{
  "$id": "rdf-triple.json",
  "$schema": "https://json-schema.org/draft/2020-12/schema",
  "title": "RDF Triple",
  "description": "Schema describing an RDF triple (statement) as the fundamental unit of data in the Resource Description Framework. A triple consists of a subject, predicate, and object that together express a relationship between resources.",
  "type": "object",
  "required": [
    "subject",
    "predicate",
    "object"
  ],
  "properties": {
    "subject": {
      "type": "string",
      "description": "The resource being described, expressed as an IRI (Internationalized Resource Identifier) or blank node identifier.",
      "format": "uri"
    },
    "predicate": {
      "type": "string",
      "description": "The property or relationship connecting the subject to the object, expressed as an IRI.",
      "format": "uri"
    },
    "object": {
      "oneOf": [
        {
          "type": "string",
          "description": "An IRI reference to another resource.",
          "format": "uri"
        },
        {
          "$ref": "#/$defs/literal"
        }
      ],
      "description": "The value or resource that the subject is related to via the predicate. Can be an IRI, blank node, or literal value."
    }
  },
  "additionalProperties": false,
  "$defs": {
    "literal": {
      "type": "object",
      "description": "An RDF literal value with optional datatype and language tag.",
      "required": [
        "value"
      ],
      "properties": {
        "value": {
          "type": "string",
          "description": "The lexical form of the literal."
        },
        "datatype": {
          "type": "string",
          "description": "The IRI identifying the datatype of the literal, defaulting to xsd:string.",
          "format": "uri"
        },
        "language": {
          "type": "string",
          "description": "A BCP47 language tag for language-tagged strings.",
          "pattern": "^[a-zA-Z]{1,8}(-[a-zA-Z0-9]{1,8})*$"
        }
      },
      "additionalProperties": false
    }
  }
}