Re: JSON-LD and context questions (plus no additionalType and I don't like DataRecord)

Hi Melanie,

I think you want to do this.

{
   "@context": [ "http://schema.org",
               {
                 "OBI" :"http://purl.obolibrary.org/obo/OBI_"
               }
   ],
   "@type": "DataRecord",
   "@id": "biosample:SAMEA100000",
   "mainEntity": {
     "@type" : "OBI:0000747"
   }
}

Here we start with merging two contexts. The standard schema.org and one 
just for your file. Here trying to make the OBI one easier to read.

So your top level is a DataRecord linked via schema:mainEntity to 
something with type "OBI:0000747".

You can see what a JSON-LD snipit means in RDF at 
https://json-ld.org/playground/ e.g. http://tinyurl.com/y9ccen2j


I am repeating myself here but in additionalType is only for the 
MicroData serialization which no one in the bioschema space seems to use.

If you have more than one type just do

{
   "@context": [ "http://schema.org",
               {
                 "OBI" :"http://purl.obolibrary.org/obo/OBI_"
               }
   ],
   "@type": [ "DataRecord", "Thing", "WebPage" ],
   "@id": "biosample:SAMEA100000",
   "mainEntity": {
     "@type" : "OBI:0000747"
   }
}

To be honest I don't like the DataRecord at all and am still advocating 
it's removal from bioschema. Mostly because schema.org doesn't have 
StoreRecord, just Store.

Regards,
Jerven

PS Alasdair, Leyla maybe remove additionalType considering the confusion 
it has generated and we have no Microdata examples.

On 11/21/2018 02:40 PM, Melanie Courtot wrote:
> Hi,
> 
> Hi - following up discussions at the BioHackathon we’re looking at 
> updating our sample serialisation. We are running into some questions 
> with respect to the context usage and are hoping someone can help.
> 
> Specifically, I’m trying to understand the usage of contexts and base 
> IRIS - I’m familiar with XML base and namespaces as well as RDF, but I 
> was looking at some schema.org <http://schema.org> JSON-LD and trying to 
> understand nuances based on the official spec at 
> https://www.w3.org/TR/json-ld/#the-context
> 
> Here is the relevant excerpt from our serialisation:
> 
> {
>    "@context": "http://schema.org",
>    "@type": "DataRecord",
>    "identifier": "biosample:SAMEA100000",
>    "mainEntity": {
>      "@context": [
>        "http://schema.org",
>        {
>          "@base": "http://schema.org"
>        },
>        {
>          "Sample": {
>            "@id": "http://purl.obolibrary.org/obo/OBI_0000747"
>          }
>        }
>      ],
> ….
> 
> 
> As you can see there is a repetition of contexts and base that I don’t 
> think is needed.
> 
> 1. The first context, which is at the top level in our sample page, 
> seems to match example 4 from the spec, and would actually be a 
> reference to another json-ld context? Though it doesn’t point to a 
> json-ld file. I couldn’t find this specific notation anywhere else in 
> the JSON-LD spec, but this is what is used throughout on schema.org 
> <http://schema.org>, eg https://schema.org/Person, example 1 in json-ld.
> 
> 2. The whole page is a DataRecord (where DataRecord is a new type we are 
> proposing to schema.org <http://schema.org>, so should expand to 
> http://schema.org/DataRecord) - which is expected as we want to describe 
> a data record in our resource, and we then describe the mainEntity in 
> that DataRecord.
> As you can see, the context is redefined in mainEntity - my 
> understanding is that this means this specific context declaration will 
> be valid only within the scope of that mainEntity. This context reads
> 
>      "@context": [
>        "http://schema.org",
>        {
>          "@base": "http://schema.org"
>        },
> 
> I don’t understand what the first "http://schema.org” means, and whether 
> it’s needed as we explicitly define the base. Also this seems redundant 
> with the global page context we have defined at the page level, so I’d 
> be tempted to just have
> 
>      "@context": {
>          "@base": "http://schema.org"
>        },
> 
> At the top level.
> 
> 3. Finally, we are trying to say that http://schema.org/Sample (which is 
> a new type we’re proposing) also has the IRI 
> "http://purl.obolibrary.org/obo/OBI_0000747”. I’m not sure adding
> 
>        {
>          "Sample": {
>            "@id": "http://purl.obolibrary.org/obo/OBI_0000747"
>          }
> 
> In the context is the right way of doing it, or whether we should just 
> add an additionalType <https://schema.org/additionalType> property on 
> the sample object later on - or should we do both?
> 
> Apologies for the rather long email, but I hope we have a JSON-LD 
> specialist on this list that can provide some guidance as to how we 
> should best use those. Thanks in advance for any help!
> 
> Cheers,
> Melanie
> 
> 
> 
> 
> -- 
> Mélanie Courtot, PhD
> GA4GH/BioSamples Project lead
> European Bioinformatics Institute (EMBL-EBI)
>

Received on Wednesday, 21 November 2018 14:01:28 UTC