cloudkit how to write to public database - swift

Question

Iam using cloudkit to read and write in public database - in my application user suppose to be able to upload files and write records to database and other users to read it
I am using cloudkit however as far as I know to write to the public database user has to login with icloud account however apple does not allow this in production so how to solve this - how can I give the users a right to write to DB
let Container = CKContainer.default()
let database = Container.publicCloudDatabase
let predicate = NSPredicate(value: true)
let query = CKQuery(recordType: "NewCode", predicate: predicate) //Photos is table name in cloudkit server
//-------Fetch the data---------------------
database.perform(query, inZoneWith: nil,
completionHandler: ({results, error in
DispatchQueue.main.async() { //Disp
if (error != nil) {
DispatchQueue.main.async() {
}
}
else { //a
if results!.count > 0 {
print("count = \(results!.count)")
record = results![0]
currentRecord = record
newcode = currentRecord?.object(forKey: "Code") as! String
newcodevalue = Int(newcode)!
newcodevalue = newcodevalue + 10
print("new code is = \(newcodevalue)")
myCodeStrinValue = String(newcodevalue)
print("new code string = \(newcodevalue)")
record?.setObject(myCodeStrinValue as CKRecordValue?,forKey: "Code")
database.save(record!, completionHandler: //save
({returnRecord, error in
if let err = error {
DispatchQueue.main.async() {
}
} else {
DispatchQueue.main.async() {
print("NewCode Table updated successfully")
// passing the code value we fetched above to the second viewcontroller "Uploadphotoviewcontroller" to be saved with the uploaded photo when saved button on the second controller clicked. remember you have to set an ID for the second view controller "Uploadphotoviewcontroller" to be used here when passing the value to it (set ID in the attributes right panel
// Instantiate SecondViewController
let UploadPhotoviewcontroller = self.storyboard?.instantiateViewController(withIdentifier:
"UploadPhotoviewcontroller") as! UploadPhotoviewcontroller
// Set the code value got from the DB above to the variable "myCodeValue" (this variable declared in the second view controller that will receive the value passed from here "Uploadphotoviewcontroller"
// add alpha numeric value to the code to make it more complicated for secuirty reasons
let CodeLetter = self.randomAlphaNumericString (length: 3)
UploadPhotoviewcontroller.myCodeValue = CodeLetter + myCodeStrinValue
UploadPhotoviewcontroller.codeOnly = myCodeStrinValue
// Take user to SecondViewController and accordingly remember not create graphical sague way link in the main storyboard to avoid reload of the view controller - remember to set ID attribute to UploadPhotoviewcontroller to use it here
self.navigationController?.pushViewController(UploadPhotoviewcontroller, animated: true)
}
}
})) //save
}
else { //G
DispatchQueue.main.async()
{
}
} //G
} //a
} //Disp
}))