Re: [core] Questions/comments on draft-ietf-core-dynlink-02

[Michael Koster <[e-mail]>]

To summarize, I recommend that we change 4.2 to specify using observe attributes as query parameters in the OBSERVE operation to which they apply.

We could optionally make them writeable as a single set of attributes to apply to all observations of that resource.

If we want to make the single set readable, we will need to add more specification. about the returned representation.

Best regards,

Michael


> On Mar 13, 2017, at 5:58 AM, Michael Koster <[e-mail]> wrote:
> 
> Hi Mojan,
> 
> I think this is the default behavior for OMA LWM2M using the "Write Attributes" operation. The effect is to provide a single set of notification parameters for all observe operations on that resource.
> 
> I believe that we improve on that pattern and allow each observe request to have its own attributes, set by including query parameters in the GET operation.
> 
> Section 4.2 also indicates that they are readable, but it's not clear to me how that would work? In what format are they returned, also as query parameters? These could be made readable (and updateable) througn a special CoRE Interface, but we would need to specify how the content format of these works vs. the content format of the resource state.
> 
> LWM2M could be described in this draft as a legacy pattern.
> 
> Does this make sense?
> 
> Best regards,
> 
> Michael
> 
> 
>> On Mar 10, 2017, at 2:52 AM, Mojan Mohajer <[e-mail] <mailto:[e-mail]>> wrote:
>> 
>> 2) Section 4.2 which covers resource observation attributes (pmin, pmax, st, …) states that that: …”These query parameters MUST be treated as resources that are read using GET and updated using PUT, and MUST NOT be included in the Observe request” ….
>> However, looking at newly added Annex A which provides observation examples, these observation attributes are passed as query parameters of a Get request with Observe option set to 0. There seems to be some contradiction between the text in section 4.2 and the example in Annex A.
>