org.apache.slider.server.servicemonitor

Class ProbeWorker

java.lang.Object

org.apache.slider.server.servicemonitor.ProbeWorker

All Implemented Interfaces:

Runnable

public class ProbeWorker
extends Object
implements Runnable

This is the entry point to do work. A list of probes is taken in, in order of booting. Once live they go to the live probes list. The dependency probes are a set of probes for dependent services, all of which must be live before boot probes commence. The boot probes are executed and are allowed to fail; failure is interpreted as "not yet live" Once all boot probes are live, the live list is used for probes; these must not fail. There is no timeout on dependency probe bootstrap time, because of the notion that restarting this service will have no effect on the dependencies.

Field Summary

Fields

Modifier and Type	Field and Description
protected Probe	currentProbe
static String	FAILED_TO_BOOT
static String	FAILURE_OF_A_LIVE_PROBE_DURING_BOOTSTRAPPING
int	interval
protected ProbeStatus	lastFailingBootstrapProbe
protected ProbeStatus	lastStatus
protected static org.slf4j.Logger	log

Constructor Summary

Constructors

Constructor and Description
ProbeWorker(List<Probe> monitorProbes, List<Probe> dependencyProbes, int interval, int bootstrapTimeout) Create a probe worker

Method Summary

Methods

Modifier and Type	Method and Description
boolean	checkAndReportBootstrapProbes() run through all the bootstrap probes and see if they are live.
boolean	checkAndReportDependencyProbes() Run through all the dependency probes and report their outcomes successes (even if they fail)
protected void	checkAndReportLiveProbes() run through all the live probes, pinging and reporting them.
protected void	executeProbePhases() Run the set of probes relevant for this phase of the probe lifecycle.
int	getBootstrapTimeout()
Probe	getCurrentProbe()
ProbeStatus	getLastStatus()
ProbePhase	getProbePhase()
void	init()
boolean	isBootstrapTimeExceeded() predicate that gets current time and checks for its time being exceeded.
protected void	probeFailed(ProbeFailedException e)
void	run()
void	setMustExit()
void	setReportHandler(ProbeReportHandler reportHandler)
void	verifyBootstrapHasNotTimedOut() This checks that bootstrap operations have not timed out

Methods inherited from class java.lang.Object

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

Field Detail

log

protected static final org.slf4j.Logger log

FAILED_TO_BOOT

public static final String FAILED_TO_BOOT

See Also:

Constant Field Values

FAILURE_OF_A_LIVE_PROBE_DURING_BOOTSTRAPPING

public static final String FAILURE_OF_A_LIVE_PROBE_DURING_BOOTSTRAPPING

See Also:

Constant Field Values

interval

public final int interval

lastStatus

protected volatile ProbeStatus lastStatus

lastFailingBootstrapProbe

protected volatile ProbeStatus lastFailingBootstrapProbe

currentProbe

protected volatile Probe currentProbe

Constructor Detail

ProbeWorker

public ProbeWorker(List<Probe> monitorProbes,
           List<Probe> dependencyProbes,
           int interval,
           int bootstrapTimeout)

Create a probe worker

Parameters:

monitorProbes - list of probes that must boot and then go live -after which they must stay live.

dependencyProbes - the list of dependency probes that must all succeed before any attempt to probe the direct probe list is performed. Once the dependency phase has completed, these probes are never checked again.

interval - probe interval in milliseconds.

bootstrapTimeout - timeout for bootstrap in milliseconds

Method Detail

init

public void init()
          throws IOException

Throws:

IOException

setReportHandler

public void setReportHandler(ProbeReportHandler reportHandler)

setMustExit

public void setMustExit()

getLastStatus

public ProbeStatus getLastStatus()

getCurrentProbe

public Probe getCurrentProbe()

getProbePhase

public ProbePhase getProbePhase()

checkAndReportDependencyProbes

public boolean checkAndReportDependencyProbes()
                                       throws ProbeInterruptedException

Run through all the dependency probes and report their outcomes successes (even if they fail)

Returns:

true iff all the probes have succeeded.

Throws:

ProbeInterruptedException - if the process was interrupted.

getBootstrapTimeout

public int getBootstrapTimeout()

verifyBootstrapHasNotTimedOut

public void verifyBootstrapHasNotTimedOut()
                                   throws ProbeFailedException

This checks that bootstrap operations have not timed out

Throws:

ProbeFailedException - if the bootstrap has failed

isBootstrapTimeExceeded

public boolean isBootstrapTimeExceeded()

predicate that gets current time and checks for its time being exceeded.

Returns:

true iff the current time is > the end time

checkAndReportBootstrapProbes

public boolean checkAndReportBootstrapProbes()
                                      throws ProbeInterruptedException,
                                             ProbeFailedException

run through all the bootstrap probes and see if they are live.

Returns:

true iff all boot probes succeeded

Throws:

ProbeInterruptedException - the probe interruption flags

ProbeFailedException - if a probe failed.

checkAndReportLiveProbes

protected void checkAndReportLiveProbes()
                                 throws ProbeFailedException,
                                        ProbeInterruptedException

run through all the live probes, pinging and reporting them. A single probe failure is turned into an exception

Throws:

ProbeFailedException - a probe failed

ProbeInterruptedException - the probe process was explicitly interrupted

executeProbePhases

protected void executeProbePhases()
                           throws ProbeFailedException,
                                  ProbeInterruptedException

Run the set of probes relevant for this phase of the probe lifecycle.

Throws:

ProbeFailedException - a probe failed

ProbeInterruptedException - the probe process was explicitly interrupted

run

public void run()

Specified by:

run in interface Runnable

probeFailed

protected void probeFailed(ProbeFailedException e)