Hello,

Currently, D-Bus interface and bus name namespaces are named in accordance with the Java-like reverse-domain-name naming scheme, e.g. org.freedesktop.dbus.myinterface.

Interfaces and bus names use separate namespaces - that is, an interface named "org.a.b.c" has different semantics from a bus named "org.a.b.c" (for obvious reasons: its two different things).

On the Web (e.g. in XML and RDF), however, the URI namespace is typically used, e.g. http://mynamespace.org/subspace/. Many W3C standards, such as RDF and SPARQL, only operate upon the URI namespace.

In order to bridge these technologies with D-Bus resources (interfaces, buses etc.), I would like to propose a universal mapping between the standard D-Bus namespace and the URI namespace (based on suggestions from Simon McV and Matthew Johnson on #dbus) as follows:

(The exact mapping paths can be adjusted a bit if desired, but this is the basic idea)

For interface names, a.b.c... maps into http://dbus.freedesktop.org/interface/a.b.c...

For bus names, a.b.c... maps into http://dbus.freedesktop.org/bus/a.b.c...

For methods, method d of interface a.b.c maps into http://dbus.freedesktop.org/method/a.b.c/d

For signals, signal d of interface a.b.c maps into http://dbus.freedesktop.org/signal/a.b.c/d

For properties, property d of interface a.b.c maps into http://dbus.freedesktop.org/property/a.b.c/d

For arguments, argument e of method d of interface a.b.c maps into http://dbus.freedesktop.org/method/a.b.c/d#e argument e of signal d of interface a.b.c maps into http://dbus.freedesktop.org/signal/a.b.c/d#e

This mapping would allow e.g. XML documents and RDF graphs to refer to D-Bus resources such that you for instance could attach RDF semantics to a D-Bus interface. For instance, you would be able to assert that D-Bus interface org.a.b.c (<http://dbus.freedesktop.org/bus/org.a.b.c>) is a RDF/S subclass of interface org.a.b  (<http://dbus.freedesktop.org/bus/org.a.b>), or you might define a mapping from one set of methods into another set of methods, etc. The possibilities are as vast as the meaning of the word 'semantics'.

The mapping as proposed above would require approval from the owners of dbus.freedesktop.org and ideally a little textual description of each namespace available for retrieval at each (dereferenced) root URI path (http://dbus.freedesktop.org/interface/, http://dbus.freedesktop.org/bus/ etc.), for the mapping scheme to be deemed canonical.

What do you think?

Regards,

-- Anders Feder <lists.anders@feder.dk>