10.2. Using Resource Proxies

The JBoss ON CLI interacts directly with the JBoss ON server through remote APIs for handling resource objects and through the domain APIs for tasks like searches.
The JBoss ON CLI itself provides another API layer that can make it easier to perform common operations. The CLI can create a resource proxy object in the CLI, and then that object uses the classes available in the ProxyFactory to interact with the remote and domain API.
One thing to remember is that proxy resources still use the remote and domain API. The proxy API just provides a simpler and clearer API on top of the remote and domain APIs that can make it easier to script many operations.
The ProxyFactory is available to the JBoss ON CLI in interactive mode or when using a script file. It is also available to server scripts, such as scripts used for alerting.
The ProxyFactory gets information about a resource, which is identified in the getResource() method with the resource's ID number.
At its simplest, ProxyFactory can return a complete summary of information about the specified resource, such as its current monitoring data and traits, resource name, available metrics, available operations, content information, and child inventory, all dependent on the resource type. For example:
rhqadmin@localhost:7080$ ProxyFactory.getResource(10001)
                               OSName: Linux
                            OSVersion: 2.6.32-220.4.1.el6.x86_64
                         architecture: x86_64
                         contentTypes: {rpm=RPM File}
                          createdDate: Mon Feb 06 11:24:50 EST 2012
                          description: Linux Operating System
                     distributionName: Red Hat Enterprise Linux Server
                  distributionVersion: release 6.2 (Santiago)
                           freeMemory: 16.7GB
                        freeSwapSpace: 25.6GB
                             hostname: server.example.com
                                   id: 10001
                                 idle: 70.8%
                         measurements: [Wait Load, Used Memory, System Load, Distribution Version, Total Memory, OS Name, Free Memory, Hostname, Architecture, Distribution Name, Idle, Total Swap Space, Used Swap Space, User Load, OS Version, Free Swap Space]
                         modifiedDate: Mon Feb 06 11:24:50 EST 2012
                                 name: server.example.com
                           operations: [viewProcessList, cleanYumMetadataCache, manualAutodiscovery]
        pluginConfigurationDefinition: ConfigurationDefinition[xml:id=10009, name=Linux]
                         resourceType: Linux
                           systemLoad: 0.0%
                          totalMemory: 23.5GB
                       totalSwapSpace: 25.6GB
                           usedMemory: 6.8GB
                        usedSwapSpace: 0.0B
                             userLoad: 15.8%
                              version: Linux 2.6.32-220.4.1.el6.x86_64
                             waitLoad: 0.0%
To truly manage resources, the ProxyFactory creates a resource proxy object.

Example 10.3. Defining a Platform Proxy Resource

var rhelServerOne = ProxyFactory.getResource(10001)
The methods that are available to a resource proxy depend on the resource type and the resource's own configuration. There are five major types of operations that can be performed on resource proxies:
  • Viewing basic information about the resource, such as its children
  • Getting measurement information
  • Running operations
  • Changing resource and plug-in configuration
  • Updating and retrieving content
For each resource type, methods are exposed which allow you to find and use specific information about the resource. Additionally, the proxy API includes "shortcuts" which provide one-word methods, without requiring any parameters, to perform common remote API tasks, like getting monitoring information.
The proxy API for common resource types is listed in Section 9.8, “Methods Available to Proxy Resources”.
Use tab-complete in the interactive CLI to find the specific methods available for a resource type or to get the method signatures for individual methods.

Example 10.4. Viewing a Resource's Children

ProxyFactory has a method for all proxy objects, children, which lists all of the children for the proxy resource.
var rhelServerOne = ProxyFactory.getResource(10001)

rhqadmin@localhost:7080$ platform.children
Array of org.rhq.bindings.client.ResourceClientProxy
[10027] Bundle Handler - Ant (Ant Bundle Handler::AntBundlePlugin)
[10026] CPU 6 (CPU::Platforms)
[10025] CPU 0 (CPU::Platforms)
[10024] CPU 5 (CPU::Platforms)
[10023] CPU 1 (CPU::Platforms)
[10022] CPU 4 (CPU::Platforms)
[10021] CPU 2 (CPU::Platforms)
[10020] CPU 3 (CPU::Platforms)
[10019] CPU 7 (CPU::Platforms)
[10018] /boot (File System::Platforms)
[10017] / (File System::Platforms)
[10016] /dev/shm (File System::Platforms)
[10015] /home (File System::Platforms)
[10014] eth1 (Network Adapter::Platforms)
[10013] eth2 (Network Adapter::Platforms)
[10012] eth0 (Network Adapter::Platforms)
[10011] lo (Network Adapter::Platforms)
[10004] postgres (Postgres Server::Postgres)
[10003] AS server.example.com RHQ Server (JBossAS Server::JBossAS)
[10002] RHQ Agent (RHQ Agent::RHQAgent)

Example 10.5. Viewing Resource Metrics

ProxyFactory provides a set of shortcut metrics for each individual measurement for a resource type. This corresponds to the findLiveData() method in the remote API, but it is much easier to get monitoring information quickly and it is simpler to identify what metrics are available.
To get a single measurement value, use the method for that resource type. (Get a list of all methods for a proxy object using tab-complete.)
var jbossas = ProxyFactory.getResource(14832)
rhqadmin@localhost:7080$ jbossas.JVMTotalMemory
                name: JVM Total Memory
        displayValue: 995.3MB
	description: The total amount of memory currently available in the app server JVM for current and fut...
Alternatively, simply get a list of metrics with their current values using the measurements method:
var rhelServerOne = ProxyFactory.getResource(10001)

rhqadmin@localhost:7080$ rhelServerOne.measurements
Array of org.rhq.bindings.client.ResourceClientProxy$Measurement
name                 displayValue                         description
Wait Load            0.0%                                 Percentage of all CPUs waiting on I/O
Used Memory          6.3GB                                The total used system memory
System Load          0.0%                                 Percentage of all CPUs running in system mode
Distribution Version release 6.2 (Santiago)               version of the Linux distribution
Total Memory         31.4GB                               The total system memory
OS Name              Linux                                Name that the operating system is known as
Free Memory          25.2GB                               The total free system memory
Hostname             server.example.com                   Name that this platform is known as
Architecture         x86_64                               Hardware architecture of the platform
Distribution Name    Red Hat Enterprise Linux Server      name of the Linux distribution
Idle                 92.6%                                Idle percentage of all CPUs
Total Swap Space     33.6GB                               The total system swap
Used Swap Space      0.0B                                 The total used system swap
User Load            16.7%                                Percentage of all CPUs running in user mode
OS Version           2.6.32-220.4.2.el6.x86_64            Version of the operating system
Free Swap Space      33.6GB                               The total free system swap
16 rows

Example 10.6. Running Operations on a Proxy

ProxyFactory has a shortcut method for every operation available for a resource.
First, get the list of operations available for the resource type using the operations method:
var rhelServerOne = ProxyFactory.getResource(10001)

rhqadmin@localhost:7080$ rhelServerOne.operations
Array of org.rhq.bindings.client.ResourceClientProxy$Operation
name                  description
viewProcessList       View running processes on this system
cleanYumMetadataCache Deletes all cached package metadata
manualAutodiscovery   Run an immediate discovery to search for resources
3 rows
Then, run the given operation method.
rhqadmin@localhost:7080$ rhelServerOne.viewProcessList();
Invoking operation viewProcessList
Configuration [11951] - null
  processList [305] {
pid   name                                        size       userTime kernelTime
1     init                                        19865600   150      10050
26285 httpd                                       214618112  90       80
26286 httpd                                       214618112  90       80
26288 httpd                                       214618112  110      70
26289 httpd                                       214618112  90       80
27357 java                                        4734758912 1289650  373890
30458 postgres                                    218861568  1820     27440
30460 postgres                                    180985856  1210     5330
30462 postgres                                    218984448  13080    42200
30463 postgres                                    218861568  3970     26940
30464 postgres                                    219328512  10600    15320
30465 postgres                                    181407744  18680    78760
30482 httpd                                       185905152  1660     7520
32410 bash                                        108699648  0        10
32420 java                                        6024855552 3890240  669810
305 rows

Example 10.7. Changing Configuration Properties

If the resource type supports resource configuration editing or if the resource type has plug-in connection properties, then the resource proxy has methods — editResourceConfiguration() and editPluginConfiguration(), respectively — to edit those properties.
The current configuration can be printed using the get*Configuration). For example, for the plug-in configuration:
var rhelServerOne = ProxyFactory.getResource(10001)			 
rhqadmin@localhost:7080$ rhelServerOne.getPluginConfiguration()
Configuration [10793] - null
  metadataCacheTimeout = 1800
  enableContentDiscovery = false
  yumPort = 9080
  enableInternalYumServer = false
  logs [0] {
The edit*Configuration() method brings up a configuration wizard that goes through all of the properties individually and prompts to keep or change each value. The properties are even grouped according to the same organization that the JBoss ON web UI uses. For example:
rhqadmin@localhost:7080$ rhelServerOne.editPluginConfiguration();
Non-Grouped Properties:
Group: Content
Group: Event Logs
[R]eview, [E]dit, Re[V]ert [S]ave or [C]ancel:
After each group, you have the option to revert or save the changes. Once the changes are saved, they are immediately updated on the JBoss ON server.
Keys Action
return Selects the default or existing value for a property.
ctrl-d The same as selecting the unset checkbox in the configuration UI.
ctrl-k Exits the configuration wizard.
ctrl-e Displays the help description for the current property.

Example 10.8. Managing Content on Resources

Some types of resources have content associated with them. These are typically EAR or WAR resources within an application server. The content file actually associated with that EAR/WAR resource is called backing content. These are usually JARs.
This content can be updated or downloaded from the resource.
To retrieve backing content (meaning, to download the JAR/EAR/WAR file), specify the filename and file path on the application server. For example:
var contentResource = ProxyFactory.getResource(14932)
To update the content for the resource, use the updateBackingContent method and specify the filename with the path on the application server to put the content and the version number of the content. For example:
contentResource.updateBackingContent("/resources/current/new.war", "2.0")