*/
package org.opendaylight.controller.cluster.raft;
+import com.google.common.annotations.VisibleForTesting;
+import javax.annotation.Nonnull;
+import javax.annotation.Nullable;
+import org.opendaylight.controller.cluster.raft.behaviors.LeaderInstallSnapshotState;
+
/**
- * The state of the followers log as known by the Leader
+ * The state of the followers log as known by the Leader.
*/
public interface FollowerLogInformation {
/**
- * Increment the value of the nextIndex
- * @return
+ * Increments the value of the follower's next index.
+ *
+ * @return the new value of nextIndex.
*/
long incrNextIndex();
/**
- * Decrement the value of the nextIndex
- * @return
+ * Decrements the value of the follower's next index.
+ *
+ * @return true if the next index was decremented, ie it was previously >= 0, false otherwise.
*/
- long decrNextIndex();
+ boolean decrNextIndex();
/**
- * Sets the index of the next log entry for this follower.
+ * Sets the index of the follower's next log entry.
*
- * @param nextIndex
+ * @param nextIndex the new index.
* @return true if the new index differed from the current index and the current index was updated, false
* otherwise.
*/
boolean setNextIndex(long nextIndex);
/**
- * Increment the value of the matchIndex
- * @return
+ * Increments the value of the follower's match index.
+ *
+ * @return the new value of matchIndex.
*/
long incrMatchIndex();
/**
- * Sets the index of the highest log entry for this follower.
+ * Sets the index of the follower's highest log entry.
*
- * @param matchIndex
+ * @param matchIndex the new index.
* @return true if the new index differed from the current index and the current index was updated, false
* otherwise.
*/
boolean setMatchIndex(long matchIndex);
/**
- * The identifier of the follower
- * This could simply be the url of the remote actor
+ * Returns the identifier of the follower.
+ *
+ * @return the identifier of the follower.
*/
String getId();
/**
- * for each server, index of the next log entry
- * to send to that server (initialized to leader
- * last log index + 1)
+ * Returns the index of the next log entry to send to the follower.
+ *
+ * @return index of the follower's next log entry.
*/
long getNextIndex();
/**
- * for each server, index of highest log entry
- * known to be replicated on server
- * (initialized to 0, increases monotonically)
+ * Returns the index of highest log entry known to be replicated on the follower.
+ *
+ * @return the index of highest log entry.
*/
long getMatchIndex();
/**
- * Checks if the follower is active by comparing the last updated with the duration
- * @return boolean
+ * Checks if the follower is active by comparing the time of the last activity with the election time out. The
+ * follower is active if some activity has occurred for the follower within the election time out interval.
+ *
+ * @return true if follower is active, false otherwise.
*/
boolean isFollowerActive();
/**
- * restarts the timeout clock of the follower
+ * Marks the follower as active. This should be called when some activity has occurred for the follower.
*/
void markFollowerActive();
/**
- * This will stop the timeout clock
+ * Marks the follower as inactive. This should only be called from unit tests.
*/
+ @VisibleForTesting
void markFollowerInActive();
/**
- * This will return the active time of follower, since it was last reset
- * @return time in milliseconds
+ * Returns the time since the last activity occurred for the follower.
+ *
+ * @return time in milliseconds since the last activity from the follower.
*/
long timeSinceLastActivity();
+ /**
+ * This method checks if the next replicate message can be sent to the follower. This is an optimization to avoid
+ * sending duplicate message too frequently if the last replicate message was sent and no reply has been received
+ * yet within the current heart beat interval
+ *
+ * @return true if it is ok to replicate, false otherwise
+ */
+ boolean okToReplicate();
+
+ /**
+ * Returns the log entry payload data version of the follower.
+ *
+ * @return the payload data version.
+ */
+ short getPayloadVersion();
+
+ /**
+ * Sets the payload data version of the follower.
+ *
+ * @param payloadVersion the payload data version.
+ */
+ void setPayloadVersion(short payloadVersion);
+
+ /**
+ * Returns the the raft version of the follower.
+ *
+ * @return the raft version of the follower.
+ */
+ short getRaftVersion();
+
+ /**
+ * Sets the raft version of the follower.
+ *
+ * @param raftVersion the raft version.
+ */
+ void setRaftVersion(short raftVersion);
+
+ /**
+ * Returns the LeaderInstallSnapshotState for the in progress install snapshot.
+ *
+ * @return the LeaderInstallSnapshotState if a snapshot install is in progress, null otherwise.
+ */
+ @Nullable
+ LeaderInstallSnapshotState getInstallSnapshotState();
+
+ /**
+ * Sets the LeaderInstallSnapshotState when an install snapshot is initiated.
+ *
+ * @param state the LeaderInstallSnapshotState
+ */
+ void setLeaderInstallSnapshotState(@Nonnull LeaderInstallSnapshotState state);
+
+ /**
+ * Clears the LeaderInstallSnapshotState when an install snapshot is complete.
+ */
+ void clearLeaderInstallSnapshotState();
}
Code Review / controller.git / blobdiff