An Object Representation of an EDTF Date

csl-edtf-date.json

{
  "title": "CSL EDTF Date Definitions",
  "$schema": "http://json-schema.org/draft-07/schema#",
  "description": "CSL supports EDTF levels 0 and 1.",
  "definitions": {
    "date-object": {
      "title": "Date Object",
      "description": "An EDTF date represented as an object.",
      "date-parts": {
        "type": "array",
        "items": [
          {
            "type": "integer",
            "description": "year",
            "pattern": "[0-9]{4}"
          },
          {
            "type": "integer",
            "description": "month or season FIX",
            "pattern": "[1,2]{1,2}"
          },
          {
            "type": "integer",
            "description": "day",
            "pattern": "([1-9]|[12][0-9]|3[01])"
          }
        ],
        "minItems": 1,
        "maxItems": 3
      },
      "literal": {
        "title": "Literal date",
        "description": "A date that should be passed through to the processor as is; for dates that cannot be represented in EDTF.",
        "examples": ["Han Dynasty"],
        "type": "string"
      },
      "approximate": {
        "title": "Approximate",
        "description": "Indicates an approximate or circa date, which may be presented as `circa May 23, 1972`.",
        "type": "boolean"
      },
      "uncertain": {
        "title": "Uncertain",
        "description": "Indicates uncertainty about a date representation, which may be presented as `May 23, 1972?`",
        "type": "boolean"
      }
    },
    "required": ["date-parts"]
  },
  "date-range": {
    "title": "Date Range",
    "description": "An open end or begin of the range can be represented with a null.",
    "type": "array",
    "items": {
      "$ref": "#definitions/date-object"
    },
    "minItems": 2,
    "maxItems": 2
  },
  "edtf-string": {
    "title": "EDTF string",
    "description": "Dates represented as an EDTF string.",
    "examples": ["2014-21/2014-22","1936-03-25~"],
    "type": "string",
    "pattern": "^[0-9-%~X?.\/]{4,}$"
  },
}

TODO:

1. Open ends needs to be settled
2. regex patterns on the values
3. literal?