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QR Code Flow for Merchants

Connecting with patrons using our QR Code Flow requires the merchant integration to create a Payment Request  API  and present a QR Code for the patron to scan.

The sequence diagram below indicates the expected flow of behavior between the patron, the Point of Sale (POS) and Centrapay.

Loading Diagram...

  1. The POS creates a Payment Request  API  and presents a QR code to the Patron on a customer-facing display.

The QR code decodes to a URL of the form https://service.centrapay.com/api/payment-requests/{paymentRequestId}/pay

Request
POST/api/payment-requests
curl -X POST https://service.centrapay.com/api/payment-requests \
  -H "X-Api-Key: $api_key" \
  -H "Content-Type: application/json" \
  -d '{
    "configId": "5ee168e8597be5002af7b454",
    "value": {
      "amount": "10000",
      "currency": "NZD"
    }
  }'
Response
{
  "configId": "5ee168e8597be5002af7b454",
  "createdAt": "2021-06-08T04:04:27.426Z",
  "expiresAt": "2021-06-08T04:06:27.426Z",
  "expirySeconds": 120,
  "id": "MhocUmpxxmgdHjr7DgKoKw",
  "merchantId": "26d3Cp3rJmbMHnuNJmks2N",
  "merchantName": "Centrapay Café",
  "paymentOptions": [
    {
      "amount": "10000",
      "assetType": "centrapay.nzd.main"
    }
  ],
  "shortCode": "CP-C7F-ZS5",
  "status": "new",
  "updatedAt": "2021-06-08T04:04:27.426Z",
  "url": "https://app.centrapay.com/pay/MhocUmpxxmgdHjr7DgKoKw",
  "value": {
    "currency": "NZD",
    "amount": "10000"
  }
}
  1. The patron scans the QR code using a Centrapay-enabled app.
  2. The POS polls the Payment Request for  API  Payment Confirmation.
Request
GET/api/payment-requests/{paymentRequestId}
curl https://service.centrapay.com/api/payment-requests/MhocUmpxxmgdHjr7DgKoKw \
  -H "Authorization: $jwt"
Response
{
  "configId": "5ee168e8597be5002af7b454",
  "createdAt": "2021-06-08T04:04:27.426Z",
  "expiresAt": "2021-06-08T04:06:27.426Z",
  "expirySeconds": 120,
  "id": "MhocUmpxxmgdHjr7DgKoKw",
  "merchantId": "26d3Cp3rJmbMHnuNJmks2N",
  "merchantName": "Centrapay Café",
  "paymentOptions": [
    {
      "amount": "10000",
      "assetType": "centrapay.nzd.main"
    }
  ],
  "shortCode": "CP-C7F-ZS5",
  "status": "new",
  "updatedAt": "2021-06-08T04:04:27.426Z",
  "url": "https://app.centrapay.com/pay/MhocUmpxxmgdHjr7DgKoKw",
  "value": {
    "currency": "NZD",
    "amount": "10000"
  }
}
  1. While the POS continues to poll, the patron pays the Payment Request  API  via their Centrapay integrated app. When the Payment Request status is paid, the POS stops polling and displays confirmation of the successful payment.
Request
POST/api/payment-requests/{paymentRequestId}/pay
curl -X POST https://service.centrapay.com/api/payment-requests/MhocUmpxxmgdHjr7DgKoKw/pay \
  -H "Authorization: $jwt" \
  -H "Content-Type: application/json" \
  -d '{
    "assetType": "centrapay.nzd.main",
    "assetId": "WRhAxxWpTKb5U7pXyxQjjY"
  }'
Response
{
  "activityNumber": "2",
  "assetType": "centrapay.nzd.main",
  "createdAt": "2021-06-08T04:04:27.426Z",
  "createdBy": "crn::user:0af834c8-1110-11ec-9072-3e22fb52e878",
  "merchantAccountId": "C4QnjXvj8At6SMsEN4LRi9",
  "merchantConfigId": "5ee168e8597be5002af7b454",
  "merchantId": "26d3Cp3rJmbMHnuNJmks2N",
  "merchantName": "Centrapay Café",
  "paymentRequestCreatedBy": "crn::user:0af834c8-1110-11ec-9072-3e22fb52e878",
  "paymentRequestId": "MhocUmpxxmgdHjr7DgKoKw",
  "shortCode": "CP-C7F-ZS5-015",
  "type": "payment",
  "value": {
    "currency": "NZD",
    "amount": "10000"
  }
}