Trouble parsing JSON - json

Question

I am having trouble parsing some JSON in Swift. I am having trouble getting the errors variable it returns nil. I think it should be a dictionary?
Below is the JSON that is returned from my API as printed in the console.
{
error = "{\"name\":[\"The name has already been taken.\"],\"email\":[\"The email has already been taken.\"]}";
success = 0;
}
And here is the Swift code.
do {
let json = try JSONSerialization.jsonObject(with: data!, options: .mutableContainers) as? NSDictionary
if let parseJSON = json {
print(parseJSON)
let success = parseJSON["success"] as? Int
if(success == 1) {
let myAlert = UIAlertController(title: "Alert", message: "Registration successful", preferredStyle: UIAlertControllerStyle.alert);
let okAction = UIAlertAction(title: "OK", style: UIAlertActionStyle.default){
(action) in
self.dismiss(animated: true, completion: nil)
}
myAlert.addAction(okAction);
self.present(myAlert, animated: true, completion: nil)
} else {
let errors = parseJSON["error"] as? NSDictionary
if(errors != nil){
print("NOT NIL")
// self.displayAlertMessage()
}
}
}
} catch{
print(error)
}
EDIT
Here is the JSON thats is printed using David's code below.
This is the parseJSON printed to the console.
["error": {"name":["The name has already been taken."],"email":["The email has already been taken."]}, "success": 0]
Here is my full method with Davids updated code.
let task = URLSession.shared.dataTask(with: request) { (theData: Data?, response: URLResponse?, theError: Error?) in
DispatchQueue.main.async
{
//spinningActivity!.hide(true)
if theError != nil {
self.displayAlertMessage(theError!.localizedDescription)
return
}
do {
guard let parseJSON = try JSONSerialization.jsonObject(with: theData!) as? [String:Any] else {return}
//print(parseJSON)
let success = parseJSON["success"] as? Int
if(success == 1) {
let myAlert = UIAlertController(title: "Alert", message: "Registration successful", preferredStyle: UIAlertControllerStyle.alert);
let okAction = UIAlertAction(title: "OK", style: UIAlertActionStyle.default){
(action) in
self.dismiss(animated: true, completion: nil)
}
myAlert.addAction(okAction);
self.present(myAlert, animated: true, completion: nil)
} else {
guard let errors = parseJSON["success"] as? Int else {return}
print(errors)
}
} catch{
print(error)
}
}
}
task.resume()

Answer 1

There are several issues with your code that might be not causing the issue directly, but are bad practices. Don't use NSDictionary in Swift, use [String:Any] when decoding JSON responses and don't use .mutableContainers as it has no effect in Swift, the mutability is determined by the let or var keyword when declaring the variable.
Moreover, don't include console print as the JSON response, include the actual JSON response in your question, as Swift's print statement doesn't produce a valid JSON.
let apiErrorResponse = """
{
"error": {
"name": "The name has already been taken.",
"email": ["The email has already been taken."]
},
"success": 0
}
"""
func handleApiErrorResponse(){
do {
guard let parseJSON = try JSONSerialization.jsonObject(with: apiErrorResponse.data(using: .utf8)!) as? [String:Any] else {return}
let success = parseJSON["success"] as? Int
if(success == 1) {
let myAlert = UIAlertController(title: "Alert", message: "Registration successful", preferredStyle: UIAlertControllerStyle.alert);
let okAction = UIAlertAction(title: "OK", style: UIAlertActionStyle.default){
(action) in
self.dismiss(animated: true, completion: nil)
}
myAlert.addAction(okAction);
self.present(myAlert, animated: true, completion: nil)
} else {
guard let errors = parseJSON["error"] as? [String:Any] else {return}
print(errors)
}
} catch{
print(error)
}
}
handleApiErrorResponse()
Output:
"["name": The name has already been taken., "email": <__NSSingleObjectArrayI 0x608000019f80>(\nThe email has already been taken.\n)\n]\n"