Efficient Interchange of CSS

Thing Description (TD) Serialization

F2F Düsseldorf - July 2017

Daniel Peintner

Goals

Identify suitable serialization formats for WoT Thing Description

propose two default variants (text-based vs. binary-based)
should be able to represent the TD core model
extendable by allowing to integrate vocabularies from other contexts

What is not a goal?

We MUST NOT invent any new format

What is important for WoT TD format

Adaption in (other) communities/platforms
Acceptance (web developer vs. embedded developer)
Data exchange size
Processing speed/requirements
Royalty Free
Free/open source implementations?

Possible Candidates

Text-based

JSON-LD
JSON
RDFa/XML
???

Binary-based

EXI4JSON
CBOR
Smile
???

Text-based - Current JSON-LD Example

{
  "@context": ["http://w3c.github.io/wot/w3c-wot-td-context.jsonld"],
  "@type": ["Thing"],
  "name": "MyTemperatureThing",
  "interaction": [{
      "@type": ["Property"],
      "name": "temperature",
      "outputData": { "type": "number" },
      "writable": false,
      "link": [{
        "href" : "coap://mytemp.example.com:5683/temp",
        "mediaType": "application/json"
        }]
  }]
}

Text-based - What is next
_{Compare acceptance of JSON-LD vs. JSON vs. RDF vs ???}

Complexity
Verbosity
Conversion to other models (Turtle, ...)

How to come to a conclusion?

TD Serialization test-bed

The test-bed can be found on github
(see github.com/w3c/wot-thing-description/tree/master/test-bed)
Started to collect data from various sources
- WoT Current Practices document
- PlugFests
- SDO mappings

Measurements _{Osaka PlugFest}

Measurements _{Düsseldorf PlugFest}

Outlook
_{How can we improve even further}

CBOR

TODO Carsten

EXI4JSON

Share knowledge between encoder & decoder
Use structural knowledge

Optimized JSON-LD Example

{
  "@context": ["http://w3c.github.io/wot/w3c-wot-td-context.jsonld"],
  "@type": ["Thing"],
  "name": "MyTemperatureThing",
  "interaction": [{
      "@type": ["Property"],
      "name": "temperature",
      "outputData": { "type": "number" },
      "writable": false,
      "link": [{
        "href": "coap://mytemp.example.com:5683/temp",
        "mediaType": "application/json"
        }]
  }]
}

Thing Description (TD) Serialization

Thing Description (TD) Serialization

Table of Contents

Goals

What is important for WoT TD format

Possible Candidates

Text-based - Current JSON-LD Example

Text-based - What is next
_{Compare acceptance of JSON-LD vs. JSON vs. RDF vs ???}

How to come to a conclusion?

TD Serialization test-bed

Measurements _{Osaka PlugFest}

Measurements _{Düsseldorf PlugFest}

Outlook
_{How can we improve even further}

Optimized JSON-LD Example

Measurements _PlugFests

Any Questions?

Thanks for your attention!

Thing Description (TD) Serialization

Table of Contents

Goals

What is important for WoT TD format

Possible Candidates

Text-based - Current JSON-LD Example

Text-based - What is next Compare acceptance of JSON-LD vs. JSON vs. RDF vs ???

How to come to a conclusion?

TD Serialization test-bed

Measurements Osaka PlugFest

Measurements Düsseldorf PlugFest

Outlook How can we improve even further

Optimized JSON-LD Example

Measurements PlugFests

Any Questions?

Thanks for your attention!

Text-based - What is next
_{Compare acceptance of JSON-LD vs. JSON vs. RDF vs ???}

Measurements _{Osaka PlugFest}

Measurements _{Düsseldorf PlugFest}

Outlook
_{How can we improve even further}

Measurements _PlugFests