Improvements to paginated TD retrieval spec

[farshidtz]

• Specify query arguments based on the original proposal
• Specify headers and modify to match https://www.w3.org/TR/ldp-paging/ as suggested in Handle huge set of Thing Descriptions (pagination, streaming, etc.) #16 (comment)
• Change spec document to match header-based approach

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Preview | Diff

[farshidtz]

@sebastiankb @mmccool Is there a way to set default values in TD?
The URI Template does not support it after draft v5 and I couldn't find anything in the TD's DataSchema either.

[mmccool]

Best to create an issue about this in the TD repo, otherwise it may not get addressed.

[sebastiankb]

sorry for my late response. TD allows to use terms which are not defined in data schema yet. Information can be found here https://w3c.github.io/wot-thing-description/#sec-data-schema-vocabulary-definition

[farshidtz]

Thanks. I'll reply on the new issue: w3c/wot-thing-description#1093

[AndreaCimminoArriaga]

I'm approving the review, as only remark I would add the optional functionality to return in the header the pair "Link" and an ontology class URI (as specified in the LDPP). In this way when the TDs are returned by using the headers one could know the types of these TDs.

[farshidtz]

We could try to fully comply with RFC7233 Range Requests. This would let us query range of bytes (or range of TDs) by setting equivalent request headers.

To have dedicated resource URLs for the RESTful API, we could allow passing range request values in query. E.g.:

/td?range-start=0&range-end=99&range-unit=TDs gives the first 100 TDs
/td?range-start=0&range-end=99&range-unit=bytes gives the first 100 bytes

The above is inline with LDP Paging. Moreover, we could borrow LDPP's Links spec to have next link and etag to identify the state.

[AndreaCimminoArriaga]

@farshidtz it makes sense to have both ranges, maybe we could even define others. I like the approach, it is sensible.

[danielpeintner]

I believe the range should be "10-11"
Otherwise it would be 3 more TDs and the count 12 does not match (0-11)

[farshidtz]

I changed this to draft. As mentioned in my last comment, we should try to fully comply with one standard and define query arguments to make pages addressable by URL. But this makes the specification even longer and this is overkill when there are much simpler approaches; see #145.

[mmccool]

Closing without merging, but as discussed Farshid will create a new PR with equivalent (but improved) content.