org.rhq.modules.plugins.jbossas7.jmx

Class ApplicationMBeansDiscoveryComponent

java.lang.Object

org.rhq.modules.plugins.jbossas7.jmx.ApplicationMBeansDiscoveryComponent

All Implemented Interfaces:

ResourceDiscoveryComponent<BaseComponent<?>>

public class ApplicationMBeansDiscoveryComponent
extends Object
implements ResourceDiscoveryComponent<BaseComponent<?>>

Discovery class for the container ApplicationMBeansComponent component class.

Custom plugin setup

This class is not declared in the AS7 plugin descriptor. It is a tool that that plugin developers may use while writing their own plugin to monitor their application MBeans.

The custom plugin must:

• depend on the AS7 plugin and re-use its classes (useClasses attribute set to true in the plugin descriptor);
• embed the JMX plugin as a library.

The resource type using this class (or a subclass of this class) as a discovery component must indicate which type of server it runs inside. It may be either a JBossAS7 Standalone Server or a Managed Server.

Plugins authors are required to provide a resource key and name and mayprovide a resource description and version by declaring plugin configuration properties of the following names:

• ApplicationMBeansDiscoveryComponent.PluginConfigProps.NEW_RESOURCE_KEY
• ApplicationMBeansDiscoveryComponent.PluginConfigProps.NEW_RESOURCE_NAME
• ApplicationMBeansDiscoveryComponent.PluginConfigProps.NEW_RESOURCE_DESCRIPTION
• ApplicationMBeansDiscoveryComponent.PluginConfigProps.NEW_RESOURCE_VERSION

Alternatively, they can subclass create a subclass of this discovery component and override one/some/all of the following methods:

• getNewResourceKey(org.rhq.core.domain.configuration.Configuration)
• getNewResourceName(org.rhq.core.domain.configuration.Configuration)
• getNewResourceDescription(org.rhq.core.domain.configuration.Configuration)
• getNewResourceVersion(org.rhq.core.domain.configuration.Configuration)

Auto-discovery

By default, application MBeans will be searched with an EMS query defined in the plugin descriptor by the ApplicationMBeansDiscoveryComponent.PluginConfigProps.BEANS_QUERY_STRING plugin-config property.
It is also possible to define the query string in a subclass overriding the getBeansQueryString(org.rhq.core.domain.configuration.Configuration) method.

Plugin developers can implement their custom MBeans lookup method in a subclass overriding the hasApplicationMBeans(org.rhq.core.domain.configuration.Configuration, org.mc4j.ems.connection.EmsConnection) method.

JMX host and port discovery

The JMX server host will be detected by looking at the top level server resource plugin configuration (StandaloneASComponent and HostControllerComponent). The JMX port detection mechanism depends on the parent resource.

On standalone servers

In standalone mode, the discovery component will look at the management port defined in the parent StandaloneASComponent plugin configuration and add the value STANDALONE_REMOTING_PORT_OFFSET.

On managed servers

In domain mode, the discovery component will use '4447' plus the port offset of the managed server.

Authentication

JMX connectivity on AS7 and EAP6 requires authentication and standalone and managed servers behaviors differ.

On standalone servers

In standalone mode, the server will use the ManagementRealm, just as for HTTP management interface authentication. Consequently, this class will pick up the credentials of the management user defined in the plugin configuration of the parent server resource (StandaloneASComponent).

In other words, plugin authors have nothing to do.

On managed servers

In domain mode, the server will use the ApplicationRealm. Consequently, there is no way for the discovery component to discover credentials automatically and it will use "rhqadmin:rhqadmin" by default.

When working with managed servers, plugin developers should subclass the discovery component and override the getCredentialsForManagedAS() method. For example, an implementation could lookup the credentials in a text file.

Plugin descriptor example

     <plugin
         name="MyappMBeansPlugin"
         displayName="Myapp MBeans Plugin"
         package="com.myapp.services.plugin"
         xmlns="urn:xmlns:rhq-plugin"
         xmlns:c="urn:xmlns:rhq-configuration">

       <depends plugin="JBossAS7" useClasses="true"/>

       <service name="Myapp Services"
                discovery="org.rhq.modules.plugins.jbossas7.jmx.ApplicationMBeansDiscoveryComponent"
                class="org.rhq.modules.plugins.jbossas7.jmx.ApplicationMBeansComponent"
                description="Container for Myapp Services"
                singleton="true">

         <runs-inside>
           <!-- The type of the server the application is running on -->
           <parent-resource-type name="JBossAS7 Standalone Server" plugin="JBossAS7"/>
           <parent-resource-type name="Managed Server" plugin="JBossAS7"/>
         </runs-inside>

         <plugin-configuration>
           <c:simple-property name="beansQueryString" readOnly="true" default="myapp:service=*"/>
           <c:simple-property name="newResourceKey" readOnly="true" default="myappServices"/>
           <c:simple-property name="newResourceName" readOnly="true" default="Myapp Services"/>
           <c:simple-property name="newResourceDescription" readOnly="true" default="Container for Myapp Services"/>
         </plugin-configuration>

         <!--
           ApplicationMBeansComponent can be the parent of any JMXComponent (JMX plugin). For example, it's possible
           to monitor a MBean with no line of Java code thanks to the MBeanResourceComponent facility. Plugin authors
           only have to configure metrics (mapped to MBeans attributes) and operations (MBeans operations).
         -->
         <service name="HelloService" discovery="org.rhq.plugins.jmx.MBeanResourceDiscoveryComponent"
                  class="org.rhq.plugins.jmx.MBeanResourceComponent" singleton="true">
           <plugin-configuration>
             <c:simple-property name="objectName" default="myapp:service=HelloService" readOnly="true"/>
           </plugin-configuration>
           <operation name="helloTo">
             <parameters>
               <c:simple-property name="p1" displayName="somebody" type="string" required="true"/>
             </parameters>
             <results>
               <c:simple-property name="operationResult" type="string"/>
             </results>
           </operation>
         </service>

       </service>

     </plugin>
 

Author:

Thomas Segismont

See Also:

ApplicationMBeansComponent

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	ApplicationMBeansDiscoveryComponent.PluginConfigProps

Constructor Summary

Constructors

Constructor and Description
ApplicationMBeansDiscoveryComponent()

Method Summary

Methods

Modifier and Type	Method and Description
Set<DiscoveredResourceDetails>	discoverResources(ResourceDiscoveryContext<BaseComponent<?>> context)
protected String	getBeansQueryString(org.rhq.core.domain.configuration.Configuration pluginConfig) The EMS query string chosen when using the default implementation of hasApplicationMBeans(org.rhq.core.domain.configuration.Configuration, org.mc4j.ems.connection.EmsConnection).
protected String[]	getCredentialsForManagedAS() Default implementation of the credentials lookup for JMX authentication against managed servers (domain mode).
protected String	getNewResourceDescription(org.rhq.core.domain.configuration.Configuration pluginConfig)
protected String	getNewResourceKey(org.rhq.core.domain.configuration.Configuration pluginConfig)
protected String	getNewResourceName(org.rhq.core.domain.configuration.Configuration pluginConfig)
protected String	getNewResourceVersion(org.rhq.core.domain.configuration.Configuration pluginConfig)
protected boolean	hasApplicationMBeans(org.rhq.core.domain.configuration.Configuration pluginConfig, org.mc4j.ems.connection.EmsConnection emsConnection) Indicates if a managed server or a standalone server has application MBeans.
static org.mc4j.ems.connection.EmsConnection	loadEmsConnection(org.rhq.core.domain.configuration.Configuration pluginConfig) Creates a new EmsConnection object.

Methods inherited from class java.lang.Object

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

Constructor Detail

ApplicationMBeansDiscoveryComponent

public ApplicationMBeansDiscoveryComponent()

Method Detail

discoverResources

public Set<DiscoveredResourceDetails> discoverResources(ResourceDiscoveryContext<BaseComponent<?>> context)
                                                 throws Exception

Specified by:

discoverResources in interface ResourceDiscoveryComponent<BaseComponent<?>>

Throws:

Exception

hasApplicationMBeans

protected boolean hasApplicationMBeans(org.rhq.core.domain.configuration.Configuration pluginConfig,
                           org.mc4j.ems.connection.EmsConnection emsConnection)

Indicates if a managed server or a standalone server has application MBeans. This implementation searches MBeans with an EMS query string.

Parameters:

pluginConfig - - the plugin configuration object for the ApplicationMBeansComponent that may be created

emsConnection - - an active emsConnection which can be used to communicate with the server

Returns:

true if application MBeans were detected, false otherwise

getCredentialsForManagedAS

protected String[] getCredentialsForManagedAS()

Default implementation of the credentials lookup for JMX authentication against managed servers (domain mode).

Returns:

an array of two elements, the first being the username and the second the password

getBeansQueryString

protected String getBeansQueryString(org.rhq.core.domain.configuration.Configuration pluginConfig)

The EMS query string chosen when using the default implementation of hasApplicationMBeans(org.rhq.core.domain.configuration.Configuration, org.mc4j.ems.connection.EmsConnection).

Parameters:

pluginConfig - - the plugin configuration object for the ApplicationMBeansComponent that will be created

Returns:

an EMS query string

getNewResourceKey

protected String getNewResourceKey(org.rhq.core.domain.configuration.Configuration pluginConfig)

Parameters:

pluginConfig - - the plugin configuration object for the ApplicationMBeansComponent that will be created

Returns:

the new resource key

getNewResourceName

protected String getNewResourceName(org.rhq.core.domain.configuration.Configuration pluginConfig)

Parameters:

pluginConfig - - the plugin configuration object for the ApplicationMBeansComponent that will be created

Returns:

the new resource name

getNewResourceDescription

protected String getNewResourceDescription(org.rhq.core.domain.configuration.Configuration pluginConfig)

Parameters:

pluginConfig - - the plugin configuration object for the ApplicationMBeansComponent that will be created

Returns:

the new resource description

getNewResourceVersion

protected String getNewResourceVersion(org.rhq.core.domain.configuration.Configuration pluginConfig)

Parameters:

pluginConfig - - the plugin configuration object for the ApplicationMBeansComponent that will be created

Returns:

the new resource version

loadEmsConnection

public static org.mc4j.ems.connection.EmsConnection loadEmsConnection(org.rhq.core.domain.configuration.Configuration pluginConfig)

Creates a new EmsConnection object.

Parameters:

pluginConfig - - a plugin configuration object of the ApplicationMBeansComponent

Returns:

a new EmsConnection object or null if connecting failed