[Sugar-devel] Firefox and html activities

[Daniel Narvaez]

Hello,

I just realized that the current Firefox OS architecture looks perfect
for our purpouses. It's pretty well documented here

https://wiki.mozilla.org/B2G/Architecture

In short

* gonk. The base OS. Kernel, network management...
* b2g. Analogous to a web browser, A single window which can run
multiple webapps, each in it's own process.
* aurora. The UX, as a collection of webapps. There is also an
extension used only for debugging, but it proves that extensions works
there which is important for us.

I can think of two main ways we could base our webapps on this. One
blue sky the other more realistic and useful in the short time.

# Common

We don't need gonk. Our base system is just a normal Linux
distribution, with a few sugar specific services, datastore and
collaboration comes to mind.

We use b2g as provided by upstream. If we need to make changes they
have to be submitted to mozilla. This ensures we don't have to fork
anything with the associated maintenance costs. Note that b2g already
runs on a desktop just fine.

We load an extension which interacts with our own system services.

# Blue sky

We replace aurora completely with out own set of web apps,
specifically written for sugar, using the sugar-html js (graphics,
datastore, collaboration...). The shell UI components (home, frame...)
are also part of a webapp, as is window management.  Native apps are
not supported.

# Realistic

We run b2g inside sugar. The shell talks with the extension to get a
list of installed and running web activities to display in the home,
to launch them, to switch to them as required. It brings up the b2g
window when activating one of the webapps and so on.
Most of sugar is still made of native apps, but it's possible to start
writing web activities.

# From realistic to blue sky

There are possible variations in middle.

* Native activities might be wrapped into webapps using GDK Broadway

http://developer.gnome.org/gtk3/3.3/gtk-broadway.html

This would allow to get rid of the native sugar shell without
completely preventing native activities (of course non-gtk activities
would not work). It could be an intermediate step or could be the
final target if we decide providing some kind of native activities
support is important.

* Web applications which are not designed for sugar could be part of
our set of core activities.

* Parts of the shell could start to be ported to webapps gradually.


I'm pretty excited about this, I don't see particular roadblocks. I
have not investigated very deeply yet though, I might find them (or
you might!), let's see :)
It's nice because in principle it doesn't require any heavy or non
upstreamable mozilla patching. It gives us access to all the stuff
mozilla is developing for webapps. And it allows a smooth transition
from the current architecture.