BUG-5280: add frontend state lifecycle

[controller.git] / opendaylight / md-sal / sal-distributed-datastore / src / main / java / org / opendaylight / controller / cluster / datastore / Shard.java

diff --git a/opendaylight/md-sal/sal-distributed-datastore/src/main/java/org/opendaylight/controller/cluster/datastore/Shard.java b/opendaylight/md-sal/sal-distributed-datastore/src/main/java/org/opendaylight/controller/cluster/datastore/Shard.java
index 7ca79fc2349add0e9c19236a945aaed53676b45d..7915a6286ed8746149f62dc349bfb4d79a3ce29d 100644 (file)
--- a/opendaylight/md-sal/sal-distributed-datastore/src/main/java/org/opendaylight/controller/cluster/datastore/Shard.java
+++ b/opendaylight/md-sal/sal-distributed-datastore/src/main/java/org/opendaylight/controller/cluster/datastore/Shard.java
@@ -18,13 +18,14 @@ 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;
@@ -164,8 +165,8 @@ 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();
 
     protected Shard(final AbstractBuilder<?, ?> builder) {
         super(builder.getId().toString(), builder.getPeerAddresses(),
@@ -174,6 +175,7 @@ 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());
 
@@ -733,7 +735,7 @@ public class Shard extends RaftActor {
                     persistenceId(), getId());
             }
 
-            store.closeAllTransactionChains();
+            store.purgeLeaderState();
         }
 
         if (hasLeader && !isIsolatedLeader()) {
@@ -745,8 +747,18 @@ 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();
@@ -765,9 +777,13 @@ 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();
         }
     }