Difference between revisions of "Platform Team/Polyol"

Latest revision as of 08:16, 2 July 2012

Summary

A set of C libraries to help with coding non-Python Sugar activities.

Concepts

Glucose processes
Sugar core processes and dbus services.
DBus
All communication between glucose level and activity process goes via dbus.
Polyol
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:
- All libraries are written in Vala, i.e., based on pure GObjects, and could be used by non-python-based activities.
- 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 gtk+ (via gui).
Activity process
Regular activities would not use glucose directly, rather they would only access glucose through the Polyol level.

Components

All libraries are C based and could contain bindings for various programming languages. Libraries use the same sources tree.

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.

toolkit

Everything what developers need to start developing native sugar activities. Library depends on all other Polyol components and contains glue level code that simplify creating sugar activities from scratch. This library (and all its dependencies) is an analog of python based sugar-toolkit library.

Bindings for this library (in contrast with bindings for other Polyol components) could contain not only wrappers for library itself, but also particular language specific code that makes process of creating sugar activities in this language more comfortable.

Build from sources

Install required dependencies

cmake >= 2.6
gee >= 0.5

Download last tarball.

Build it:

cd <sources-root> && cmake [-D<var-name>=<var-value>] . && make && make install

Useful cmake variables:

MAINTAINER_MODE, set to TRUE to recreate generated files, default is FALSE
CMAKE_C_FLAGS
CMAKE_INSTALL_PREFIX, default is /usr/local
PYTHON_SITEDIR, path within CMAKE_INSTALL_PREFIX to install python libraries, default is lib
COMPONENTS, ; separated list of components to build, default is all components
BINDINGS, ; separated list of bindings to build, default is all bindings

For each component, Polyol will install .pc file. So, after installing polyol, be sure that pkg-config will find .pc files e.g. setup PKG_CONFIG_PATH variable before using polyol.

Pitfalls

Python binding libraries cannot be linked with C libraries from sugar-toolkit.
Polyol names contain the sugar prefix to reuse sugar-artwork as-is.

Sources

Gitorious project.

@@ Line 1: / Line 1: @@
-<noinclude>
-{{TOCright}}
-</noinclude>
 == Summary ==
-Intermediate level [http://library.gnome.org/devel/gobject/stable/ GObject] based libraries group.
+A set of C libraries to help with coding non-Python Sugar activities.
-See [[Documentation Team/Services/Scalable development model|Scalable development model]] to learn more about the initial intentions of Polyol.
 == Concepts ==
@@ Line 13: / Line 7: @@
 [[File:polyol.png|500px]]
-==== Glucose processes ====
+* '''Glucose processes'''
+*: Sugar core processes and dbus services.
-Sugar core processes and dbus services.
+* '''DBus'''
+*: All communication between glucose level and activity process goes via dbus.
-==== DBus ====
+* '''Polyol'''
+*: Intermediate level libraries:
-All communication between glucose level and activity process goes via dbus.
+*:* Glucose compatibility libraries (ds, shell, collab) will support several (popular among sugar deployments) glucose releases
+*:* Other libraries are not tied to glucose directly
-==== Polyol group ====
+*: Key features:
+*:* All libraries are written in Vala, i.e., based on pure GObjects, and could be used by non-python-based activities.
-Intermediate level libraries:
+*:* 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 gtk+ (via ''gui'').
-* Glucose compatibility libraries (ds, shell, collab) will support several (popular among sugar deployments) glucose releases
+* '''Activity process'''
-* Other libraries are not tied to glucose directly
+*: Regular activities would not use glucose directly, rather they would only access glucose through the Polyol level.
-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 gtk+ (via ''gui'').
-==== Activity process ====
-Regular activities would not use glucose directly, rather they would only access glucose through the Polyol level.<br>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.
 == Components ==
-All libraries are C based and could contain bindings for various programming languages. Libraries use the same [http://git.sugarlabs.org/projects/polyol sources tree] but each component has its own 0install interface and versions (there will be a way to use entirely polyol as single package e.g. for GNU/Linux distribution needs since all benefits of separation vanishes in that case).
+All libraries are C based and could contain bindings for various programming languages. Libraries use the same [http://git.sugarlabs.org/projects/polyol sources tree].
-==== [[Activity_Team/Services/Env|env]] ====
+==== env ====
 Access to various sugar environment settings.
-==== [[Activity_Team/Services/Shell|shell]] ====
+==== shell ====
 Compatibility level library to sugar-shell.
-==== [[Activity_Team/Services/Collab|collab]] ====
+==== collab ====
 High level client API for what activity developers might need to code collab activities.
-==== [[Activity_Team/Services/Ds|ds]] ====
+==== ds ====
 High level client API to sugar-datastore.
-==== [[Activity_Team/Services/Gui|gui]] ====
+==== gui ====
 A set of first level GUI widgets to simplify process of activity creation.
-==== [[Activity_Team/Services/Toolkit|toolkit]] ====
+==== toolkit ====
 Everything what developers need to start developing native sugar activities. Library depends on all other Polyol components and contains glue level code that simplify creating sugar activities from scratch. This library (and all its dependencies) is an analog of python based sugar-toolkit library.
@@ Line 67: / Line 51: @@
 Bindings for this library (in contrast with bindings for other Polyol components) could contain not only wrappers for library itself, but also particular language specific code that makes process of creating sugar activities in this language more comfortable.
-== Build for non-0install usage ==
+== Build from sources ==
 Install required dependencies
@@ Line 73: / Line 57: @@
 * [http://live.gnome.org/Libgee gee] >= 0.5
-Download last [http://download.sugarlabs.org/services/polyol/ tarball].
+Download last [https://packages.sugarlabs.org/package/files?package=polyol&project=sdk tarball].
 Build it:
-  cd <sources-root> && cmake [-D<var-name>=<var-value>] . && make && make install
+  cd <sources-root> && cmake [<nowiki>-D<var-name>=<var-value></nowiki>] . && make && make install
 Useful cmake variables:
@@ Line 86: / Line 70: @@
 * ''COMPONENTS'', '';'' separated list of components to build, default is all components
 * ''BINDINGS'', '';'' separated list of bindings to build, default is all bindings
+For each component, Polyol will install ''.pc'' file. So, after installing polyol, be sure that ''pkg-config'' will find ''.pc'' files e.g. setup ''PKG_CONFIG_PATH'' variable before using polyol.
+== Pitfalls ==
+* Python binding libraries cannot be linked with C libraries from sugar-toolkit.
+*: Polyol names contain the {{Code|sugar}} prefix to reuse sugar-artwork as-is.
+== Sources ==
+* [http://git.sugarlabs.org/sdk/polyol Gitorious project].