Bug 7521: Convert Snapshot to store a State instance

[controller.git] / opendaylight / md-sal / sal-akka-raft / src / main / java / org / opendaylight / controller / cluster / raft / RaftActorSnapshotCohort.java

diff --git a/opendaylight/md-sal/sal-akka-raft/src/main/java/org/opendaylight/controller/cluster/raft/RaftActorSnapshotCohort.java b/opendaylight/md-sal/sal-akka-raft/src/main/java/org/opendaylight/controller/cluster/raft/RaftActorSnapshotCohort.java
index ad68726371621cf210f0ba1407955ca84672e9c7..a02b295dbc1ed7b39180d880c9b5eade21f78b54 100644 (file)
--- a/opendaylight/md-sal/sal-akka-raft/src/main/java/org/opendaylight/controller/cluster/raft/RaftActorSnapshotCohort.java
+++ b/opendaylight/md-sal/sal-akka-raft/src/main/java/org/opendaylight/controller/cluster/raft/RaftActorSnapshotCohort.java
@@ -8,6 +8,12 @@
 package org.opendaylight.controller.cluster.raft;
 
 import akka.actor.ActorRef;
+import com.google.common.io.ByteSource;
+import java.io.IOException;
+import java.io.OutputStream;
+import java.util.Optional;
+import javax.annotation.Nonnull;
+import org.opendaylight.controller.cluster.raft.persisted.Snapshot;
 
 /**
  * Interface for a class that participates in raft actor snapshotting.
@@ -21,13 +27,31 @@ public interface RaftActorSnapshotCohort {
      * created. The implementation should send a CaptureSnapshotReply to the given actor.
      *
      * @param actorRef the actor to which to respond
+     * @param installSnapshotStream Optional OutputStream that is present if the snapshot is to also be installed
+     *        on a follower. The implementation must serialize its state to the OutputStream and return the
+     *        installSnapshotStream instance in the CaptureSnapshotReply along with the snapshot State instance.
+     *        The snapshot State is serialized directly to the snapshot store while the OutputStream is used to send
+     *        the state data to follower(s) in chunks. The {@link #deserializeSnapshot} method is used to convert the
+     *        serialized data back to a State instance on the follower end. The serialization for snapshot install is
+     *        passed off so the cost of serialization is not charged to the raft actor's thread.
      */
-    void createSnapshot(ActorRef actorRef);
+    void createSnapshot(@Nonnull ActorRef actorRef, @Nonnull Optional<OutputStream> installSnapshotStream);
 
     /**
      * This method is called to apply a snapshot installed by the leader.
      *
-     * @param snapshotBytes a snapshot of the state of the actor
+     * @param snapshotState a snapshot of the state of the actor
      */
-    void applySnapshot(byte[] snapshotBytes);
+    void applySnapshot(@Nonnull Snapshot.State snapshotState);
+
+    /**
+     * This method is called to de-serialize snapshot data that was previously serialized via {@link #createSnapshot}
+     * to a State instance.
+     *
+     * @param snapshotBytes the ByteSource containing the serialized data
+     * @return the converted snapshot State
+     * @throws IOException if an error occurs accessing the ByteSource or de-serializing
+     */
+    @Nonnull
+    Snapshot.State deserializeSnapshot(@Nonnull ByteSource snapshotBytes) throws IOException;
 }