Invoice issue

Additional parameters can be transferred in the request, for example:

• description – invoice description,
• phone – phone number linked to the wallet;
• account – card number;

The list of these parameters depends on the payway (payway). The required additional parameters for the payway can be found in the request “Getting payment methods for input” shop_input_config/shop in the add_ons_config response field.

Redirecting to invoice payment forms

If the request is successful, API will return the parameters necessary to redirect the user to the payment system for payment. These parameters will be in the data field of the response. The data.data field contains the parameters to be transferred during redirection (in the form of GET or POST request parameters).

The redirection method depends on the method parameter. The generated request must be sent to the URL specified in the url field of the data field.

For example, if you receive a POST in the method parameter to redirect a client to pay an invoice, you need to generate an HTML form from the parameters received in the response body (these parameters will differ for different payment systems).

An example of forming an HTML form using the jinja2 template language:

<form method="POST" action="{{ data['url'] }}">
    {% for param, value in data['data'].items() %}
      <input name="{{ param }}" value="{{ value }}" />
    {% endfor %}
</form>

For the data specified in the example response below, the following HTML form will be obtained:

<form method="POST" action="https://example.checkout.com/form/">
  <input name="transaction_id" value="1231" />
  <input name="payment_type" value="card" />
  <input name="fail_url" value="https://example.com/payment/?status=fail" />
  <input name="success_url" value="https://example.com/payment/?status=success" />
  <input type="submit" />
</form>

In case of "method": "GET" it is required to perform HTTP redirect to the URL with the parameters (using percent‐encoding), received in the data.data response field.

The URL is generated according to the following algorithm:

import urllib.parse
redirect_url = '{url}?{parameters}'.format(url=data['url'], parameters=urllib.parse.urlencode(data['data']))

An example of the formed URL: https://example.checkout.com/form/?transaction_id=1231&payment_type=card&fail_url=https%3A%2F%2Fexample.com%2Fpayment%2F%3Fstatus%3Dfail&success_url=https%3A%2F%2Fexample.com%2Fpayment%2F%3Fstatus%3Dsuccess

Payer Browser Authentication for 3D Secure

For 3ds 2.0 payments with card data to be successful, the payer’s browser information must be collected.

You can collect the data yourself or let our service perform this for you. If you collect the data on your end, please ensure that all the necessary values are included to the payment initiation request /invoice/create.

As an example, the provided JavaScript code could be employed to obtain the Payer Browser information. Please be aware that the client_info fields provided below do not include browser_accept_header.

let client_info = {
    "browser_java_enabled": window.navigator.javaEnabled(),
    "browser_javascript_enabled": true,
    "browser_language": window.navigator.language,
    "browser_color_depth": window.screen.colorDepth.toString(),
    "browser_screen_height": window.screen.height.toString(),
    "browser_screen_width": window.screen.width.toString(),
    "browser_tz": (new Date()).getTimezoneOffset().toString(),
    "browser_user_agent": window.navigator.userAgent,
    "challenge_window_size": "05"
}

If the payer’s browser data is not provided in the /invoice/create request, it will be necessary to redirect the payer to our service as an intermediate step using a data object, so that our service can collect the necessary browser data. See Redirecting to invoice payment forms for the details on redirect.