org.lsst.ccs.services.alert

Class AlertService

java.lang.Object

org.lsst.ccs.services.alert.AlertService

All Implemented Interfaces:

HasLifecycle, ServiceLifecycle, AgentService

public final class AlertService
extends Object
implements HasLifecycle, AgentService, ServiceLifecycle

Agent AlertService. It is a Service that is created for all Agents. It offers an interface to manage alerts: raise and clear alerts. Any time alerts are either raised or cleared registered s will be notified via an AlertEvent with the information needed to act upon the change. This Alert management component is activated for all agents. The AlertService also keeps a summary and a history for all the raised alerts that have not been cleared. For Agents of type WORKER or for services (MCM, OCS_BRIDGE, etc) the internal raised alert summary is published on the status bus wrapped in a StatusRaisedAlertSummary object when: - the Agent starts up - when a Console or a Service connects to the buses For all Agents this raised alert summary can be published on request via the #publishRaisedAlertSummary method; this method is meant to be invoked by Agents that do not hold an up-to-date copy of an alert summary object. Raised Alert listening on the buses: the AlertService also provides the ability to start a status bus message listener to intercept Alert related status messages from other subsystems and notify the registered AlertListeners accordingly. To activate the status bus message listener the method #startStatusAlertListening must be invoked before theHasLifecycle#start phase, providing a Predicate<AgentInfo> to select which agents to listen to. By default status bus listening is activated for Consoles and Services with a Predicate selecting either WORKERS or Services.

Author:

LSST CCS Team

Constructor Summary

Constructors

Constructor and Description
AlertService()

Method Summary

Modifier and Type	Method and Description
void	addListener(AlertListener listener)
void	build() First lifecycle hook.
String[]	clearAlerts(String... alertId) Method similar to #clearAlerts(String, String...) with default source equal to the agent name.
String[]	clearAlertsForSource(String source, String... alertId) Clear one or more Alerts for a given source by providing the alert id of the alerts to be cleared.
String[]	clearAllAlerts() Method similar to #clearAllAlerts(String) with default source equal to the agent name.
String[]	clearAllAlertsForSource(String source) Attempt to clear all the outstanding alerts for a given source.
String	getAgentServiceName() Get the name of this service.
Map<String,RaisedAlertSummary>	getAllSummaries()
RaisedAlertSummary	getRaisedAlertSummary() Get the Subsystem's RaisedAlertSummary.
RaisedAlertSummary	getSummary(String source)
void	postInit() Population of clear alert handlers.
void	postShutdown() Called from the enclosing Subsystem when org.lsst.ccs.Subsystem#shutdown() has been called after shtudownNow has been invoked on all the children.
String	printRegisteredAlerts() Print the list of Alerts that have been registered for this Agent.
void	publishRaisedAlertSummary() Publish on the status bus the Subsystem's RaisedAlertSummary.
void	raiseAlert(Alert alert, AlertState severity, String cause) Method similar to #raiseAlert(String,Alert,AlertState,String) where the source argument is set to be the agent name.
void	raiseAlert(String source, Alert alert, AlertState severity, String cause) Raise an Alert with a given AlertState for a given source.
void	registerAlert(Alert alert) Register an Alert without a ClearAlertHandler.
void	registerAlert(Alert alert, ClearAlertHandler clearAlertHandler) Register an Alert and the corresponding ClearAlertHandler to be invoked when clearing the Alert.
void	removeListener(AlertListener listener)
void	requiresPublicationOfAlertHistory()
void	setAccumulationDuration(Duration accDur)
void	shutdown() Called from the enclosing Subsystem when org.lsst.ccs.Subsystem#shutdown() has been called.
void	start() Called from the enclosing Subsystem when Agent.startAgent() has been called and after HardwareController components have been handled.
void	startStatusAlertListening(Predicate<AgentInfo> agentSelection)

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Methods inherited from interface org.lsst.ccs.framework.HasLifecycle

init, postBuild, postStart

Methods inherited from interface org.lsst.ccs.services.AgentService

startForAgent

Methods inherited from interface org.lsst.ccs.ServiceLifecycle

afterInit, afterStart, preBuild, preInit, preShutdown, preStart

Constructor Detail

AlertService

public AlertService()

Method Detail

getAgentServiceName

public String getAgentServiceName()

Description copied from interface: AgentService

Get the name of this service. This name will be used to add the given service to the lookup tree.

Specified by:

getAgentServiceName in interface AgentService

Returns:

the AgentService name.

build

public void build()

Description copied from interface: HasLifecycle

First lifecycle hook. Modification of the component tree is allowed at this stage. After this stage the tree of component cannot be modified anymore. This is where agent periodic tasks should be scheduled.

Specified by:

build in interface HasLifecycle

postInit

public void postInit()

Population of clear alert handlers. We are also starting listening on the status bus when this agent is either a Graphical Console or a Service. We are listening for Alert related status messages as published by workers or services.

Specified by:

postInit in interface HasLifecycle

start

public void start()

Description copied from interface: HasLifecycle

Called from the enclosing Subsystem when Agent.startAgent() has been called and after HardwareController components have been handled. At the time it is called :

• the PhaseState is INITIALIZING
• connection with the messaging layer is effective, the enclosing subsystem has started StatusHeartBeat publication
• the startup configuration has been loaded (if provided). IMPORTANT NOTE : This statement will not be true in future releases. Code that expect the startup configuration to be loaded should be moved from start to postStart.

It is unnecessary to call super.start()

Specified by:

start in interface HasLifecycle

shutdown

public void shutdown()

Description copied from interface: HasLifecycle

Called from the enclosing Subsystem when org.lsst.ccs.Subsystem#shutdown() has been called. At the time it is called :

• PhaseState is CLOSING.
• HardwareController.checkStopped() has been called

It should be overridden to free non hardware related resources.

Specified by:

shutdown in interface HasLifecycle

postShutdown

public void postShutdown()

Description copied from interface: HasLifecycle

Called from the enclosing Subsystem when org.lsst.ccs.Subsystem#shutdown() has been called after shtudownNow has been invoked on all the children. At the time it is called :

• PhaseState is CLOSING.
• HardwareController.checkStopped() has been called

It should be overridden to free non hardware related resources.

Specified by:

postShutdown in interface HasLifecycle

registerAlert

public void registerAlert(Alert alert,
                          ClearAlertHandler clearAlertHandler)

Register an Alert and the corresponding ClearAlertHandler to be invoked when clearing the Alert. If the provided ClearAlertHandler is null, the default implementation will be used.

Parameters:

alert - The Alert being registered.

clearAlertHandler - The ClearAlertHandler used when clearing the Alert. If null, the default implementation will be used.

registerAlert

public void registerAlert(Alert alert)

Register an Alert without a ClearAlertHandler. The default ClearAlertHandler will be used when clearing the registered Alert.

Parameters:

alert - The Alert being registered.

startStatusAlertListening

public void startStatusAlertListening(Predicate<AgentInfo> agentSelection)

requiresPublicationOfAlertHistory

public void requiresPublicationOfAlertHistory()

raiseAlert

public void raiseAlert(String source,
                       Alert alert,
                       AlertState severity,
                       String cause)

Raise an Alert with a given AlertState for a given source. This raises an internal alert and all the registered AlertListeners will be notified with an AlertEvent of type ALERT_RAISED. A special case is when the source is equal to the agent name. In this case we have a listener that will publish a status message on the buses.

Parameters:

alert - The Alert instance to be raised

severity - The AlertState of this Alert.

cause - The reason the Alert was raised.

source - The source for which we raise an alert

raiseAlert

public void raiseAlert(Alert alert,
                       AlertState severity,
                       String cause)

Method similar to #raiseAlert(String,Alert,AlertState,String) where the source argument is set to be the agent name. This is a convenience method that will trigger a status message publication.

Parameters:

alert -

severity -

cause -

clearAlertsForSource

public String[] clearAlertsForSource(String source,
                                     String... alertId)

Clear one or more Alerts for a given source by providing the alert id of the alerts to be cleared.

Parameters:

source - The source for which to clear the alerts.

alertId - the Id of the Alerts to be cleared.

Returns:

The String array with the ids of the alerts that have been cleared.

clearAlerts

@Command(description="Clear alerts",
         type=ACTION,
         category=CORE)
public String[] clearAlerts(String... alertId)

Method similar to #clearAlerts(String, String...) with default source equal to the agent name. This method is annotated to be invoked over the buses by other consoles.

Parameters:

alertId -

Returns:

clearAllAlertsForSource

public String[] clearAllAlertsForSource(String source)

Attempt to clear all the outstanding alerts for a given source.

Parameters:

source - the source for which to clear the alerts.

Returns:

The String array with the ids of the alerts that have been cleared.

clearAllAlerts

@Command(description="Clear all alerts",
         type=ACTION,
         category=CORE)
public String[] clearAllAlerts()

Method similar to #clearAllAlerts(String) with default source equal to the agent name. This method is annotated to be invoked over the buses by other consoles.

Returns:

getRaisedAlertSummary

@Command(description="Get the Raised Alert Summary",
         type=QUERY)
public RaisedAlertSummary getRaisedAlertSummary()

Get the Subsystem's RaisedAlertSummary.

Returns:

The RaisedAlertSummary for this subsystem.

publishRaisedAlertSummary

@Command(description="Publish the Raised Alert Summary",
         type=QUERY,
         category=SYSTEM)
public void publishRaisedAlertSummary()

Publish on the status bus the Subsystem's RaisedAlertSummary.

printRegisteredAlerts

@Command(description="Print Registered Alerts",
         type=QUERY,
         category=USER)
public String printRegisteredAlerts()

Print the list of Alerts that have been registered for this Agent.

Returns:

a String containing the list of registered alerts.

addListener

public final void addListener(AlertListener listener)

removeListener

public final void removeListener(AlertListener listener)

getSummary

public RaisedAlertSummary getSummary(String source)

getAllSummaries

public Map<String,RaisedAlertSummary> getAllSummaries()

setAccumulationDuration

public void setAccumulationDuration(Duration accDur)