Re: ItemList examples

On Aug 4, 2014, at 11:25 PM, Adrian Giurca <giurca@tu-cottbus.de> wrote:

> itemPosition would not be the best solution as  JSON array is an ordered collection  and  JSON-LD is a flavour of JSON.  Add "unordered":"true" to catch order-irrelevant arrays.

In this case, the JSON-LD could define itemListElement to have a list container ("@container": "@list"), and that would explicitly provide an order to those elements. Similarly, @inlist could be used with RDFa. Microdata has no syntax for describing ordered values, although the Microdata Registry could define itemListElement to be ordered (or an alias of this property). Unfortunately, I don't believe that such ordering is honored in the schema.org model, but I think that would be worth exploring.

Another thing absent from this proposal is some way of dealing with external enumerations. It might be useful to consider a use case where the value of a property was a URL identifying such an external list. For example, looking at the Sports Event Series, which could potentially be quite large:

{
  "@context": "http://schema.org",
  "@type": "SportsEvent",
  "@id": "/world-series/2013",
  "name": "2013 World Series",
  "subEvent": {
    "@id": "/world-seriece/2013/subEvents",
    "@type"; "ItemList"
  }
}

Then the list could be found through indirection:

{
  "@context": "http://schema.org",
  "@type": "ItemList",
  "@id": "/world-series/2013/subEvents",
  "itemListElement": [{
    "@type": "ListItem",
    "itemPosition": "1",
    "item": {
      "@type": "SportsEvent",
      "@id": "http://mlb.com/ws2013gl",
      "name": "2013 World Series - Game One"
    }, {
      ...
    }]
}

It might be even more useful if the individual items used the same property as refers to the list, rather than "item"; this would make the rules more like the Role class, where the property referring to the Role is also used within the Role.

Lastly, very large lists might need to be paginated, but that could be left for some follow-on proposal.

Gregg

> All the best,
> -Adrian
> On 8/4/2014 6:10 PM, Dan Brickley wrote:
>> Just a quick note to share an in-progress document towards improving
>> the ItemList type. Many thanks to Vicki and Jason for taking a lead on
>> this.
>> 
>> https://docs.google.com/a/google.com/document/d/1WIQvnaAWCdcPn3AouznLELbLCcHqkGlttYREChVFycc/edit#
>> 
>> For now it's shared a public google doc. We can export HTML later, but
>> if anyone has trouble with it in this form please let me know.
>> 
>> The idea is to collect together and review various ItemList-related
>> scenarios across schema.org, to get an overview for possible
>> improvements to ItemList. There are also machine readable schemas in a
>> github branch (https://github.com/danbri/schemaorg/tree/sdo-itemlist/data)
>> that correspond to recent proposals discussed here.
>> 
>> cheers,
>> 
>> Dan
>> 
> 
>

Received on Tuesday, 5 August 2014 17:18:42 UTC