[Automotive] Sandboxing for System Installed Application

[Juergen Ryannel]

Hi,

I’m just looking at the patch for Sandboxing support for QmlLive (see https://codereview.qt-project.org/#/c/168747).

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Allow receiving updates with read only workspace
Storing updates in a writable overlay is useful when the application is
installed as a system application.
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This should be only be useful if you create a custom live enabled runtime which is installed on a device (for example a tablet) and is not allowed to write into its installed folder. In this case it need to find a writeable place for it’s data. Correct?
Or is it more the use case that there is a read-only workspace on a remote device and still we would like to update the user interface?


So we could either lookup a temporary folder or ask QStandardPaths for a writeable location. In both cases the implementation makes a choice. 
Personally I would like to see that there is a default strategy to find a writeable workspace location, which is not inside the implementation but can be set onto the livenode in case something is not writeable.

If the workspace is read-only we could also copy the workspace or as it proposed in the patch to use a url interceptor to overwrite the target case by case.

Can someone elaborate what is the exact use case here? And then I will create a JIRA issue for this to better understand which problem we try to solve. 

Thanks

/ jryannel