How to pass JSON `null` value to `nil` value in swift? - ios

Question

I have this json wherein hospitalNumber has value and there is instances that it returns null value. The hospitalNumber has significance since its a part of the parameter needed for the endpoint in API. Please see sample json:
{
"responseMessage": "Request successful",
"data": [
{
"hospitalNumber": null,
"patientName": "Manual Entry",
"totalAmount": 10339.8000,
"manualEntry": true
},
{
"hospitalNumber": "1111111",
"patientName": "test patient",
"totalAmount": 932.5000,
"manualEntry": false
}
]
}
And below is my APIService for the endpoint that will pull the json above.
typealias getPatientDetailsPerPayoutTaskCompletion = (_ patientDetailsPerPayout: [PatientPayoutDetails]?, _ error: NetworkError?) -> Void
//Patient procedure details per patient
//parameterName is .searchByHospitalNumber = "hospitalNumber"
static func getPatientDetailsPerPayout(periodId: Int, doctorNumber: String, parameterName: PatientParameter, hospitalNumber: String, manualEntry: Bool, completion: #escaping getPatientDetailsPerPayoutTaskCompletion) {
guard let patientDetailsPerPayoutURL = URL(string: "\(Endpoint.Patient.patientProcedureDetails)?periodId=\(periodId)&doctorNumber=\(doctorNumber)\(parameterName.rawValue)\(hospitalNumber)&manualEntry=\(manualEntry)") else {
completion(nil, .invalidURL)
return
}
let sessionManager = Alamofire.SessionManager.default
sessionManager.session.getAllTasks { (tasks) in
tasks.forEach({ $0.cancel() })
}
Alamofire.request(patientDetailsPerPayoutURL, method: .get, encoding: JSONEncoding.default).responseJSON { (response) in
print(patientDetailsPerPayoutURL)
guard HelperMethods.reachability(responseResult: response.result) else {
completion(nil, .noNetwork)
return
}
guard let statusCode = response.response?.statusCode else {
completion(nil, .noStatusCode)
return
}
switch(statusCode) {
case 200:
guard let jsonData = response.data else {
completion(nil, .invalidJSON)
return
}
let decoder = JSONDecoder()
do {
let patientDetailsPayout = try decoder.decode(RootPatientPayoutDetails.self, from: jsonData)
if (patientDetailsPayout.data?.isEmpty)! {
completion(nil, .noRecordFound)
} else {
completion(patientDetailsPayout.data, nil)
}
} catch {
completion(nil, .invalidJSON)
}
case 400: completion(nil, .badRequest)
case 404: completion(nil, .noRecordFound)
default:
print("**UNCAPTURED STATUS CODE FROM (getPatientDetailsPayout)\nSTATUS CODE: \(statusCode)")
completion(nil, .uncapturedStatusCode)
}
}
}
getPatientPayoutDetails Function
func getPerPatientPayoutDetails(from: String, manualEntry: Bool) {
//SVProgressHUD.setDefaultMaskType(.black)
//SVProgressHUD.setForegroundColor(.white)
SVProgressHUD.setBackgroundColor(.lightGray)
SVProgressHUD.show(withStatus: "Retrieving Patient Procedures")
APIService.PatientList.getPatientDetailsPerPayout(periodId: doctorPayoutWeek[3].periodId!, doctorNumber: doctorNumber, parameterName: .selectedByHospitalNumber, hospitalNumber: from, manualEntry: manualEntry) { (patientPayout, error) in
guard let patientPerPayoutDetails = patientPayout, error == nil else {
if let networkError = error {
switch networkError {
case .noRecordFound:
let alertController = UIAlertController(title: "No Record Found", message: "You don't have current payment remittance", preferredStyle: .alert)
alertController.addAction(UIAlertAction(title: "OK", style: .default))
case .noNetwork:
let alertController = UIAlertController(title: "No Network", message: "\(networkError.rawValue)", preferredStyle: .alert)
alertController.addAction(UIAlertAction(title: "OK", style: .default))
self.present(alertController, animated: true, completion: nil)
default:
let alertController = UIAlertController(title: "Error", message: "There is something went wrong. Please try again", preferredStyle: .alert)
alertController.addAction(UIAlertAction(title: "OK", style: .default))
self.present(alertController, animated: true, completion: nil)
}
}
SVProgressHUD.dismiss()
return
}
self.selectedPatientPayment = patientPerPayoutDetails
print(self.selectedPatientPayment)
SVProgressHUD.dismiss()
return
}
}
tableView
func tableView(_ tableView: UITableView, didSelectRowAt indexPath: IndexPath) {
switch indexPath.section {
case 0: break
case 1: break
case 2:
filteredPatient = indexPath.row
let selectedpatient = patientList[filteredPatient].hospitalNumber
let selectedEntry = patientList[filteredPatient].manualEntry
self.isBrowseAll = false
getPerPatientPayoutDetails(from: selectedpatient!, manualEntry: selectedEntry)
default: break
}
}
The endpoint which requires null string in hospitalNumber when it is nil
https://sample.com/openapi/getpatientpayoutdetails?periodId=579&doctorNumber=2866&hospitalNumber=null&manualEntry=true
As you can see hospital number has an important role for the endpoint. My problem is, once the tableView has reloaded it shows the data properly but when I didSelect the cell with null hospitalNumber, my app crashes and show Found nil error since hospitalNumber has null value. Hope you understand what I am trying to explain, please help me. Thank you

Answer 1

Your Codable model is correct, all you need is guard-let/if-let to prevent crash:
if let selectedpatient = patientList[filteredPatient].hospitalNumber, let selectedEntry = patientList[filteredPatient].manualEntry {
self.isBrowseAll = false
getPerPatientPayoutDetails(from: selectedpatient, manualEntry: selectedEntry)
}
Updated:
If you want to create endPoint in case of nil also then use coalescing operator :
getPerPatientPayoutDetails(from: selectedpatient ?? "null", manualEntry: selectedEntry)

Answer 2

In didSelect do like
let selectedpatient:String! //or Int whatever type it is right not this line initializes selected patient with nil
//below line will check for nil and ALSO NULL if NULL or nil it will not reassigne selectedpatient which means selectedpatient will remain nil
if let hsptlNbr = patientList[filteredPatient].hospitalNumber as? yourDataType{
selectedpatient = hsptlNbr
}
after this you can pass this as nil or value if exist in below method
getPerPatientPayoutDetails(from: selectedpatient, manualEntry: selectedEntry)
Change func getPerPatientPayoutDetails(from: String, manualEntry: Bool)
to
func getPerPatientPayoutDetails(from: String?, manualEntry: Bool)