(Technical Details - Part 2) How to deploy 3rd party custom modules to LEAFOS devices

(Technical Details - Part 2) How to deploy 3rd party custom modules to LEAFOS devices

Deploying LEAFOS modules to LEAFOS devices

Once the module containing a System Extension or a Packaged Application is created (please refer to the Part 1 article here), it can be deployed to LEAFOS devices. This can be done locally from a USB mass storage device or a network server in the Files panel of the Files and Modules section of LEAFOS Setup GUI. The same can also be done remotely using NComputing’s PMC Endpoint Manager.


Deploying system extension modules

To deploy a system extension module, the module file which has been added to the device as Generic File in first step, needs to be selected as system extension module. This can be done locally in the Modules panel of the Files and Modules section of LEAFOS Setup GUI. The same can also be done remotely using NComputing’s PMC Endpoint Manager.


Once the system extension module has been deployed, the LEAFOS device needs to be rebooted for the changes to take effect. On next boot, the contents of the system extension module is laid over the LEAFOS root file system and appears to other system components as part of the base LEAFOS.

Recovering LEAFOS after deploying an erroneous system extension module

Deploying a system extension module with contents altering vital LEAFOS files can make the system unbootable. To recover from such situation, please power-cycle the device and keep pressing the [Esc] key as the device boots. When the bootloader (GRUB) menu appears, select the ‘NComputing LEAFOS(X86) Skip system extension modules mounting’ option. The system is then booted without the problematic system extension module. The device can now be reconfigured and the problem module removed.

Deploying packaged application modules

To make the application contained in packaged application module available to LEAFOS users, the packaged application module needs to be selected in custom application definition. Please refer to the next section for the details.

Defining custom applications

As stated at the beginning of this document, custom applications are a special type of local applications, where the application properties (the name, icon, executable command, etc.,) can be read from a deployed packaged application module (for packaged applications) or defined manually (for system applications). The custom applications can be defined in the Custom Application tab of the Local Applications section of LEAFOS settings. This can be done locally in LEAFOS Setup GUI or remotely using NComputing’s PMC Endpoint Manager.

Adding packaged applications

To add a packaged application, the following selections are necessary:

·         Application type: Packaged application

·         Packaged application file: Name of the Generic File uploaded to LEAFOS device and containing the packaged application module.


Adding system applications

To add a system application, the following selections and settings are necessary:

·      Application type: System application

·      Display name: Application name to be presented to the users on the Local Applications list.

·      Icon path: Path to a PNG file containing the custom application icon. Generic icon will be used when left empty.

·     Command path: Path to the executable file of the custom application.

·     Command parameters: Command line parameters to be passed to the executable file. If multiple parameters need to be passed, they need to be separated with semicolons.

·     Configuration paths: Semicolon-separated list of directories, where the custom application stores its configuration. With Guest Mode enabled, LEAFOS will delete those directories upon exit. With Guest Mode disabled, LEAFOS will link those directories to a persistent storage location.



Provisioning custom-application-specific parameters

Custom Applications which contain launcher programs can accept configuration parameters. The Manage application configuration option allows provisioning values for the named parameters understood by custom application launcher. Please refer to previous sections for the information about using custom application parameters in application launchers.



Accessing custom applications defined in LEAFOS

Once the custom applications are defined, they can be accessed by the user in Local Applications mode. Custom Applications appear on the list alongside the built-in local applications (Chromium browser, Microsoft Teams or Zoom client). Additionally, when the Enable Local Applications option is enabled in Connections settings of LEAFOS device operating in AVD Client or RDP Client (with RemoteApp support enabled) mode, the custom applications will appear on the list of published RDP or AVD resources.





See reference examples of packaged 'custom modules' from popular applications for LEAF OS devices: