ObjectLink and Cbor Mapping

[iot-cloud]

Hi,

I am trying to implement the Client and Leshan Device Management Server to support the ObjectLink and Cbor to be used in the Device ExtDevInfo or LWM2m Software Management.

If I perform a read on ExtDevInfo or Package Settings, I expect a Cbor byte array. What do I do to implement ObjectLink into Cbor encoded byte array.

Has anyone attempt to do anything to map ObjectLink into Cbor and Cbor into ObjectLink?

Please share and guide me with some examples.

Thank in advanced.

Regards, hulk

Device
ExtDevInfo
R
Objlnk

LWM2M Software Management
Package Settings
RW
Objlnk

[sbernard31]

Currently, we only support LWM2M 1.0 and if I'm not wrong Cbor is only in 1.1.
We are thinking about LWM2M 1.1, and this is not impossible we begin to work on it at mid term.

Anyway, Leshan is pretty flexible about encoder/decoder so if you want to add or replace default decoder/encoder, you can !
To do that, just implements a LwM2mNodeDecoder or LwM2mNodeEncoder, you can start from DefaultLwM2mNodeDecoder or DefaultLwM2mNodeEncoder.
Then you can add your custom encode/decoder using LeshanBuilder.setEncoder and LeshanBuilder.setDecoder.

About ObjectLink, I'm not sure to understand what is currently missing ?

Don't forget to share your work with us ;)

[sbernard31]

(about LWM2M 1.1, if you want to share your thought about it : #563)

[iot-cloud]

Hi Bernard - the Leshan Gatekeeper. Thank for taking your time to explain.

There're few OMA IPSO Object specifications documented with the ObjLnk type in which is implemented into the ObjectLink Class in Leshan.

I believe that ObjectLink in the IPSO Object-1 is used to specify the "Relation" with other IPSO objects. The IPSO Object-1 also contains the PayLoad Attribute documented with the byte array described the cbor encoding.

Regards, hlkn

[sbernard31]

So you want support of ObjectLink with cbor encoding ?

I understood that your request for objectLink was a separated feature request and I didn't understand because it seems to me that ObjectLink is currently implemented in Leshan (for json and tlv format).

[sbernard31]

Could we close this issue ?

[cavenaghi9]

Hi Bernard, as you explained above, Leshan is pretty flexible to extend encoder/decoder, that is approach what I did. In addition, DefaultLwM2MNodeDecoder/DefaultLwM2MNodeEncoder, knownContentFormat in ContentFomat.java, and client-detail.html in leshan-server-demo component also need to be updated. If I want to share my work, is there any strategy of introducing third party dependency in Leshan, because of CBOR encoder/decoder right now are using open source library.

[sbernard31]

You can start by opening a PR.
You will need to sign eclipse CLA

[sbernard31]

So we can close this issue and we will continue the discussion in the PR.