checkoutEvent function
Implementation
Future<dynamic> checkoutEvent(CheckoutModel payload) async {
final commonParams = await getCommonParams();
payload.userId = payload.userId ?? commonParams['userId'];
payload.sessionId = payload.sessionId ?? commonParams['sessionId'];
payload.device = payload.device ?? commonParams['device'];
payload.os = payload.os ?? commonParams['os'];
payload.lang = payload.lang ?? commonParams['lang'];
final mappedPayload = payload.toMap();
final jsonPayload = convert.jsonEncode(mappedPayload);
return jsonPayload;
}