org.apache.nifi.cluster.coordination

Interface ClusterCoordinator

public interface ClusterCoordinator

Responsible for coordinating nodes in the cluster

Method Summary

Modifier and Type	Method and Description
void	addRole(String clusterRole) Notifies the cluster coordinator that this node has been granted the given role
void	disconnectionRequestedByNode(NodeIdentifier nodeId, DisconnectionCode disconnectionCode, String explanation) Notifies the Cluster Coordinator that the node with the given ID has requested to disconnect from the cluster.
void	finishNodeConnection(NodeIdentifier nodeId) Indicates that the node has sent a valid heartbeat and should now be considered part of the cluster
Map<NodeConnectionState,List<NodeIdentifier>>	getConnectionStates() Returns a Map of NodeConnectionStatus to all Node Identifiers that have that status.
NodeConnectionStatus	getConnectionStatus(NodeIdentifier nodeId) Returns the current status of the node with the given identifier
NodeIdentifier	getElectedActiveCoordinatorNode()
NodeIdentifier	getLocalNodeIdentifier()
List<NodeEvent>	getNodeEvents(NodeIdentifier nodeId) Returns all of the events that have occurred for the given node
NodeIdentifier	getNodeIdentifier(String uuid) Returns the NodeIdentifier that exists that has the given UUID, or null if no NodeIdentifier exists for the given UUID
Set<NodeIdentifier>	getNodeIdentifiers(NodeConnectionState... states) Returns the identifiers of all nodes that have the given connection state
NodeIdentifier	getPrimaryNode()
boolean	isActiveClusterCoordinator()
boolean	isBlockedByFirewall(String hostname) Checks if the given hostname is blocked by the configured firewall, returning true if the node is blocked, false if the node is allowed through the firewall or if there is no firewall configured
boolean	isConnected() Indicates whether or not the node is currently connected to the cluster
void	removeNode(NodeIdentifier nodeId, String userDn) Removes the given disconnected node from the cluster
void	removeRole(String clusterRole) Notifies the cluster coordinator that this node is no longer responsible for the given role
void	reportEvent(NodeIdentifier nodeId, Severity severity, String event) Reports that some event occurred that is relevant to the cluster
void	requestNodeConnect(NodeIdentifier nodeId, String userDn) Sends a request to the node to connect to the cluster.
void	requestNodeDisconnect(NodeIdentifier nodeId, DisconnectionCode disconnectionCode, String explanation) Sends a request to the node to disconnect from the cluster.
void	resetNodeStatuses(Map<NodeIdentifier,NodeConnectionStatus> statusMap) Clears the current state of all nodes and replaces them with the values provided in the given map
void	setConnected(boolean connected) Notifies the Cluster Coordinator whether or not the node is connected to the cluster
void	setFlowService(FlowService flowService) Updates the Flow Service to use for obtaining the current flow
void	setLocalNodeIdentifier(NodeIdentifier nodeId) Notifies the Cluster Coordinator of the Node Identifier that the coordinator is currently running on
void	shutdown() Notifies the Cluster Coordinator that the NiFi instance is being shutdown so that the coordinator is able to perform cleanup of resources
void	updateNodeRoles(NodeIdentifier nodeId, Set<String> roles) Updates the roles held by the given node

Method Detail

requestNodeConnect

void requestNodeConnect(NodeIdentifier nodeId,
                        String userDn)

Sends a request to the node to connect to the cluster. This will immediately set the NodeConnectionStatus to CONNECTING.

Parameters:

nodeId - the identifier of the node

userDn - the DN of the user that requested that the node connect, or null if the action is not user-driven

shutdown

void shutdown()

Notifies the Cluster Coordinator that the NiFi instance is being shutdown so that the coordinator is able to perform cleanup of resources

finishNodeConnection

void finishNodeConnection(NodeIdentifier nodeId)

Indicates that the node has sent a valid heartbeat and should now be considered part of the cluster

Parameters:

nodeId - the identifier of the node

requestNodeDisconnect

void requestNodeDisconnect(NodeIdentifier nodeId,
                           DisconnectionCode disconnectionCode,
                           String explanation)

Sends a request to the node to disconnect from the cluster. The node will be marked as disconnected immediately.

Parameters:

nodeId - the identifier of the node

disconnectionCode - the code that represents why this node is being asked to disconnect

explanation - an explanation as to why the node is being asked to disconnect from the cluster

disconnectionRequestedByNode

void disconnectionRequestedByNode(NodeIdentifier nodeId,
                                  DisconnectionCode disconnectionCode,
                                  String explanation)

Notifies the Cluster Coordinator that the node with the given ID has requested to disconnect from the cluster. If no node exists in the cluster with the given ID, this method has no effect.

Parameters:

nodeId - the identifier of the node

disconnectionCode - the code that represents why this node is requesting to disconnect

explanation - an explanation as to why the node is requesting to disconnect from the cluster

removeNode

void removeNode(NodeIdentifier nodeId,
                String userDn)

Removes the given disconnected node from the cluster

Parameters:

nodeId - the node to remove

userDn - the DN of the user requesting that the node be removed

getConnectionStatus

NodeConnectionStatus getConnectionStatus(NodeIdentifier nodeId)

Returns the current status of the node with the given identifier

Parameters:

nodeId - the identifier of the node

Returns:

the current status of the node with the given identifier, or null if no node is known with the given identifier

getNodeIdentifiers

Set<NodeIdentifier> getNodeIdentifiers(NodeConnectionState... states)

Returns the identifiers of all nodes that have the given connection state

Parameters:

states - the states of interest

Returns:

the identifiers of all nodes that have the given connection state

getConnectionStates

Map<NodeConnectionState,List<NodeIdentifier>> getConnectionStates()

Returns a Map of NodeConnectionStatus to all Node Identifiers that have that status.

Returns:

the NodeConnectionStatus for each Node in the cluster, grouped by the Connection Status

isBlockedByFirewall

boolean isBlockedByFirewall(String hostname)

Checks if the given hostname is blocked by the configured firewall, returning true if the node is blocked, false if the node is allowed through the firewall or if there is no firewall configured

Parameters:

hostname - the hostname of the node that is attempting to connect to the cluster

Returns:

true if the node is blocked, false if the node is allowed through the firewall or if there is no firewall configured

reportEvent

void reportEvent(NodeIdentifier nodeId,
                 Severity severity,
                 String event)

Reports that some event occurred that is relevant to the cluster

Parameters:

nodeId - the identifier of the node that the event pertains to, or null if not applicable

severity - the severity of the event

event - an explanation of the event

updateNodeRoles

void updateNodeRoles(NodeIdentifier nodeId,
                     Set<String> roles)

Updates the roles held by the given node

Parameters:

nodeId - the id of the node to update

roles - the new roles that the node possesses

getNodeIdentifier

NodeIdentifier getNodeIdentifier(String uuid)

Returns the NodeIdentifier that exists that has the given UUID, or null if no NodeIdentifier exists for the given UUID

Parameters:

uuid - the UUID of the NodeIdentifier to obtain

Returns:

the NodeIdentifier that exists that has the given UUID, or null if no NodeIdentifier exists for the given UUID

getNodeEvents

List<NodeEvent> getNodeEvents(NodeIdentifier nodeId)

Returns all of the events that have occurred for the given node

Parameters:

nodeId - the identifier of the node

Returns:

all of the events that have occurred for the given node

getPrimaryNode

NodeIdentifier getPrimaryNode()

Returns:

the identifier of the node that is elected primary, or null if either there is no primary or the primary is not known by this node.

getElectedActiveCoordinatorNode

NodeIdentifier getElectedActiveCoordinatorNode()

Returns:

the identifier of the node that is elected the active cluster coordinator, or null if there is no active cluster coordinator elected.

getLocalNodeIdentifier

NodeIdentifier getLocalNodeIdentifier()

Returns:

the identifier of this node, if it is known, null if the Node Identifier has not yet been established.

isActiveClusterCoordinator

boolean isActiveClusterCoordinator()

Returns:

true if this node has been elected the active cluster coordinator, false otherwise.

setFlowService

void setFlowService(FlowService flowService)

Updates the Flow Service to use for obtaining the current flow

Parameters:

flowService - the flow service to use for obtaining the current flow

resetNodeStatuses

void resetNodeStatuses(Map<NodeIdentifier,NodeConnectionStatus> statusMap)

Clears the current state of all nodes and replaces them with the values provided in the given map

Parameters:

statusMap - the new states of all nodes in the cluster

setLocalNodeIdentifier

void setLocalNodeIdentifier(NodeIdentifier nodeId)

Notifies the Cluster Coordinator of the Node Identifier that the coordinator is currently running on

Parameters:

nodeId - the ID of the current node

setConnected

void setConnected(boolean connected)

Notifies the Cluster Coordinator whether or not the node is connected to the cluster

Parameters:

connected - true if the node is connected to a cluster, false otherwise.

isConnected

boolean isConnected()

Indicates whether or not the node is currently connected to the cluster

Returns:

true if connected, false otherwise

addRole

void addRole(String clusterRole)

Notifies the cluster coordinator that this node has been granted the given role

Parameters:

clusterRole - the role that this node has been granted

removeRole

void removeRole(String clusterRole)

Notifies the cluster coordinator that this node is no longer responsible for the given role

Parameters:

clusterRole - the role that this node is no longer responsible for