Platform Team/Polyol

Summary

Intermediate level GObject based libraries group.

See Scalable development model to learn more about the initial intentions of Polyol.

Concepts

Glucose processes
Sugar core processes and dbus services.

DBus
All communication between glucose level and activity process goes via dbus.

Polyol group
Intermediate level libraries:

Glucose compatibility libraries (ds, shell, collab) will support several (popular among sugar deployments) glucose releases
Other libraries are not tied to glucose directly

Key features of this level:

All libraries are written in Vala, i.e., based on pure GObjects, and could be used by non-python-based activities.
Each Polyol component has its own release schedule, i.e., there are no Polyol official releases (it looks like in Gentoo).
Activities could use these libraries on separate basis e.g. activity could use recent gui (to get access to last UI widgets) and old version of ds (because activity was coded against this particular version and new version has backward compatibility breakage in API).
Activities (mostly not native sugar activities) could use only one library e.g. activity could use only ds library thus do not fetch additional dependencies like telepathy (via collab) and gtk+ (via gui).

Activity process
Regular activities would not use glucose directly, rather they would only access glucose through the Polyol level.
There is no need to code special activities, the sugar-toolkit API will be preserved, and activity developers will benefit because Polyol will support the recent sugar-toolkit API, e.g., they could use the new toolbars design even on Sugar 0.82.

Core libraries

All core libraries are C based and could contain bindings for various programming languages.

env

Access to various sugar environment settings.

shell

Compatibility level library to sugar-shell.

collab

High level client API for what activity developers might need to code collab activities.

ds

High level client API to sugar-datastore.

gui

A set of first level GUI widgets to simplify process of activity creation.

Programming language glue libraries

These are not C based but written in specific programming language libraries. They are glue level libraries that contain programming language specific code to start developing sugar activities. Libraries don't contain bindings for core, bindings are part of particular core library.

toolkit-python

Everything what developers need to start developing sugar activities in Python.