{
  "$schema": "https://json-schema.org/draft/2020-12/schema",
  "$id": "https://offeringprotocol.org/schemas/filter-unit.schema.json",
  "title": "ODP filter unit",
  "oneOf": [
    {
      "type": "object",
      "required": [
        "system",
        "code"
      ],
      "properties": {
        "system": {
          "const": "ucum"
        },
        "code": {
          "type": "string",
          "minLength": 1,
          "maxLength": 64
        }
      }
    },
    {
      "type": "object",
      "required": [
        "system",
        "code",
        "title"
      ],
      "properties": {
        "system": {
          "const": "service"
        },
        "code": {
          "$ref": "capability-identifier.schema.json"
        },
        "title": {
          "type": "string",
          "minLength": 1,
          "maxLength": 128
        }
      }
    }
  ]
}