iApps LX Processors¶
Since iApps® LX is an extension of iControl LX, you can logically assume that the actions of a processor correspond to HTTP methods. An iApps LX extension functions as a REST worker and typically uses the HTTP methods POST, PATCH, and DELETE. There are three basic types of processors for iApps LX:
- Configuration Processor
- Audit Processor
- Stats Processor
The configuration for these processors is included in the JAVA script code of the iApps LX RPM package.
About the Configuration Processor¶
The configuration (config) processor is a required part of the iApps LX. The config processor and the block’s state engine are inter-dependent as the config processor is the controller component that processes tasks so that the iApps LX state can be changed. A config processor handles changes, as well as deletions, to a configuration, by performing actions equivalent to a POST or DELETE method.
When you change the value of the state property (in the block instance) to BINDING, you cause the iApps LX state engine to activate the POST action. When you are deploying a configuration, the POST method is passed to the config processor. As part of the processing of deploying the configuration, the config processor changes the state to BOUND, or to ERROR if the deployment fails. In a similar manner, if you change the value of the state property (in the block instance) to UNBINDING, you cause the removal of a configuration. The iApps LX state engine activates the DELETE action, resulting in the change of state to UNBOUND. The communication between the config processor and the iApps LX block is done via an internal worker.
The configuration processor code is saved as part of the installed RPM in cd
/var/config/rest/iapps/. For more information on programming a config processor, see Programming an iApps LX Config Processor
About the Audit Processor¶
The audit processor is an optional part of the iApps LX JAVA script code. It identifies any configuration conflicts between an iApps LX block instance and another system configuration. By defining the audit policy (NOTIFY_ONLY, ENFORCE_CONFIGURED, ACCEPT_FOUND) the system knows if to accept or reject any conflicts. For more information on programming an audit processor, see Programming an iApps LX Audit Processor.
About the Stats Processor¶
By default, basic health statistics are collected for iApps LX resources. The stats processor can be customized to collect additional statistics as can be configured in the iApps LX JAVA script code. The stats processor reads statistics and system health information and writes the data to a specific endpoint. For more information on programming a stats processor, see Programming an iApps LX Stats Processor.