{
  "$schema": "http://json-schema.org/draft-07/schema#",
  "title": "Checkout Accepted",
  "description": "Response returned when checkout processing requires an additional payer action, such as a 3DS challenge or a redirect to an external payment method page.",
  "type": "object",
  "properties": {
    "next_step": {
      "description": "Instructions for the next action the payer or client must take.",
      "type": "object",
      "properties": {
        "url": {
          "description": "URL to open or submit in order to continue processing.",
          "type": "string",
          "example": "https://dummy-3ds-gateway.com/cap?RID=1233&VAA=A"
        },
        "method": {
          "description": "HTTP method to use when following the next step.",
          "type": "string",
          "example": "POST"
        },
        "redirect_url": {
          "description": "Merchant URL where the payer returns after the external flow finishes.",
          "type": "string",
          "example": "https://mysite.com/completed_purchase"
        },
        "mechanism": {
          "description": "Allowed presentation mechanisms for the next step. `iframe` means the flow can be embedded, while `browser` means it can be completed through a full-page redirect.",
          "type": "array",
          "items": {
            "type": "string",
            "enum": [
              "iframe",
              "browser"
            ]
          }
        },
        "payload": {
          "description": "Parameters required to complete the next step. The exact keys depend on the payment provider and flow type.",
          "type": "object",
          "example": {
            "PaReq": "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",
            "MD": "b1a536c0-29b9-11eb-adc1-0242ac120002",
            "TermUrl": "https://api.sumup.com/v0.1/checkouts/e552de3b-1777-4c91-bdb8-756967678572/complete_payment"
          },
          "additionalProperties": {
            "type": "string"
          }
        }
      }
    }
  }
}