{
  "$schema": "http://json-schema.org/draft-04/schema#",
  "$ref": "#/definitions/CompactDate",
  "definitions": {
    "CompactDate": {
      "pattern": "^[0-9]{4}-[0-1][0-9]$",
      "type": "string",
      "title": "Compact Date",
      "description": "Short date that only includes year and month"
    }
  }
}