<inserted> Harold's slides: https://lists.w3.org/Archives/Public/www-archive/2020Jan/att-0002/JSONLD11_early_draft_.pdf
(Harold presents slides)
(slide 2)
(slide 3)
(slide 4)
harold: Typically when you learn about JSON-LD, you start learning about the @context to turn JSON into JSON-LD, but today we're approaching it differently.
(slide 5)
harold: If I have JSON, what do I do to get RDF? Or how do I get from RDF to JSON? Then in part 2 (not today) we'll start adding the @context.
(slide 7)
harold: JSON-LD Playground is a wonderful tool. It's a reference implementation of JSON-LD 1.1.
(slide 8)
harold: First, how do we map the subject into RDF? In JSON the subject is not named, it is just indicated by curly braces. the properties are predicates.
(slide 11)
harold: First, we need to convert JSON property names to URIs.
(slide 13)
harold: For the moment, I am just
assiging temporary URIs.
... The result is valid JSON-LD!
(slide 14)
harold: If I plug it into the
JSON-LD Playground, I can see the resulting RDF triples.
... Another way to do this, in the Playground, if you had an
@context, you could give a default URI prefix, such as the one
for FHIR.
... You can see the RDF in the NQuads tab of the
playground.
(slide 15)
harold: Also notice that JSON-LD
maps some native types from JSON to RDF, such as boolean
true.
... Also notice that by default it does not preserve JSON list
order.
(slide 18)
harold: Next, we need to add
subject URIs. We do this with @id.
... We can put them on any nodes we want.
(slide 20)
(slide 21)
harold: Next, we need to indicate
data types.
... But at this point we need to add another triple for @type
and @value.
(slide 23)
harold: There are 3 equivalent
ways to indicate the same thing in JSON-LD.
... in Expanded format it gets rid of the @context.
... Not very useful for JSON traversal.
... The Compacted format is as terse as possible, but also
still has no @context.
(slide 24)
s/Jssjad/Sajjad/
(slide 42)
harold: RDF needs URIs for datatypes. You can also add a language tag.
(slide 43)
(slide 44)
harold: You can also embed JSON as RDF literals.
(slide 24)
harold: Everything we can say in
JSON, we can turn it into RDF.
... But there are things you can can in RDF that you cannot say
in JSON.
(slide 26)
harold: What ive I have two
unrelated subject? You can wrap the JSON inside an
@graph.
... But you need to put them inside a JSON list "[...]" for the
syntax to be allowed.
(slide 46)
harold: In JSON, lists are
ordered. But in JSON-LD by default they are unordered.
... There are decorators that you can add. @set gives you the
default -- a set. @list gives you an RDF list, which is not
very useful in RDF because RDF lists are not
SPARQL-friendly.
... The JSON-LD community considered a different list
representation for RDF, but there was not RDF community
consensus on which alternate list mechanism to use, so JSON-LD
did not add anything.
... Right now, to create a usable ordered list, you need to
edit the JSON. For this reason, we will have to pre-process to
add an explicit list index.
(slide 62)
harold: One change we still have to make to the FHIR/JSON is to add a list index variable.
(slide 35)
(slide 36)
harold: Framing is interesting.
JSON is a tree. But what if we have a non-tree RDF structure
that we want?
... I have barely touched on the @context, because we first
need to address all of the issues of getting into RDF, and then
we can add the @context to help do it.
David: suggestions?
___: Customize examples to FHIR.
ADJOURNED
This is scribe.perl Revision: 1.154 of Date: 2018/09/25 16:35:56 Check for newer version at http://dev.w3.org/cvsweb/~checkout~/2002/scribe/ Guessing input format: Irssi_ISO8601_Log_Text_Format (score 1.00) FAILED: s/Jssjad/Sajjad/ Succeeded: i|Harold presents slides|Harold's slides: https://lists.w3.org/Archives/Public/www-archive/2020Jan/att-0002/JSONLD11_early_draft_.pdf Present: Harold_Solbrig David_Booth EricP Quoqian_Jiang Andrea_Volxz Bill_Duncan Daniel_Stone Davera_Gabriel Dazhi_Jiao fragosog Gaurav_Vaidya Haendel Julie_McMurry Lauren_Chan Matthew_Brush maura Melissa_Cook Milen_Nikolov Peter_Robinson RIchard_Z Jsjjad Anne_Thessen Tom Tricia No ScribeNick specified. Guessing ScribeNick: dbooth_ Inferring Scribes: dbooth_ WARNING: No date found! Assuming today. (Hint: Specify the W3C IRC log URL, and the date will be determined from that.) Or specify the date like this: <dbooth> Date: 12 Sep 2002 People with action items: WARNING: IRC log location not specified! (You can ignore this warning if you do not want the generated minutes to contain a link to the original IRC log.)[End of scribe.perl diagnostic output]