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Re: ItemList

From: Dan Brickley <danbri@google.com>
Date: Tue, 10 Jun 2014 23:43:07 +0100
Message-ID: <CAK-qy=46h-SMpvjsFqXQ9NBKzVRtDRGH6GL_we3kp_f1_KuNFA@mail.gmail.com>
To: Markus Lanthaler <markus.lanthaler@gmx.net>
Cc: W3C Web Schemas Task Force <public-vocabs@w3.org>
On 10 June 2014 22:36, Markus Lanthaler <markus.lanthaler@gmx.net> wrote:
> On Tuesday, June 10, 2014 7:36 PM, Dan Brickley wrote:
>> On 10 June 2014 18:01, Alexander Shubin <ajax@yandex-team.ru> wrote:
>> >> Does it fit the schema design I posted?
>> >
>> > Sure. That’s why I proposed them :) Actually it uses the fact that ItemListElement is
>> Thing.
>> >
>> >> Re 'numberOfElements' maybe we can find an existing property to
>> >> extend?
>> >
>> > I couldn't find anything suitable.
> Very minor point but numberOfItems might be better given how the other properties and the type itself is documented:
> A list of *items* of any sort...
> A single list item...
> ListItem
> ...

Perhaps, but we also use the word element, i.e. itemListElement.

>> Adding,
>> +    <div typeof="rdf:Property" resource="http://schema.org/numberOfElements">
>> +      <span class="h" property="rdfs:label">numberOfElements</span>
>> +      <span property="rdfs:comment">The number of elements in an
>> ItemList.</span>
>> +      <span>Domain: <a property="http://schema.org/domainIncludes"
>> href="http://schema.org/ItemList">ItemList</a></span>
>> +      <span>Range: <a property="http://schema.org/rangeIncludes"
>> href="http://schema.org/Number">Number</a></span>
>> +    </div>
>> I've added one example so far, based on your first.
>> -> http://sdo-wip1.appspot.com/ItemList is updated, as is git
>> (https://github.com/danbri/schemaorg/commits/sdo-itemlist)

> Both JSON-LD examples are invalid:
> In the first example the value of itemListElement should be an object and thus be wrapped in {} and not [].

That's a very old example originally; it might be the JSON-LD
conversion was flawed, I'll check.

> The second example has two itemListElement properties which is invalid (strangely the same example is used at schema.org/ListItem!?). Both values should be wrapped in an array and collapsed into a single property.
> You could also use a JSON number to express the value of numberOfElements, i.e., remove the quotes around 315.

Thanks - I was grabbing time between meetings and only checked on
JSONLint! Lesson learned :)

I've gone with this for now (I'll check what we do elsewhere for numbers):

  "@context": "http://schema.org",
  "@type": "ItemList",
  "url": "http://multivarki.ru?filters%5Bprice%5D%5BLTE%5D=39600",
  "numberOfElements": "315",
  "itemListElement": [{
      "@type": "Product",
      "image": "http://img01.multivarki.ru.ru/c9/f1/a5fe6642-18d0-47ad-b038-6fca20f1c923.jpeg",
      "url": "http://multivarki.ru/brand_502/",
      "name": "Brand 502"
      "@type": "Product",
      "name": "..."
    "offers": {
      "@type": "Offer",
      "price": "4399 p."

Posted as http://sdo-wip1.appspot.com/ItemList

> It would also be nice if an example using next and previous would be added as people will probably struggle referencing it both from the ItemList and from a ListItem at the same time if there isn't an example they can copy-paste.

Yes, more example suggestions welcomed.

It's also an open question currently whether this design is adequate
to address Breadcrumb use cases (essentially an order list of url /
label pairs).

Received on Tuesday, 10 June 2014 22:43:38 UTC

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