Error while parsing JSON data received via Alamofire (Swift) - ios

Question

I'm working with a non-profit organisation to help them develop a mobile application for their website (so they provided me with the backend services, etc)
Their login PHP service accepts data in JSON, and returns a true or false value in the form of JSON data, but I'm having trouble processing the response in Swift. I'm using Alamofire to connect to the HTTP service.
I'm attaching my code and the exception message I'm receiving below, would really appreciate some help
func authenticateUser (un: String, pw: String) -> Bool
{
var checker = false
let jsonDict : [String: String] = ["volunteer_email": un, "volunteer_pass": pw]
Alamofire.request("www.sampleurl.com/login.php", method: .post, parameters: jsonDict, encoding: JSONEncoding.default, headers: nil).responseJSON { (response:DataResponse<Any>) in
switch(response.result) {
case .success(_):
if response.result.value != nil{
print (response.result.value)
let resp = response.result.value as! NSDictionary
let results = resp["status"] as! [[String:Any]]
//Change the boolean value of checker based on the value of the results constant
print (results)
}
break
case .failure(_):
print(response.result.error)
break
}
}
return checker;
}
Log:
Optional(<__NSSingleObjectArrayI 0x600000009b50>( {
status = false; } ) ) Could not cast value of type '__NSSingleObjectArrayI' (0x10e28c528) to 'NSDictionary'
(0x10e28d1a8). 2018-05-09 12:13:00.177091+0530 TestApp1 [16680:817883]
Could not cast value of type '__NSSingleObjectArrayI' (0x10e28c528) to
'NSDictionary' (0x10e28d1a8). (lldb)
Log for response.result.value:
Note: "status":"false"/"true" is the output from the web service
Optional(<__NSSingleObjectArrayI 0x60400001b160>(
{
status = false;
}
))
Note: I did some research and I understood what the NSSingleObjectArray is and what causes it, but I'm stuck here as the service passes back only a single JSON value to my app. Is there any way to handle this without requesting the organisation to change their code? Logically, shouldn't I be able to cast the response into an NSDictionary regardless of its size?
Also, the reason why I've specified that the returned data can be of type any, is because I ran into an issue that can be found here:
Other StackOverflow question
Thanks so much in advance :)

Answer 1

Since you're using .responseJSON of Alamofire, you should make use of Alamofire's parameterized enums. It provides the json object in .success. So doing case .success(_) is wasteful.
Go ahead with this and no need of typecasting response.result.value at all.
Alamofire
.request("www.sampleurl.com/login.php",
method: .post,
parameters: jsonDict,
encoding: JSONEncoding.default,
headers: nil)
.responseJSON { (response) in
switch(response.result) {
case .success(let responseJSON):
print(responseJSON)
/*
As an improvement:
To obtain an easy-access object, convert responseJSON to either a:
1. Codable model:
let model = JSONDecoder().decode(SomeModel.self,
from: responseJSONData)
2. SwiftyJSON object: (available on GitHub)
let json = JSON(responseJSON)
Doing so will basically make accessing the inner elements easier.
*/...
case .failure(let error):
print(error)
}
}
BTW, just FYI: the response is an array of dictionaries, not a dictionary of array of dictionaries.

Answer 2

Use NSArray instead of NSDictionary
func authenticateUser (un: String, pw: String) -> Bool{
var checker = false
let jsonDict : [String: String] = ["volunteer_email": un, "volunteer_pass": pw]
Alamofire.request("www.sampleurl.com/login.php", method: .post, parameters: jsonDict, encoding: JSONEncoding.default, headers: nil).responseJSON { (response:DataResponse<Any>) in
switch(response.result) {
case .success(_):
if response.result.value != nil{
print (response.result.value)
let resp = response.result.value as! NSArray
let results = resp["status"] as! [[String:Any]]
//Change the boolean value of checker based on the value of the results constant
print (results)
}
break
case .failure(_):
print(response.result.error)
break
}
}
return checker;
}