findByIdNumber method
Find client by its id number
Implementation
Future<Client?> findByIdNumber(String idNumber) async {
final response = await WebClient().get(
'${InvoiceNinjaAdmin.url}/api/v1/clients?id_number=$idNumber',
token: InvoiceNinjaAdmin.token);
final data = ClientList.fromJson(response).data;
return data.isEmpty ? null : data.first;
}