org.opends.server.api

Class MonitorProvider

java.lang.Object

org.opends.server.api.MonitorProvider

All Implemented Interfaces:

MeterBinder

Direct Known Subclasses:

DataServerHandler, EntryCache, HealthStatusMonitorProvider, JvmMonitorProvider, KeyManagerProvider.CertificateMonitor, LocalBackendMonitor, ReplicationServerDomain, ReplicationServerHandler

@PublicAPI(stability=VOLATILE,
           mayExtend=true)
public abstract class MonitorProvider
extends Object
implements MeterBinder

This class defines the set of methods and structures that must be implemented by a Directory Server module that can provide usage, performance, availability, or other kinds of monitor information to clients.

Field Summary

Fields

Modifier and Type	Field and Description
protected MeterRegistryHolder	registry The possibly null meter registry holder.

Constructor Summary

Constructors

Constructor and Description
MonitorProvider()

Method Summary

Modifier and Type	Method and Description
protected abstract void	addMonitorObjectClassNames(Attribute objectClassAttribute) Adds to the provided attribute the objectclass names that should be included in the monitor entry created from this monitor provider.
abstract void	bindTo(MeterRegistry registry) .
protected abstract Dn	computeMonitorInstanceDn() Returns the monitor instance DN for this monitor provider.
static Dn	configurationDnToMonitorDn(Dn configDn) Convenience method for mapping a component's configuration DN to its equivalent monitoring DN.
void	deregisterAll() Deregisters all the meters registered by this monitor provider.
Entry	getMonitorEntry() Generates and returns a monitor entry based on the contents of this monitor provider.
Dn	getMonitorInstanceDn() Returns the DN of this monitor provider.
String	toString()

Methods inherited from class java.lang.Object

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

Field Detail

registry

protected MeterRegistryHolder registry

The possibly null meter registry holder. When not-null, subclasses must set this field in the bindTo(MeterRegistry) method.

Constructor Detail

MonitorProvider

public MonitorProvider()

Method Detail

configurationDnToMonitorDn

public static Dn configurationDnToMonitorDn(Dn configDn)

Convenience method for mapping a component's configuration DN to its equivalent monitoring DN.

For example, a component with the name cn=LDAP,cn=Connection Handlers,cn=config will be mapped to cn=LDAP,cn=Connection Handlers,cn=monitor.

Parameters:

configDn - The component's configuration DN.

Returns:

The equivalent monitor DN.

getMonitorInstanceDn

public final Dn getMonitorInstanceDn()

Returns the DN of this monitor provider. It should be unique among all monitor providers, including all instances of the same monitor provider.

Returns:

The DN of this monitor provider.

computeMonitorInstanceDn

protected abstract Dn computeMonitorInstanceDn()

Returns the monitor instance DN for this monitor provider.

Returns:

the monitor instance DN.

addMonitorObjectClassNames

protected abstract void addMonitorObjectClassNames(Attribute objectClassAttribute)

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.

Parameters:

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

bindTo

public abstract void bindTo(MeterRegistry registry)

.

Implementation considerations

Implementations MUST set the 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 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

deregisterAll

public void deregisterAll()

Deregisters all the meters registered by this monitor provider.

getMonitorEntry

public Entry getMonitorEntry()

Generates and returns a monitor entry based on the contents of this monitor provider.

Returns:

The monitor entry generated from the information of this provided monitor provider.

toString

public String toString()

Overrides:

toString in class Object