org.opends.server.monitors

Class LocalBackendMonitor<B extends LocalBackend<?>>

java.lang.Object

org.opends.server.api.MonitorProvider

org.opends.server.monitors.LocalBackendMonitor<B>

Type Parameters:

B - The type of local backend associated with this monitor.

All Implemented Interfaces:

MeterBinder

Direct Known Subclasses:

PluggableBackendMonitor

public class LocalBackendMonitor<B extends LocalBackend<?>>
extends MonitorProvider

This class implements a monitor provider that will report generic information for an enabled Directory Server backend, including its backend ID, base DNs, writability mode, and the number of entries it contains.

Sub-classes may override addAdditionalMetrics() in order to add implementation specific monitoring metrics.

Field Summary

Fields inherited from class org.opends.server.api.MonitorProvider

registry

Constructor Summary

Constructors

Constructor and Description
LocalBackendMonitor(B backend) Creates a new instance of this backend monitor provider that will work with the provided backend.

Method Summary

Modifier and Type	Method and Description
protected void	addAdditionalMetrics() Adds additional metrics specific to the local backend implementation in this monitor provider's MeterRegistry.
protected void	addMonitorObjectClassNames(Attribute ocAttr) Adds to the provided attribute the objectclass names that should be included in the monitor entry created from this monitor provider.
void	bindTo(MeterRegistry parent) .
protected Dn	computeMonitorInstanceDn() Returns the monitor instance DN for this monitor provider.
void	deregisterBaseDnMonitors() Deregisters monitoring entries associated to the base DNs handled by the monitored backend in the directory server.
protected String	getBackendType() Returns the local backend implementation type.
protected B	getLocalBackend() Returns the local backend associated with this backend.
void	registerBaseDnMonitors() Registers monitoring entries associated to the base DNs handled by the monitored backend in the directory server.
void	updateBaseDnMonitors() Updates the list of monitoring entries associated to the base DNs handled by the monitored backend in the directory server.

Methods inherited from class org.opends.server.api.MonitorProvider

configurationDnToMonitorDn, deregisterAll, getMonitorEntry, getMonitorInstanceDn, toString

Methods inherited from class java.lang.Object

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

Constructor Detail

LocalBackendMonitor

public LocalBackendMonitor(B backend)

Creates a new instance of this backend monitor provider that will work with the provided backend.

Parameters:

backend - The backend with which this monitor is associated.

Method Detail

computeMonitorInstanceDn

protected final Dn computeMonitorInstanceDn()

Description copied from class: MonitorProvider

Returns the monitor instance DN for this monitor provider.

Specified by:

computeMonitorInstanceDn in class MonitorProvider

Returns:

the monitor instance DN.

addMonitorObjectClassNames

protected void addMonitorObjectClassNames(Attribute ocAttr)

Description copied from class: MonitorProvider

Adds to the provided attribute the objectclass names that should be included in the monitor entry created from this monitor provider. This method should be implemented by child classes to make it easier to search for monitor entries of a specific type.

Specified by:

addMonitorObjectClassNames in class MonitorProvider

Parameters:

ocAttr - the objectClass attribute where to add the object class names

bindTo

public final void bindTo(MeterRegistry parent)

Description copied from class: MonitorProvider

.

Implementation considerations

Implementations MUST set the MonitorProvider.registry field by creating a new MeterRegistryHolder, and specifying the appropriate prefix for the dimensional model and also the hierarchical model if they are different. This can be done using a parameter on the constructor, or the MeterRegistryHolder.hierarchicalNamePrefix(String) method. Tags common to all metrics for this monitor provider can also be set using the MeterRegistryHolder.tag(String, String) method.

Attribute names are then registered by calling factory methods on the MonitorProvider.registry field.

Sample dummy implementation

(Please remove the comments when using this code as a template)

 
 public void bindTo(final MeterRegistry parent) {
     // create the MeterRegistryHolder wrapping OpenDJ's MeterRegistry
     registry = new MeterRegistryHolder("dimensional-name-prefix", parent)
              .tag("label", "dimension")
              .hierarchicalNamePrefix("hierarchical-name-prefix.dimension");

     // register the metrics against the wrapper
     registry.numberGauge("gauge", numberSupplier); // use lambdas or method references here
     timer = registry.timer("requests-submitted");
     // set a different name for the metric in cn=monitor, dimensional model and hierarchical model
     Gauge.doubleGauge(dimensionalName, supplier)
          .hierarchicalName(hierarchicalName)
          .tag(MeterRegistryHolder.TAG_ATTRIBUTE_NAME, "cn-monitor-name") // drop the "ds-mon-" prefix here
          .register(registry);
     // this gauge will only output to cn=monitor based monitoring endpoints
     registry.monitoringGauge("only-visible-in-cn-monitor", supplier);
 }
 
 

Specified by:

bindTo in interface MeterBinder

Specified by:

bindTo in class MonitorProvider

getBackendType

protected String getBackendType()

Returns the local backend implementation type.

Returns:

A string used in this monitor provider's MeterRegistry representing the local backend type.

addAdditionalMetrics

protected void addAdditionalMetrics()

Adds additional metrics specific to the local backend implementation in this monitor provider's MeterRegistry.

The default implementation is to do nothing.

getLocalBackend

protected final B getLocalBackend()

Returns the local backend associated with this backend.

Returns:

The local backend associated with this backend.

registerBaseDnMonitors

public final void registerBaseDnMonitors()

Registers monitoring entries associated to the base DNs handled by the monitored backend in the directory server.

deregisterBaseDnMonitors

public final void deregisterBaseDnMonitors()

Deregisters monitoring entries associated to the base DNs handled by the monitored backend in the directory server.

updateBaseDnMonitors

public final void updateBaseDnMonitors()

Updates the list of monitoring entries associated to the base DNs handled by the monitored backend in the directory server.