NewAgent creates a new Agent that receives membership changes from the discovery service.

EventTypeAdd indicates that a node has been added.

EventTypeDel indicates that a node has been removed.

NodeTypeExecutor indicates that the node is an executor.

NodeTypeMaster indicates that the node is a master.

Event is a node membership change event.

Node describes the information of a node.

Agent registers receives membership changes of all nodes.

EventType describes the type of the event, i.e.

NodeType describes the type of the node.

Snapshot is the current service membership snapshot.