Re: social-ISSUE-14 (elf-pavlik): as:Link adds a lot of complexity, if we keep it we need to clarify consequences of using it instead of as:Object [Activity Streams 2.0]

On 03/10/2015 11:25 AM, ☮ elf Pavlik ☮ wrote:
> On 02/23/2015 02:19 PM, Social Web Working Group Issue Tracker wrote:
>> social-ISSUE-14 (elf-pavlik): as:Link adds a lot of complexity, if we keep it we need to clarify consequences of using it instead of as:Object [Activity Streams 2.0]
>>
>> http://www.w3.org/Social/track/issues/14
>>
>> Raised by: Pavlik elf
>> On product: Activity Streams 2.0
>>
>> This continues discussion in two github issues
>> * as:Link from Linked Data perspective + comparing with hydra:Link - https://github.com/jasnell/w3c-socialwg-activitystreams/issues/24
>>
>> * clarify consequences of choice between as:Object and as:Link - https://github.com/jasnell/w3c-socialwg-activitystreams/issues/57
>>
>> Main issues I noticed so far:
>>
>> 1. AS2.0 Vocabulary uses Object | Link for domain and/or range in many properties
>> http://www.w3.org/TR/2015/WD-activitystreams-vocabulary-20150129/ (search for 'Object | Link' shows 43 such cases)
>>
>> 2. Currently some examples in latest published core spec use as:Link in JSON-LD while as:Object in RDFa (IMO it gives strong example of confusion it may cause, even author of the spec didn't use it in a consistent way!)
>> http://www.w3.org/TR/2015/WD-activitystreams-core-20150129/#example-2
>>
>> 3. as:Link breaks JSON-LD embedding
>> http://www.w3.org/TR/json-ld/#embedding
>> and may cause issue with JSON-LD framing
>> http://json-ld.org/spec/latest/json-ld-framing/ (work in progress)
>>
>> To stay honest, I don't see strong use cases requiring as:Link which would justify adding all this complexity and possibilities for confusion. Still if we decide to keep it, we should explain clearly when to use as:Link and when as:Object, elaborating on various consequences of making such choice.
> I suggested quick overview of this issue during today's telecon
> * https://www.w3.org/wiki/Socialwg/2015-03-10
> 
> As well as during our face 2 face
> * https://www.w3.org/wiki/Socialwg/2015-03-17
> 
> James, could you help with clarifying few aspects of as:Link
> 
> 
> 1. how does as:Link relate to httpRange-14?
> * http://en.wikipedia.org/wiki/HTTPRange-14
> * https://www.w3.org/wiki/HttpRange14Webography
> 
> Looking at examples in AS2.0 Core
> * http://www.w3.org/TR/activitystreams-core/#link
> 
> It looks like you mostly use it for media types of the image files as
> well as available width and height variants. I created an action for
> MediaObject to look at other ways to covering this functionality.
> * https://www.w3.org/Social/track/actions/42
> ACTION-42: MediaObject - gather options for its social syntax on a wiki page
Trying to ask simpler question, why in this example (from the spec) we
can't just use standard JSON-LD embeding and currently try to innovate
with construct like as:Link?

http://www.w3.org/TR/activitystreams-core/#ex3-jsonld

{
 ...
"actor": {
        ...
        "image": {
          "@type": "Link",
          "href": "http://example.org/martin/image",
          "mediaType": "image/jpeg",
          "width": 250,
          "height": 250
        }
      }
...
}
we have *blank node* here as subject of @type Link, and this link has
properties width: 250, height 250 etc (link itself, not the resource
identified by its href!)

if we want to give UI element - a link - size 250x250 maybe better to
put it in CSS? ;)


now standard JSON-LD embedding version

{
 ...
"actor": {
        ...
        "image": {
          "@type": "Image",
          "@id": "http://example.org/martin/image",
          "mediaType": "image/jpeg",
          "width": 250,
          "height": 250
        }
      }
...
}
here we have clear *subject* denoted by @id, which (this very Image, not
some link pointing at it) has properties width: 250, height: 250 etc.