[WoT+NGSI-LD] minutes - 14 April 2025

available at:
  https://www.w3.org/2025/04/14-wot-ngsi-ld-minutes.html


also as text below.

Thanks a lot for taking notes, Dave!

Kazuyuki

---
   [1]W3C

      [1] https://www.w3.org/


                             – DRAFT –
                            WoT and NGSI-LD

14 April 2025

   [2]Agenda. [3]IRC log.

      [2] https://www.w3.org/WoT/IG/wiki/WoT-NGSI-LD#April_14,_2025

      [3] https://www.w3.org/2025/04/14-wot-ngsi-ld-irc


Attendees

   Present
          Dave_Raggett, Franck_LE_GALL, Frederic_LE,
          Juanjo_Hierro, Kaz_Ashimura, Martin_Bauer,
          Michael_Koster, Michael_McCool, Zane_Durkin

   Regrets
          -

   Chair
          McCool

   Scribe
          draggett

Contents

    1. [4]Logistics
    2. [5]Minutes
    3. [6]Activities
         1. [7]Issue 18
         2. [8]PR 17
         3. [9]PR 14
         4. [10]Stakeholders
         5. [11]Examples of mapping between NGSI-LD Entity and WoT
            Thing

Meeting minutes

  Logistics

   The next meeting will be April 28

   McCool: I won't be as engaged with WoT as my role at Intel is
   changing.

   I can probably make the call twice a month

   We may be able to interest people in the Smart City group, Kaz
   can ask...

   Sebastian should be able to help out

  Minutes

   <kaz> [12]Mar-10

     [12] https://www.w3.org/2025/03/10-wot-ngsi-ld-minutes.html


   McCooll refers to his use case

   Some discussion on north bound APIs in relation to TDs

   We approve the minutes.

  Activities

   (for 14 April 2025)

   <jhierro1> Also Martin prepared a use case in form of PR. He
   will join later today

    Issue 18

   An outstanding question is how to map actions

   McCool: I'd like to walk us through what we mean by actions

   <kaz> [13]Issue 18 - Discuss Action Semantics

     [13] https://github.com/w3c/wot-ngsi-ld/issues/18


   We have an opportunity to align on what we mean by actions

   Juanjo: actions are not currently supported in NGSI-LD, but
   they are on the roadmap

   <kaz> [14]WoT Thing Description 1.1 REC - 5.3.1.4
   ActionAffordance

     [14] https://www.w3.org/TR/wot-thing-description11/#actionaffordance


   McCool: let's look at the current TD spec. This describes how
   to invoke a function, which may or may not change the state

   <jhierro1> but this is not a problem but an opportunity because
   actions then can be defined in NGSI-LD in a way keeping an eye
   how things can work together with WoT.

   A non-state changing function might for example change the
   units of measure

   The vocab term "safe" refers to whether an action leaves the
   state unchanged

   idempotent actions are guaranteed to have the same effect
   … each time they are invoked

   Synchronous actions signify that any state change is complete
   by the time the action's response is generated

   That isn't the case for async actions

   Actions further define the data schema for their input and
   output

   [Martin joins, and Michael summaries the discussion so far]

   Actions can be invoke functions or they can initiate processes

   Juanjo: the way to invoke an action should be the same for all
   actions whether or not they change the state etc., right?

   McCool: yes indeed

   The affordance in the TD tells you how to invoke the action

   McCool: synchronous actions may take appreciable time just so
   long as the state is stable when the response is sent

   <McCool> [15]w3c/wot-ngsi-ld#18

     [15] https://github.com/w3c/wot-ngsi-ld/issues/18


   Kaz: who is durkinza? Please type your name into IRC, thanks

   Zane: I am in the Web of Things activity

    PR 17

   McCool: my use case was about onboarding

   Martin's use case is how to describe an NGSI-LD entity as a
   thing

   <kaz> [16]PR 17 - Bauer Thing Description for NGSI-LD Entity as
   Thing Use Case

     [16] https://github.com/w3c/wot-ngsi-ld/pull/17


   He can use NGSI-LD to model digital twins

   McCool: WoT TD's can't describe all possible ways to use HTTP

   We can use feature requests to discuss any specific examples

   <kaz> [17]rendered MD

     [17] https://github.com/w3c/wot-ngsi-ld/blob/4d3fc1864e425a21c892d9306bf4aea423f4b12b/examples/EntityAsThing.md


   Martin: events should be easier for us to map

   Another example is where you have commanded a robot arm to
   move, and want to track its progress

   Martin: we need to look at some specific examples to see what
   problems arise

   At ETSI, we are still considering the use cases ...

   Kaz: we can look at some concrete examples to elucidate the
   requirements

    PR 14

   <kaz> [18]PR 14 - Define Onboarding Use Case example

     [18] https://github.com/w3c/wot-ngsi-ld/pull/14


   McCool: we need to talk about stakeholders at some point

   I want to merge the outstanding PRs, any objections [no]

    Stakeholders

   McCool: The WoT threat model categorises stakeholders
   … but not Digital Twin modellers

   Martin: We don't yet do that in our work

   McCool: whilst we hav a list of stakeholders in the WoT use
   cases, we don't yet provide definitions of what the terms
   signify

   <McCool> [19]w3c/wot-ngsi-ld#19

     [19] https://github.com/w3c/wot-ngsi-ld/issues/19


    Examples of mapping between NGSI-LD Entity and WoT Thing

   McCool: we can try to write a TD for a given NGSI-LD entity, I
   will create an issue to track that

   McCool asks for some candidate NGSI-LD entities for this
   exercise

   Martin: 2 or 3 examples, e.g. a concrete device and something
   more abstract

   McCool: we would then identify the gaps, i.e. things that can't
   be modelled in TDs
   … and capture feature requests for NGSI-LD as issues

   Our next call is in 2 weeks from now, and it would be good to
   have some examples in progress

   <kaz> [20]Issue 20 - Implement Test Case for "Entity as TD" Use
   case

     [20] https://github.com/w3c/wot-ngsi-ld/issues/20


   Some discussion on the existing use cases ...

   Juanjo: we need a use case involving collections of things

   Next meeting in 2 weeks

   <kaz> [adjourned]


    Minutes manually created (not a transcript), formatted by
    [21]scribe.perl version 244 (Thu Feb 27 01:23:09 2025 UTC).

     [21] https://w3c.github.io/scribe2/scribedoc.html

Received on Monday, 21 April 2025 13:57:25 UTC