expressCart/config/payment/schema/payway.json

{
    "properties": {
        "apiKey": {
            "type": "string"
        },
        "publishableApiKey": {
            "type": "string"
        },
        "merchantId": {
            "type": "string"
        }
    },
    "required": [
        "apiKey",
        "publishableApiKey",
        "merchantId"
    ],
    "additionalProperties": false
}