{
  "$id": "rdf-dataset.json",
  "$schema": "https://json-schema.org/draft/2020-12/schema",
  "title": "RDF Dataset",
  "description": "Schema describing an RDF dataset, which consists of a default graph and zero or more named graphs. Datasets are used to organize and partition RDF data into distinct graph contexts, as defined in the RDF 1.1 specification.",
  "type": "object",
  "properties": {
    "defaultGraph": {
      "type": "array",
      "description": "The default (unnamed) graph of the dataset containing a collection of RDF quads without an explicit graph name.",
      "items": {
        "$ref": "#/$defs/quad"
      }
    },
    "namedGraphs": {
      "type": "object",
      "description": "A map of graph names (IRIs) to arrays of quads, representing the named graphs in the dataset.",
      "additionalProperties": {
        "type": "array",
        "items": {
          "$ref": "#/$defs/quad"
        }
      }
    }
  },
  "additionalProperties": false,
  "$defs": {
    "quad": {
      "type": "object",
      "description": "An RDF quad representing a triple within a specific graph context.",
      "required": [
        "subject",
        "predicate",
        "object"
      ],
      "properties": {
        "subject": {
          "$ref": "#/$defs/term",
          "description": "The subject of the statement, an IRI or blank node."
        },
        "predicate": {
          "$ref": "#/$defs/term",
          "description": "The predicate of the statement, always an IRI."
        },
        "object": {
          "$ref": "#/$defs/term",
          "description": "The object of the statement, an IRI, blank node, or literal."
        },
        "graph": {
          "$ref": "#/$defs/term",
          "description": "The graph name for this quad, an IRI identifying the named graph."
        }
      },
      "additionalProperties": false
    },
    "term": {
      "type": "object",
      "description": "An RDF term representing a node or value in the graph.",
      "required": [
        "termType",
        "value"
      ],
      "properties": {
        "termType": {
          "type": "string",
          "description": "The type of this RDF term.",
          "enum": [
            "NamedNode",
            "BlankNode",
            "Literal",
            "DefaultGraph"
          ]
        },
        "value": {
          "type": "string",
          "description": "The value of the term: an IRI for NamedNode, identifier for BlankNode, or lexical form for Literal."
        },
        "language": {
          "type": "string",
          "description": "The language tag for language-tagged literal values.",
          "pattern": "^[a-zA-Z]{1,8}(-[a-zA-Z0-9]{1,8})*$"
        },
        "datatype": {
          "type": "object",
          "description": "The datatype of a literal term.",
          "properties": {
            "termType": {
              "type": "string",
              "const": "NamedNode"
            },
            "value": {
              "type": "string",
              "description": "The IRI of the datatype.",
              "format": "uri"
            }
          }
        }
      },
      "additionalProperties": false
    }
  }
}