Pure JSON

vita <- readr::read_file("../../static/js/vita.json")

jq(vita, '."@reverse".author[]  | 
   { year: .dateCreated, 
     author: .author[] | [.givenName, .familyName]  | join(" ")
   }') %>% combine() %>% fromJSON()

frame <-
'{
"@context": "http://schema.org",
"@type": "ScholarlyArticle",
"author": {
  "@type": "Person",
  "givenName": {},
  "familyName": {},
  "@explicit": true
},
"dateCreated": {},
"@explicit": true
}'


vita <- jsonld::jsonld_frame("../../static/js/vita.json", frame)

as.character(vita) %>% 
  jq('."@graph"[] | { 
     year: .dateCreated, 
     author: .author[] | [.givenName, .familyName] | join(" ")    
     }') %>% combine() %>% fromJSON()

Switching contexts and framing

context <- 
 '{
    "prism": "http://prismstandard.org/namespaces/basic/2.1/",
    "dc": "http://purl.org/dc/terms/",
    "bibo": "http://purl.org/ontology/bibo/",
    "foaf": "http://xmlns.com/foaf/0.1/",
    "owl": "http://www.w3.org/2002/07/owl#",
    "schema": "http://schema.org/",

    "schema:pageStart": "prism:startingPage", 
    "schema:pageEnd": "prism:endingPage",
    "schema:volumeNumber": "prism:volume",
    "schema:identifier": {"@id": "prism:issn", "@type": "@id"},

    "schema:Periodical": "bibo:Journal",

    "schema:author": "dc:creator",
    "schema:isPartOf": "dc:isPartOf",
    "schema:publisher": "dc:publisher",
    "schema:name": "dc:title",

    "schema:familyName": "foaf:familyName",
    "schema:givenName": "foaf:givenName",
    "schema:Person": "foaf:Person",

    "schema:sameAs": {"@id": "owl:sameAs", "@type": "@id"},
    "schema:Date": "xsd:date",
    "schema:datePublished": {"@id": "http://purl.org/dc/terms/date", "@type": "schema:Date"}
}'

Compact raw JSON into this context

jsonld_compact("ex.json", context) %>% 
  fromJSON(simplifyVector = FALSE) -> X

Now replace that context with schema.org context, a bit of a hack

X[["@context"]] <- "http://schema.org"
X %>% 
  toJSON(auto_unbox = TRUE, pretty = TRUE) %>% 
  jsonld_compact("http://schema.org") -> Y

Now frame our desired results to explicitly include only the elements we request, giving the graph in the desired tree structure:

frame <- 
'{"@context": "http://schema.org",
 "@graph": {
   "id": {},
   "name": {},
   "pageStart": {},
    "pageEnd": {},
    "isPartOf": {
      "name": {},
      "identifier": {},
      "@explicit": true
    },
    "author": [
            {
              "givenName": {},
              "familyName": {},
              "@explicit": true
            }],
   "@explicit": true
 }
}'

jsonld_frame(Y, frame)

## {
##   "@context": "http://schema.org",
##   "@graph": [
##     {
##       "id": "http://dx.doi.org/10.1002/ece3.2314",
##       "author": [
##         {
##           "id": "http://id.crossref.org/contributor/carl-boettiger-2etprmps2zm1a",
##           "type": "Person",
##           "familyName": "Boettiger",
##           "givenName": "Carl"
##         },
##         {
##           "id": "http://id.crossref.org/contributor/t-alex-perkins-2etprmps2zm1a",
##           "type": "Person",
##           "familyName": "Perkins",
##           "givenName": "T. Alex"
##         },
##         {
##           "id": "http://id.crossref.org/contributor/benjamin-l-phillips-2etprmps2zm1a",
##           "type": "Person",
##           "familyName": "Phillips",
##           "givenName": "Benjamin L."
##         }
##       ],
##       "isPartOf": null,
##       "name": "After the games are over: life-history trade-offs drive dispersal attenuation following range expansion",
##       "pageEnd": "6434",
##       "pageStart": "6425"
##     }
##   ]
## }

Note that the RDF has different semantic models than schema.org: for instance, volume is a property of the scholarly article (well, it’s untyped in the RDF, but it’s a property of the object described by the article DOI), while in schema.org, volumeNumber is a property of a Periodical (or PublicationVolume), which hasParts made up of PublicationIssue objects, themselves hasParts made up of ScholarlyArticles. The whole purpose of JSON-LD functions are to respect semantics, therefore there is no way we can use JSON-LD operations to alter these semantics.

As long as we aren’t changing the object structures though, we can change the vocabulary. This is really also something of a hack: we compact the original data, and then just chop off the @context and provide our own @context that gives schema.org definitions to the terms.

JSON-LD is commonly used to change key names, but this assumes that both contexts can be defined relative to the same URIs. e.g. we can say that in the context of Dublin Core, implicitly "title": "http://schema.org/name", or explicitly:“https://purl.org/dc/title”: “http://schema.org/name”`.

Perhaps this ought instead to be done with an ontological operation and the assertion of sameAs and similar relationships. Perhaps that would also permit moving between these different levels?

Note that items with specific types must be declared as such to match types expected in schema.org. Others can be captured as schema.org terms just by setting the default @vocab.