Framework or app?

[Mark Shuttleworth]

On 21/01/15 00:03, Ake Hedman wrote:
> I am the maintainer of the IoT/m2m framework VSCP & Friends
> (http://www.vscp.org) and I just found Snappy today and is really
> impressed but also a bit confused. VSCP and friends is a daemon, some
> developer libs and some utilities and some drivers written in c/c++
> which abstracts hardware connected to the system. The daemon expose a
> number of interfaces to the world which in turn can be used to control
> the connected hardware. Drivers are used to abstract hardware into a
> common model that lets everything be configured in a common way, etc,
> etc.
>
> Today a new driver is installing a piece of code with dependencys and
> then the system needs to setup a configuration for it specific to that
> system. Something that Snappy looks like a perfect candidate to do. My
> confusion comes from where a system like ours fit. Is it all supposed
> to go in a Snappy App and in that case how do I make it a package. Or
> should something like this be separated in two parts making VSCP a
> framework and the drivers, ui, etc that interface it all snappy apps.
> And in that case how do I make a framework for the core? Can I do
> that? Am I allowed to do that?

Hi Ake

Welcome! You're on the right track, let me clarify a few things:

 * A "snappy framework" is a snappy app / package that has extra
privileges. Normal snappy apps are contained - they live entirely inside
a fixed set of directories where they have their code and data, they
cannot see or talk to anything else. A framework gets a hand-written
security profile that allows it to "do more". Mainly that is useful for
providing access to a shared resource. It sounds like VSCP is a perfect
candidate for a framework.

 * There is a "hardware" layer that is device-specific. Some of what you
want may best to be encoded there by the device manufacturer. For
example, if you need to have specific pieces of hardware declared for
use by your framework, it would be appropriate to structure that as part
of the device description story. That part is newest so best to chat
with folks like Loic Minier about what you think you'd need at this level.

The folks on this list can get you started on turning VSCP into a snappy
framework. Would suggest you begin by working on standard snappy
packaging, since the mechanisms are identical for apps and frameworks.
Then we can create the custom security profile for your framework and
handle the additional frameworky bits. Once your framework is published,
apps can declare it as a dependency and it will be installed for them.

Mark