{
  "$schema": "https://json-schema.org/draft/2020-12/schema",
  "type": "object",
  "properties": {
    "currency": {
      "type": "string",
      "enum": [
        "USD",
        "EUR",
        "GBP",
        "JPY"
      ]
    }
  },
  "required": [
    "currency"
  ]
}