Von: Dave Raggett [mailto:dsr@w3.org]
I would very much like to hear from the IG what exactly is meant by “URI mappings for non-resourceful protocols”.
Correct wording will be tricky on this one: A “resource is anything that can be identified by a URI”, but many protocols do not call their data endpoints a resource, but it is still possible to come up with URIs to identify and address them. Thus, “non-RESTful” might be a bit closer.
Anyhow, the intention is to define URIs that can address data elements (or “interaction” elements in TD terms) in IoT protocols that do not have URIs (yet), for instance, an attribute in GATT/BLE or a topic in MQTT. A URI is basically just a string that identifies the protocol through the scheme and then more information that can be used to encode protocol-specific addressing information.
When a client has the necessary protocol stack, it can contact the interaction element described by the TD through the URI directly. If not, it can pass this URI to a proxy (e.g., using the CoAP Proxy-URI option or HTTP proxying through the Request-Line), which will then make the request in that protocol on behalf of the client. This kind of proxy is application-agnostic (it does not know anthing about WoT, TD, and interactions, but only the two or more protocols).
Does the idea become clearer?
Best regards
Matthias