Write Croissant metadata

Writes a Croissant object as a JSON-LD document with the standard context of its version (see croissant_context()). conformsTo always includes the Croissant IRI of x@version.

Usage

write_croissant(x, path = NULL, pretty = TRUE)

Arguments

x

Croissant object.

path

Optional Character: File to write. If NULL, the JSON text is returned.

pretty

Logical: Whether to indent the JSON.

Value

If path is NULL, the JSON text as a character scalar of class json; otherwise path, invisibly.

Details

In version 1.1, a name or description named by language tag is written as a language map. In version 1.0, it is written as an array of @value/@language objects.

Author

EDG

Examples

x <- Croissant(
  name = "Titanic",
  distribution = list(
    FileObject(id = "passengers.csv", content_url = "titanic.csv", encoding_format = "text/csv")
  )
)
cat(write_croissant(x))

#> {
#>   "@context": {
#>     "@language": "en",
#>     "@vocab": "https://schema.org/",
#>     "annotation": "cr:annotation",
#>     "arrayShape": "cr:arrayShape",
#>     "citeAs": "cr:citeAs",
#>     "column": "cr:column",
#>     "conformsTo": "dct:conformsTo",
#>     "containedIn": "cr:containedIn",
#>     "cr": "http://mlcommons.org/croissant/",
#>     "data": {
#>       "@id": "cr:data",
#>       "@type": "@json"
#>     },
#>     "dataBiases": "cr:dataBiases",
#>     "dataCollection": "cr:dataCollection",
#>     "dataType": {
#>       "@id": "cr:dataType",
#>       "@type": "@vocab"
#>     },
#>     "dct": "http://purl.org/dc/terms/",
#>     "description": {
#>       "@container": "@language"
#>     },
#>     "equivalentProperty": "cr:equivalentProperty",
#>     "examples": {
#>       "@id": "cr:examples",
#>       "@type": "@json"
#>     },
#>     "extract": "cr:extract",
#>     "field": "cr:field",
#>     "fileObject": "cr:fileObject",
#>     "fileProperty": "cr:fileProperty",
#>     "fileSet": "cr:fileSet",
#>     "format": "cr:format",
#>     "includes": "cr:includes",
#>     "isArray": "cr:isArray",
#>     "isLiveDataset": "cr:isLiveDataset",
#>     "jsonPath": "cr:jsonPath",
#>     "key": "cr:key",
#>     "md5": "cr:md5",
#>     "name": {
#>       "@container": "@language"
#>     },
#>     "parentField": "cr:parentField",
#>     "path": "cr:path",
#>     "personalSensitiveInformation": "cr:personalSensitiveInformation",
#>     "prov": "http://www.w3.org/ns/prov#",
#>     "rai": "http://mlcommons.org/croissant/RAI/",
#>     "readLines": "cr:readLines",
#>     "recordSet": "cr:recordSet",
#>     "references": "cr:references",
#>     "regex": "cr:regex",
#>     "repeated": "cr:repeated",
#>     "replace": "cr:replace",
#>     "samplingRate": "cr:samplingRate",
#>     "sc": "https://schema.org/",
#>     "sdVersion": "cr:sdVersion",
#>     "separator": "cr:separator",
#>     "source": "cr:source",
#>     "subField": "cr:subField",
#>     "transform": "cr:transform",
#>     "unArchive": "cr:unArchive",
#>     "value": "cr:value",
#>     "wd": "https://www.wikidata.org/wiki/"
#>   },
#>   "@type": "sc:Dataset",
#>   "name": "Titanic",
#>   "conformsTo": "http://mlcommons.org/croissant/1.1",
#>   "distribution": [
#>     {
#>       "@type": "cr:FileObject",
#>       "@id": "passengers.csv",
#>       "contentUrl": "titanic.csv",
#>       "encodingFormat": "text/csv"
#>     }
#>   ]
#> }

path <- tempfile(fileext = ".json")
write_croissant(x, path)
read_croissant(path)

#> <Croissant>
#>   name: Titanic
#>   version: Croissant 1.1
#>   distribution: 1 FileObject
#>   record sets: 0
#>