I wonder why the firmware image/5/0/0 CoAP method is POST.

[JeongByungYeol]

Hello
Here's a question.

http://www.openmobilealliance.org/release/LightweightM2M/V1_2-20201110-A/HTML-Version/OMA-TS-LightweightM2M_Transport-V1_2-20201110-A.html
In this document, Write selects PUT and POST.
PUT: Replacement
POST: Partial update for multi-instance resources only »/{Object ID}/{Object instance ID}/{Resource ID}
It says like this.

Send firmware images on firmware update
http://www.openmobilealliance.org/release/LightweightM2M/V1_2-20201110-A/HTML-Version/OMA-TS-LightweightM2M_Core-V1_2-20201110-A.html#Figure-E62-1-Example-of-a-LwM2M-Server-pushing-a-firmware-image-to-a-LwM2M-client

The firmware object is Single Instance.
In the example above, why was it delivered in post format?

[sbernard31]

My guess this is a specification error.
(Not the first time there is error in examples, some of them are reported for several years and still not fixed 😞 #281)

Reading http://www.openmobilealliance.org/release/LightweightM2M/V1_2-20201110-A/HTML-Version/OMA-TS-LightweightM2M_Transport-V1_2-20201110-A.html#6-4-4-0-644-Device-Management-and-Service-Enablement-Interface

You can see that POST on /{Object ID}/{Object Instance ID}/{Resource ID} is :

• either an EXECUTE request
• or a WRITE (Partial Update) for Multiple-Instance Resources

[mojanm]

Agreed, it should be PUT and not POST.
Another minor point being that it's legacy from v1.0.x where a single spec covered both Core and Transport. From v1.1 the Core Spec is meant to be Transport agnostic. Therefore, technically no explicit example should use CoAP methods or any other binding??