org.apache.flink.runtime.leaderelection

Interface LeaderElection

All Superinterfaces:

AutoCloseable

All Known Implementing Classes:

StandaloneLeaderElection

public interface LeaderElection
extends AutoCloseable

LeaderElection serves as a proxy between LeaderElectionService and LeaderContender.

Method Summary

Modifier and Type	Method and Description
void	close() Closes the LeaderElection by deregistering the LeaderContender from the underlying leader election.
CompletableFuture<Void>	confirmLeadershipAsync(UUID leaderSessionID, String leaderAddress) Confirms that the LeaderContender has accepted the leadership identified by the given leader session id.
CompletableFuture<Boolean>	hasLeadershipAsync(UUID leaderSessionId) Returns true if the service's LeaderContender has the leadership under the given leader session ID acquired.
void	startLeaderElection(LeaderContender contender) Registers the passed LeaderContender with the leader election process.

Method Detail

startLeaderElection

void startLeaderElection(LeaderContender contender)
                  throws Exception

Registers the passed LeaderContender with the leader election process.

Throws:

Exception

confirmLeadershipAsync

CompletableFuture<Void> confirmLeadershipAsync(UUID leaderSessionID,
                                               String leaderAddress)

Confirms that the LeaderContender has accepted the leadership identified by the given leader session id. It also publishes the leader address under which the leader is reachable.

The data is only confirmed if the leadership is still acquired.

The intention of this method is to establish an order between setting the new leader session ID in the LeaderContender and publishing the new leader session ID and the related leader address to the leader retrieval services.

Parameters:

leaderSessionID - The new leader session ID

leaderAddress - The address of the new leader

hasLeadershipAsync

CompletableFuture<Boolean> hasLeadershipAsync(UUID leaderSessionId)

Returns true if the service's LeaderContender has the leadership under the given leader session ID acquired.

Parameters:

leaderSessionId - identifying the current leader

Returns:

true if the associated LeaderContender is the leader, otherwise false

close

void close()
    throws Exception

Closes the LeaderElection by deregistering the LeaderContender from the underlying leader election. LeaderContender.revokeLeadership() will be called if the service still holds the leadership.

Specified by:

close in interface AutoCloseable

Throws:

Exception