W3C

– DRAFT –
WoT-WG - TD-TF

15 March 2023

Attendees

Present
Cristiano_Aguzzi, Daniel_Peintner, Ege_Korkan, Jan_Romann, Kaz_Ashimura, Luca_Barbato, Michael_McCool, Sebastian_Kaebisch, Tomoaki_Mizushima
Regrets
Koster
Chair
Sebastian/Ege
Scribe
kaz, luca_barbato

Meeting minutes

Minutes

<kaz> Mar-8

Sebastian: would ask you all to think about joining the TF leader
… we need at least two leaders

Ege: check consensus for the past minutes
… minutes approved.

Task Force leader clarification

<kaz> I'd like to provide some clarification on the procedure first. TF leader is not part of the Charter discussion. Also TF leader is not appointed by the WG Chair./

Kaz: I'd like to provide some clarification on the procedure first. TF leader is not part of the Charter discussion. Also TF leader is not appointed by the WG Chair.
… Choosing TF leader(s) is to be discussed by the TF itself like we chose Cristiano as an additional TF leader for Scripting API. We can simply report back to the main group later. If needed, we can have 3 moderators, Ege, Sebastian, Koster

<dape> s/Ege, Sebastian, Koster

sebastian: The moderator requirements are to prepare the meeting and moderate them

Cristiano: Wouldn't be better to to nominate separate responsible for sections of the TD?
… e.g. 2 responsibles for the binding templates, 1 for profile, ...

Luca: We could have a list of topic first and then find moderators
… and possibly have rotation on moderation if the workload is large enough to warrant it

Kaz: we could discuss further when Koster is present
… note that from my viewpoint, it would not be fair to have two moderators from one specific company.

Charter-related topics

<kaz> Remaining issues

Ege: We do not have much left to say to discuss since most discussed already
… remaning items to discuss

PR 88

<Ege> PR 88 - Revised scope section, reordered, clarified language

Kaz: clarification on what's about the PR

Ege: The change is just 1 line in the Charter document

PR 78

<Ege> PR 78 - Define Streaming and RTSP work items in Details

<cris_> +1

Ege: The PR is about multimedia streaming, interested parties should comment on the PR

Issue 59

<kaz> Issue 59 - Add composed Things work items

Cristiano: What do we want to do, what are we missing?

one case we want to act upon the aggregate
… ... one case we want to just signal the relationship

<kaz> ek: (shows Example 30 from the TD spec Editor's Draft)

<kaz> Example 30 from TD

Luca: I'd like more clarification on this topic

Ege: We should see we have consensus on explore more on the next charter

Kaz: As already mentioned during the Charter call, this is not Charter issue but detailed work item for the next version of TD, so we should move this issue to the wot-thing-description repository

Cristiano: +1

<dape> DP: allowing "group" interactions based on composed things sounds too much to me. Suppose an electric vehicle has several motors and a stop() interactions which then would need to be forwarded to "linked" motors. I don't think the TD should do that. A tool might do that though

TD Testing

At-risk features

Ege: many at-risk items in the TD are security assertions
… we should have the discussion in the next security call

<Ege> https://github.com/w3c/wot-testing/blob/main/events/2023.03.DevMtg/TD/atrisk-explanations.md

<kaz> items above

Ege: Also we should fill out the document with our at risk items above

<kaz> i/may at/subtopic: At-risk features/

Ege: The deadline is 27th March
… implementors are invited to participate
… we will review the document next week

Binding Templates

Issue 255

<Ege> w3c/wot-binding-templates#255 Issue 255 - A diagram to help understand what is happening in operation mappings.

Ege: The patch has the diagram
… it explains the specific items of the Form
… and how the requests flow looks like

<cris_> +1 sebastian's comment

sebastian: looking forward to see the diagram

Luca: png vs svg as medium in the document

<kaz> related PR 262 - Explain core binding mechanism

<Zakim> dape, you wanted to quotes in TD snippet

<Ege> diagram preview

Ege: Shall we put the quotes in the snippet?

Cristiano: It is not a valid json to begin with, not strong preference

sebastian: Would be nice to have more diagrams like this one

Ege: We can make a requirement to add sequence diagrams in the protocol bindings
… we have some in the HTTP protocol binding
… we can make sure to get the detail level not too deep

Kaz: The TD snippet should be valid, we should add the quotes as needed
… the diagram should have a paragraph describing the use case scenario related to that

sebastian: I would leave it as-is

Kaz: I prefer the snippet being valid even if it is a fragment

Luca: +1

<kaz> ek: ok. will fix it

Issue 252

<kaz> Issue 252 - Mention that a binding is mandatory for a TD to exist

<Ege> related PR 261 - Update ReSpec in ontology template

Ege: Fix ReSpec warnings

Ege: Ok to merge?
… merged

(no objections)

merged

PR 260

<Ege> PR 260 - Use dct:creator instead of dct:author in ontologies

Ege: any objections to merge?

(none)

merged

PR 263

<Ege> PR 263 - Specifying terms influenced by different bindings

Ege: (shows the preview)
… (describes the text and table under Example 5)

Example 5

Ege: this is still a draft, and would like to hear people's opinions

Luca: how are we going to specify which is correct href value?

Ege: if you see Modbus...

Modbus URL ABNF Syntax

bf: that seems to be risky...
… how to validate it?
… it could be a starting point, but we need further improvement
… we have to figure out what socket to be used in this context

Ege: ideally the Consumer should pick one for their implementation
… if the choice was wrong, the configuration would be gone

Luca: would be better to specify the expectation

Ege: do you think asking the implementers to follow the ABNF notation is too much?

Luca: it would be risky
… asking this in the Ontology would make sense

Cristiano: agree
… don't see any Consumer implementations yet
… would be easier to follow the URL
… the other point around registry

Daniel: maybe you can show the table again...
… paragraph above the table says "keywords" and "terms"
… also "Assignment" within the table seems to be odd

Ege: copied from the TD spec...

Daniel: not sure about what term would be better, though

Kaz: we should collect developer experience for binding with Modbus, etc.
… maybe a good topic for the possible Dev Meetup on Binding

Ege: ok
… would like to create an issue to remember this

issue 264 - Get binding usage information from communities

Ege's comments on PR 263 based on the discussion

Ege: (then goes through section 4.3)

preview - 4.3 Platform Binding Templates

Kaz: just to make sure, is there any clarification about the difference between "Protocol Binding" and "Platform Binding"?

Ege: yes, some text within the Introduction section

Kaz: ok
… remember we agreed on that text the other day
… but maybe it would be better to have that clarification text withing section 4 "Binding Template Mechanisms" itself?

Ege: right. can understand your point
… (creates another issue about that; to be done later)

PR 259

<Ege> PR 259 - Rename CoAP blockwise parameters

Jan: some discussion about the position

related issue 256 - Rename cov:block2SZX to cov:block2Size

Jan: we could make this PR itself, and then I can add further improvement

(this is updates for coap/coap.schema.json and coap/index.html)

merged

Jan: will work on related PR 246

Kaz: we won't talk about PR 246 itself today. right?

Ege: right

Issue 232 - Next WD Path

Issue 232 - Next WD Path

Ege: our deadline is Mar 30
… would like to have more opinions around naming

Issue 243

Issue 243 - Changing the Payload Bindings to Content Type Bindings

McCool: "Payload Bindings" would be clearer, I think
… "Payload" is more specific term than "Content Type"

Cristiano: could you elaborate the background a bit more, Ege?

Sebastian: would agree with McCool
… "Content Type" sounds more generic to me
… "Payload" is to be exchanged for interaction

Ege: ok
… we should see what different platforms do

Sebastian: we should clarify what is expected here

Ege: should go for platform discussion
… if the data schema with HUE or OCF goes in platforms, this change would make sense

Sebastian: right

Luca: should be able to look up the binding
… we have to make sure our expectation

Ege: Consumers would need to pick

Kaz: would agree with Luca's viewpoint
… we should clarify our expectation for binding first at the top of section 4
… protocol part and content part to be handle how
… then we should be able to choose which term would be the best, content or payload (or something else)

Luca: how to look up the content type and validate it?

Cristiano: wanted to comment on the issue
… more aligned with what we started with
… we're now talking about how to serialize the information
… actual contentType content

Ege: would prefer making decision prior to the next publication
… McCool, do you still prefer "Payload Binding"?

McCool: if you all think "Content Type Binding", that's OK

Kaz: is what we want really binding of "ContenType"?
… it implies "MIME Type" to people
… so if what we want is rather binding of the content as a whole, maybe it would be better to say "Content Binding" as Daniel mentioned

McCool: right

Luca: do we have examples on this kind of Binding (ContentType Binding/Payload Binding)?

Ege: yeah
… (shows the examples at Appendix B)

Appendix B. Examples of Payloads and Data Schemas from IoT Platforms and Standards

Ege: this is an example of SenML Payload

<sebastian> I have to go

<sebastian> bye

Luca: what if a payload using CBOR is transferred?

Ege: (shows example 6)

Example 6 - JSON and CBOR media types in forms

Luca: what is the data schema for that?

Kaz: sorry but we're out of time
… so would suggest we continue the discussion next week

<Ege> w3c/wot-binding-templates#226

Ege: ok
… note that there is a related issue 226 on "Platform Binding" as well

[adjourned]

Minutes manually created (not a transcript), formatted by scribe.perl version 210 (Wed Jan 11 19:21:32 2023 UTC).