{
    "$schema": "http://json-schema.org/draft-07/schema#",
    "type": "object",
    "properties": {
        "type": {
            "type": "string",
            "enum": [ "debit", "credit" ]
        },
        "order_id": {
            "type": "integer",
            "minimum": 1
        },
        "invoice_number": {
            "type": "integer",
            "minimum": 1
        }
    },
    "required": [ "type", "order_id", "invoice_number" ]
}