org.apache.nifi.cluster.manager

Interface ClusterManager

All Superinterfaces:

NodeInformant

All Known Subinterfaces:

HttpClusterManager

All Known Implementing Classes:

WebClusterManager

public interface ClusterManager
extends NodeInformant

Defines the interface for a ClusterManager. The cluster manager is a threadsafe centralized manager for a cluster. Members of a cluster are nodes. A member becomes a node by issuing a connection request to the manager. The manager maintains the set of nodes. Nodes may be disconnected, reconnected, and deleted. Nodes are responsible for sending heartbeats to the manager to indicate their liveliness. A manager may disconnect a node if it does not receive a heartbeat within a configurable time period. A cluster manager instance may be configured with how often to monitor received heartbeats (getHeartbeatMonitoringIntervalSeconds()) and the maximum time that may elapse between node heartbeats before disconnecting the node (getMaxHeartbeatGapSeconds()). Since only a single node may execute isolated processors, the cluster manager maintains the notion of a primary node. The primary node is chosen at cluster startup and retains the role until a user requests a different node to be the primary node.

Method Summary

Methods

Modifier and Type	Method and Description
void	deleteNode(String nodeId, String userDn) Deletes the node with the given node identifier.
BulletinRepository	getBulletinRepository()
int	getHeartbeatMonitoringIntervalSeconds()
int	getMaxHeartbeatGapSeconds()
Node	getNode(String nodeId)
List<Event>	getNodeEvents(String nodeId) Returns a list of node events for the node with the given identifier.
Set<NodeIdentifier>	getNodeIds(Node.Status... statuses)
Set<Node>	getNodes(Node.Status... statuses)
Node	getPrimaryNode()
ProcessGroupStatus	getProcessGroupStatus(String groupId)
SystemDiagnostics	getSystemDiagnostics()
void	handleHeartbeat(Heartbeat heartbeat) Handles a node's heartbeat.
ConnectionResponse	requestConnection(ConnectionRequest request) Requests a connection to the cluster.
void	requestDisconnection(String nodeId, String userDn) Requests the node with the given identifier be disconnected.
void	requestReconnection(String nodeId, String userDn) Services reconnection requests for a given node.
void	setPrimaryNode(String nodeId, String userDn) Revokes the primary role from the current primary node and assigns the primary role to given given node ID.

Methods inherited from interface org.apache.nifi.remote.cluster.NodeInformant

getNodeInformation

Method Detail

handleHeartbeat

void handleHeartbeat(Heartbeat heartbeat)

Handles a node's heartbeat.

Parameters:

heartbeat - a heartbeat

getNodes

Set<Node> getNodes(Node.Status... statuses)

Parameters:

statuses - the statuses of the nodes

Returns:

the set of nodes

getNode

Node getNode(String nodeId)

Parameters:

nodeId - node identifier

Returns:

returns the node with the given identifier or null if node does not exist

getNodeIds

Set<NodeIdentifier> getNodeIds(Node.Status... statuses)

Parameters:

statuses - statuses

Returns:

the set of node identifiers with the given node status

deleteNode

void deleteNode(String nodeId,
              String userDn)
                throws UnknownNodeException,
                       IllegalNodeDeletionException

Deletes the node with the given node identifier. If the given node is the primary node, then a subsequent request may be made to the manager to set a new primary node.

Parameters:

nodeId - the node identifier

userDn - the Distinguished Name of the user requesting the node be deleted from the cluster

Throws:

UnknownNodeException - if the node does not exist

IllegalNodeDeletionException - if the node is not in a disconnected state

requestConnection

ConnectionResponse requestConnection(ConnectionRequest request)

Requests a connection to the cluster.

Parameters:

request - the request

Returns:

the response

requestReconnection

void requestReconnection(String nodeId,
                       String userDn)
                         throws UnknownNodeException,
                                IllegalNodeReconnectionException

Services reconnection requests for a given node. If the node indicates reconnection failure, then the node will be set to disconnected. Otherwise, a reconnection request will be sent to the node, initiating the connection handshake.

Parameters:

nodeId - a node identifier

userDn - the Distinguished Name of the user requesting the reconnection

Throws:

UnknownNodeException - if the node does not exist

IllegalNodeReconnectionException - if the node is not disconnected

requestDisconnection

void requestDisconnection(String nodeId,
                        String userDn)
                          throws UnknownNodeException,
                                 IllegalNodeDisconnectionException,
                                 NodeDisconnectionException

Requests the node with the given identifier be disconnected.

Parameters:

nodeId - the node identifier

userDn - the Distinguished Name of the user requesting the disconnection

Throws:

UnknownNodeException - if the node does not exist

IllegalNodeDisconnectionException - if the node cannot be disconnected due to the cluster's state (e.g., node is last connected node or node is primary)

UnknownNodeException - if the node does not exist

IllegalNodeDisconnectionException - if the node is not disconnected

NodeDisconnectionException - if the disconnection failed

getHeartbeatMonitoringIntervalSeconds

int getHeartbeatMonitoringIntervalSeconds()

Returns:

the time in seconds to wait between successive executions of heartbeat monitoring

getMaxHeartbeatGapSeconds

int getMaxHeartbeatGapSeconds()

Returns:

the maximum time in seconds that is allowed between successive heartbeats of a node before disconnecting the node

getNodeEvents

List<Event> getNodeEvents(String nodeId)

Returns a list of node events for the node with the given identifier. The events will be returned in order of most recent to least recent according to the creation date of the event.

Parameters:

nodeId - the node identifier

Returns:

the list of events or an empty list if no node exists with the given identifier

setPrimaryNode

void setPrimaryNode(String nodeId,
                  String userDn)
                    throws UnknownNodeException,
                           IneligiblePrimaryNodeException,
                           PrimaryRoleAssignmentException

Revokes the primary role from the current primary node and assigns the primary role to given given node ID. If role revocation fails, then the current primary node is set to disconnected while retaining the primary role and no role assignment is performed. If role assignment fails, then the given node is set to disconnected and is given the primary role.

Parameters:

nodeId - the node identifier

userDn - the Distinguished Name of the user requesting that the Primary Node be assigned

Throws:

UnknownNodeException - if the node with the given identifier does not exist

IneligiblePrimaryNodeException - if the node with the given identifier is not eligible to be the primary node

PrimaryRoleAssignmentException - if the cluster was unable to change the primary role to the requested node

getPrimaryNode

Node getPrimaryNode()

Returns:

the primary node of the cluster or null if no primary node exists

getBulletinRepository

BulletinRepository getBulletinRepository()

Returns:

the bulletin repository

getProcessGroupStatus

ProcessGroupStatus getProcessGroupStatus(String groupId)

Parameters:

groupId - groupId

Returns:

a ProcessGroupStatus that represents the status of all nodes with the given Node.Statuses for the given ProcessGroup id, or null if no nodes exist with the given statuses

getSystemDiagnostics

SystemDiagnostics getSystemDiagnostics()

Returns:

a merged representation of the System Diagnostics for all nodes in the cluster