {
-            LOG.debug("{}: rejecting unsupported request {}", persistenceId(), request);
+            LOG.warn("{}: rejecting unsupported request {}", persistenceId(), request);
             throw new UnsupportedRequestException(request);
         }
     }
@@ -453,13 +535,13 @@ public class Shard extends RaftActor {
     }
 
     // applyState() will be invoked once consensus is reached on the payload
-    void persistPayload(final TransactionIdentifier transactionId, final Payload payload, boolean batchHint) {
+    void persistPayload(final Identifier id, final Payload payload, final boolean batchHint) {
         boolean canSkipPayload = !hasFollowers() && !persistence().isRecoveryApplicable();
         if (canSkipPayload) {
-            applyState(self(), transactionId, payload);
+            applyState(self(), id, payload);
         } else {
             // We are faking the sender
-            persistData(self(), transactionId, payload, batchHint);
+            persistData(self(), id, payload, batchHint);
         }
     }
 
@@ -614,7 +696,7 @@ public class Shard extends RaftActor {
         doAbortTransaction(abort.getTransactionId(), getSender());
     }
 
-    void doAbortTransaction(final TransactionIdentifier transactionID, final ActorRef sender) {
+    void doAbortTransaction(final Identifier transactionID, final ActorRef sender) {
         commitCoordinator.handleAbort(transactionID, sender, this);
     }
 
@@ -630,7 +712,9 @@ public class Shard extends RaftActor {
     }
 
     private void closeTransactionChain(final CloseTransactionChain closeTransactionChain) {
-        store.closeTransactionChain(closeTransactionChain.getIdentifier());
+        final LocalHistoryIdentifier id = closeTransactionChain.getIdentifier();
+        store.closeTransactionChain(id, null);
+        store.purgeTransactionChain(id, null);
     }
 
     @SuppressWarnings("checkstyle:IllegalCatch")
@@ -730,7 +814,7 @@ public class Shard extends RaftActor {
                     persistenceId(), getId());
             }
 
-            store.closeAllTransactionChains();
+            store.purgeLeaderState();
         }
 
         if (hasLeader && !isIsolatedLeader()) {
@@ -742,8 +826,18 @@ public class Shard extends RaftActor {
     protected void onLeaderChanged(final String oldLeader, final String newLeader) {
         shardMBean.incrementLeadershipChangeCount();
 
-        boolean hasLeader = hasLeader();
-        if (hasLeader && !isLeader()) {
+        final boolean hasLeader = hasLeader();
+        if (!hasLeader) {
+            // No leader implies we are not the leader, lose frontend state if we have any. This also places
+            // an explicit guard so the map will not get modified accidentally.
+            if (!knownFrontends.isEmpty()) {
+                LOG.debug("{}: removing frontend state for {}", persistenceId(), knownFrontends.keySet());
+                knownFrontends = ImmutableMap.of();
+            }
+            return;
+        }
+
+        if (!isLeader()) {
             // Another leader was elected. If we were the previous leader and had pending transactions, convert
             // them to transaction messages and send to the new leader.
             ActorSelection leader = getLeader();
@@ -762,9 +856,13 @@ public class Shard extends RaftActor {
                 commitCoordinator.abortPendingTransactions("The transacton was aborted due to inflight leadership "
                         + "change and the leader address isn't available.", this);
             }
+        } else {
+            // We have become the leader, we need to reconstruct frontend state
+            knownFrontends = Verify.verifyNotNull(frontendMetadata.toLeaderState(this));
+            LOG.debug("{}: became leader with frontend state for {}", persistenceId(), knownFrontends.keySet());
         }
 
-        if (hasLeader && !isIsolatedLeader()) {
+        if (!isIsolatedLeader()) {
             messageRetrySupport.retryMessages();
         }
     }
@@ -785,6 +883,12 @@ public class Shard extends RaftActor {
         store.setRunOnPendingTransactionsComplete(operation);
     }
 
+    @Override
+    protected void unpauseLeader() {
+        LOG.debug("{}: In unpauseLeader", persistenceId());
+        store.setRunOnPendingTransactionsComplete(null);
+    }
+
     @Override
     protected OnDemandRaftState.AbstractBuilder<?> newOnDemandRaftStateBuilder() {
         return OnDemandShardState.newBuilder().treeChangeListenerActors(treeChangeSupport.getListenerActors())
@@ -825,7 +929,7 @@ public class Shard extends RaftActor {
         private ShardIdentifier id;
         private Map<String, String> peerAddresses = Collections.emptyMap();
         private DatastoreContext datastoreContext;
-        private SchemaContext schemaContext;
+        private SchemaContextProvider schemaContextProvider;
         private DatastoreSnapshot.ShardSnapshot restoreFromSnapshot;
         private TipProducingDataTree dataTree;
         private volatile boolean sealed;
@@ -861,9 +965,9 @@ public class Shard extends RaftActor {
             return self();
         }
 
-        public T schemaContext(final SchemaContext newSchemaContext) {
+        public T schemaContextProvider(final SchemaContextProvider schemaContextProvider) {
             checkSealed();
-            this.schemaContext = newSchemaContext;
+            this.schemaContextProvider = Preconditions.checkNotNull(schemaContextProvider);
             return self();
         }
 
@@ -892,7 +996,7 @@ public class Shard extends RaftActor {
         }
 
         public SchemaContext getSchemaContext() {
-            return schemaContext;
+            return Verify.verifyNotNull(schemaContextProvider.getSchemaContext());
         }
 
         public DatastoreSnapshot.ShardSnapshot getRestoreFromSnapshot() {
@@ -919,7 +1023,7 @@ public class Shard extends RaftActor {
             Preconditions.checkNotNull(id, "id should not be null");
             Preconditions.checkNotNull(peerAddresses, "peerAddresses should not be null");
             Preconditions.checkNotNull(datastoreContext, "dataStoreContext should not be null");
-            Preconditions.checkNotNull(schemaContext, "schemaContext should not be null");
+            Preconditions.checkNotNull(schemaContextProvider, "schemaContextProvider should not be null");
         }
 
         public Props props() {
@@ -938,4 +1042,8 @@ public class Shard extends RaftActor {
     Ticker ticker() {
         return Ticker.systemTicker();
     }
+
+    void scheduleNextPendingTransaction() {
+        self().tell(RESUME_NEXT_PENDING_TRANSACTION, ActorRef.noSender());
+    }
 }