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The JavaScript Object Notation is specified by ECMA. The syntax defines three types of elements:

  • objects, a set of key-value pairs, where keys are supposed to be unique;
  • values, which are either strings, numbers, boolean, or the primitive 'null';
  • and, arrays, which specify sequences (containing other arrays, objects, or values).

According to Facade-X model, SPARQL Anything interprets objects and arrays as containers:

  • RDF properties are used to link objects to values.
  • Arrays are represented by the ordered sequence component.
  • Values are expressed as rdf:Literal, selecting relevant XSD datatypes from the RDFS specification: xsd:string, xsd:boolean, xsd:int, xsd:float

Currently, fields with the 'null' value are ignored. <!-- However, we may decide to represent it as blank node or to create a primitive entity to express it, for example, similar to \tt{rdf:nil}.}. -->

Extensions

SPARQL Anything selects this transformer for the following file extensions:

  • json

Media types

SPARQL Anything selects this transformer for the following media types:

  • application/json
  • application/problem+json

Default implementation

Default Transformation

Data

{
    "stringArg": "stringValue",
    "intArg": 1,
    "booleanArg": true,
    "nullArg": null,
    "arr": [ 0, 1 ]
}

Located at https://sparql-anything.cc/examples/simple.json

Query

CONSTRUCT 
  { 
    ?s ?p ?o .
  }
WHERE
  { SERVICE <x-sparql-anything:location=https://sparql-anything.cc/examples/simple.json>
      { GRAPH ?g
          { ?s  ?p  ?o }
      }
  }

Facade-X RDF

PREFIX dc:     <http://purl.org/dc/elements/1.1/>
PREFIX eg:     <http://www.example.org/>
PREFIX fx:     <http://sparql.xyz/facade-x/ns/>
PREFIX ja:     <http://jena.hpl.hp.com/2005/11/Assembler#>
PREFIX owl:    <http://www.w3.org/2002/07/owl#>
PREFIX rdf:    <http://www.w3.org/1999/02/22-rdf-syntax-ns#>
PREFIX rdfs:   <http://www.w3.org/2000/01/rdf-schema#>
PREFIX rss:    <http://purl.org/rss/1.0/>
PREFIX vcard:  <http://www.w3.org/2001/vcard-rdf/3.0#>
PREFIX whatwg: <https://html.spec.whatwg.org/#>
PREFIX xhtml:  <http://www.w3.org/1999/xhtml#>
PREFIX xsd:    <http://www.w3.org/2001/XMLSchema#>
PREFIX xyz:    <http://sparql.xyz/facade-x/data/>

[ rdf:type        fx:root;
  xyz:arr         [ rdf:_1  "0"^^xsd:int;
                    rdf:_2  "1"^^xsd:int
                  ];
  xyz:booleanArg  true;
  xyz:intArg      "1"^^xsd:int;
  xyz:stringArg   "stringValue"
] .

Options

Summary

Option name Description Valid Values Default Value
json.path One or more JsonPath expressions as filters. E.g. json.path=value or json.path.1, json.path.2, ... to add multiple expressions. The json.path option is only recommended if users need to filter a large JSON file, for example, in combination with the slice option. 
It will pre-process the JSON before the execution of the query. 
In most cases, it is easier to query the JSON using a triple pattern, as in the [example described before](#Example). | Any valid JsonPath (see [JsonSurfer implementation](https://github.com/jsurfer/JsonSurfer))) | Not set |

json.path

Description

One or more JsonPath expressions as filters. E.g. json.path=value or json.path.1, json.path.2, ... to add multiple expressions. The json.path option is only recommended if users need to filter a large JSON file, for example, in combination with the slice option. It will pre-process the JSON before the execution of the query. In most cases, it is easier to query the JSON using a triple pattern, as in the example described before.

Valid Values

Any valid JsonPath (see JsonSurfer implementation))

Default Value

Not set

Examples

Example 1

Retrieving the lists of stars of the TV Series named "Friends" and "Cougar Town".

Input
[
   {
      "name":"Friends",
      "genres":[
         "Comedy",
         "Romance"
      ],
      "language":"English",
      "status":"Ended",
      "premiered":"1994-09-22",
      "summary":"Follows the personal and professional lives of six twenty to thirty-something-year-old friends living in Manhattan.",
      "stars":[
         "Jennifer Aniston",
         "Courteney Cox",
         "Lisa Kudrow",
         "Matt LeBlanc",
         "Matthew Perry",
         "David Schwimmer"
      ]
   },
   {
      "name":"Cougar Town",
      "genres":[
         "Comedy",
         "Romance"
      ],
      "language":"English",
      "status":"Ended",
      "premiered":"2009-09-23",
      "summary":"Jules is a recently divorced mother who has to face the unkind realities of dating in a world obsessed with beauty and youth. As she becomes older, she starts discovering herself.",
      "stars":[
         "Courteney Cox",
         "David Arquette",
         "Bill Lawrence",
         "Linda Videtti Figueiredo",
         "Blake McCormick"
      ]
   }
]

https://sparql-anything.cc/example1.json

Query
PREFIX  xyz:  <http://sparql.xyz/facade-x/data/>
PREFIX  fx:   <http://sparql.xyz/facade-x/ns/>
PREFIX  rdf:  <http://www.w3.org/1999/02/22-rdf-syntax-ns#>

CONSTRUCT 
  { 
    ?s ?p ?o .
  }
WHERE
  { SERVICE <x-sparql-anything:location=https://sparql-anything.cc/example1.json>
      { fx:properties
                  fx:json.path.1  "$[?(@.name==\"Friends\")].stars" ;
                  fx:json.path.2  "$[?(@.name==\"Cougar Town\")].stars" .
        ?s        ?p              ?o
      }
  }
Result
PREFIX dc:     <http://purl.org/dc/elements/1.1/>
PREFIX eg:     <http://www.example.org/>
PREFIX fx:     <http://sparql.xyz/facade-x/ns/>
PREFIX ja:     <http://jena.hpl.hp.com/2005/11/Assembler#>
PREFIX owl:    <http://www.w3.org/2002/07/owl#>
PREFIX rdf:    <http://www.w3.org/1999/02/22-rdf-syntax-ns#>
PREFIX rdfs:   <http://www.w3.org/2000/01/rdf-schema#>
PREFIX rss:    <http://purl.org/rss/1.0/>
PREFIX vcard:  <http://www.w3.org/2001/vcard-rdf/3.0#>
PREFIX whatwg: <https://html.spec.whatwg.org/#>
PREFIX xhtml:  <http://www.w3.org/1999/xhtml#>
PREFIX xsd:    <http://www.w3.org/2001/XMLSchema#>
PREFIX xyz:    <http://sparql.xyz/facade-x/data/>

[ rdf:type  fx:root;
  rdf:_1    [ rdf:_1  "Jennifer Aniston";
              rdf:_2  "Courteney Cox";
              rdf:_3  "Lisa Kudrow";
              rdf:_4  "Matt LeBlanc";
              rdf:_5  "Matthew Perry";
              rdf:_6  "David Schwimmer"
            ];
  rdf:_2    [ rdf:_1  "Courteney Cox";
              rdf:_2  "David Arquette";
              rdf:_3  "Bill Lawrence";
              rdf:_4  "Linda Videtti Figueiredo";
              rdf:_5  "Blake McCormick"
            ]
] .
Example 2

Retrieving the language of the TV series named "Friends".

Input
[
   {
      "name":"Friends",
      "genres":[
         "Comedy",
         "Romance"
      ],
      "language":"English",
      "status":"Ended",
      "premiered":"1994-09-22",
      "summary":"Follows the personal and professional lives of six twenty to thirty-something-year-old friends living in Manhattan.",
      "stars":[
         "Jennifer Aniston",
         "Courteney Cox",
         "Lisa Kudrow",
         "Matt LeBlanc",
         "Matthew Perry",
         "David Schwimmer"
      ]
   },
   {
      "name":"Cougar Town",
      "genres":[
         "Comedy",
         "Romance"
      ],
      "language":"English",
      "status":"Ended",
      "premiered":"2009-09-23",
      "summary":"Jules is a recently divorced mother who has to face the unkind realities of dating in a world obsessed with beauty and youth. As she becomes older, she starts discovering herself.",
      "stars":[
         "Courteney Cox",
         "David Arquette",
         "Bill Lawrence",
         "Linda Videtti Figueiredo",
         "Blake McCormick"
      ]
   }
]

https://sparql-anything.cc/example1.json

Query
PREFIX  xyz:  <http://sparql.xyz/facade-x/data/>
PREFIX  fx:   <http://sparql.xyz/facade-x/ns/>
PREFIX  rdf:  <http://www.w3.org/1999/02/22-rdf-syntax-ns#>

SELECT  ?language
WHERE
  { SERVICE <x-sparql-anything:location=https://sparql-anything.cc/example1.json>
      { fx:properties
                  fx:json.path  "$[?(@.name==\"Friends\")]" .
        _:b0      xyz:language  ?language
      }
  }
Result
-------------
| language  |
=============
| "English" |
-------------
Example 3

Constructing a Facade-X RDF Graph selecting only containers that match the Json Path $[?(@.name==&quot;Friends&quot;)].

Input
[
   {
      "name":"Friends",
      "genres":[
         "Comedy",
         "Romance"
      ],
      "language":"English",
      "status":"Ended",
      "premiered":"1994-09-22",
      "summary":"Follows the personal and professional lives of six twenty to thirty-something-year-old friends living in Manhattan.",
      "stars":[
         "Jennifer Aniston",
         "Courteney Cox",
         "Lisa Kudrow",
         "Matt LeBlanc",
         "Matthew Perry",
         "David Schwimmer"
      ]
   },
   {
      "name":"Cougar Town",
      "genres":[
         "Comedy",
         "Romance"
      ],
      "language":"English",
      "status":"Ended",
      "premiered":"2009-09-23",
      "summary":"Jules is a recently divorced mother who has to face the unkind realities of dating in a world obsessed with beauty and youth. As she becomes older, she starts discovering herself.",
      "stars":[
         "Courteney Cox",
         "David Arquette",
         "Bill Lawrence",
         "Linda Videtti Figueiredo",
         "Blake McCormick"
      ]
   }
]

https://sparql-anything.cc/example1.json

Query
PREFIX  xyz:  <http://sparql.xyz/facade-x/data/>
PREFIX  fx:   <http://sparql.xyz/facade-x/ns/>
PREFIX  rdf:  <http://www.w3.org/1999/02/22-rdf-syntax-ns#>

CONSTRUCT 
  { 
    ?s ?p ?o .
  }
WHERE
  { SERVICE <x-sparql-anything:location=https://sparql-anything.cc/example1.json>
      { fx:properties
                  fx:json.path  "$[?(@.name==\"Friends\")]" .
        ?s        ?p            ?o
      }
  }
Result
PREFIX dc:     <http://purl.org/dc/elements/1.1/>
PREFIX eg:     <http://www.example.org/>
PREFIX fx:     <http://sparql.xyz/facade-x/ns/>
PREFIX ja:     <http://jena.hpl.hp.com/2005/11/Assembler#>
PREFIX owl:    <http://www.w3.org/2002/07/owl#>
PREFIX rdf:    <http://www.w3.org/1999/02/22-rdf-syntax-ns#>
PREFIX rdfs:   <http://www.w3.org/2000/01/rdf-schema#>
PREFIX rss:    <http://purl.org/rss/1.0/>
PREFIX vcard:  <http://www.w3.org/2001/vcard-rdf/3.0#>
PREFIX whatwg: <https://html.spec.whatwg.org/#>
PREFIX xhtml:  <http://www.w3.org/1999/xhtml#>
PREFIX xsd:    <http://www.w3.org/2001/XMLSchema#>
PREFIX xyz:    <http://sparql.xyz/facade-x/data/>

[ rdf:type  fx:root;
  rdf:_1    [ xyz:genres     [ rdf:_1  "Comedy";
                               rdf:_2  "Romance"
                             ];
              xyz:language   "English";
              xyz:name       "Friends";
              xyz:premiered  "1994-09-22";
              xyz:stars      [ rdf:_1  "Jennifer Aniston";
                               rdf:_2  "Courteney Cox";
                               rdf:_3  "Lisa Kudrow";
                               rdf:_4  "Matt LeBlanc";
                               rdf:_5  "Matthew Perry";
                               rdf:_6  "David Schwimmer"
                             ];
              xyz:status     "Ended";
              xyz:summary    "Follows the personal and professional lives of six twenty to thirty-something-year-old friends living in Manhattan."
            ]
] .