Access JSON value from Alamofire response - ios

Question

I am making a request to a local server that returns the following JSON:
{"session_key":"somecodexyz1234"}
The following code is is used to attempt to print the session_key value. But this is always evaluated tonil`.
Alamofire.request(url, method: .post, parameters: parameters).responseJSON(completionHandler: {
response in
print("Request: \(String(describing: response.request))")
print("Response: \(String(describing: response.response))")
print("Response code: \(String(describing: response.response?.statusCode))")
if let data = response.data, let utf8Text = String(data: data, encoding: .utf8) {
print("Data: \(utf8Text)") // original server data as UTF8 string
}}
if response.data != nil {
let json = JSON(data: response.data!)
// changes
if let arr : NSArray = json as? NSArray
{
let sk = arr.value(forKey: "session_key") as? String
if sk != nil {print(sk)}
}
}
The following is output (the print(sk) is not executed as it is nil):
Request: Optional(http://127.0.0.1:5000/code)
Response: Optional(<NSHTTPURLResponse: 0x60800023f260> { URL: http://127.0.0.1:5000/code } { status code: 200, headers {
"Content-Length" = 40;
"Content-Type" = "application/json";
Date = "Sat, 23 Sep 2017 06:02:25 GMT";
Server = "Werkzeug/0.12.2 Python/3.4.3";
} })
Response code: Optional(200)
Data: "{\"session_key\":\"somecodexyz1234\"}"

Answer 1

Use below code to get response from almofire in json. In Your code, your are directly checking response.data instead of first check response.result as below.
Alamofire.request(requestURL, method:.post, parameters: param as? Parameters, encoding: URLEncoding(destination: .httpBody), headers: headers).responseJSON(completionHandler: { (response) in
switch response.result
{
case .success(let responseJSON):
// If request success then you will get response in json here
if responseJSON is String{
print("Reponse is string")
}
else if responseJSON is NSDictionary{
print("Reponse is Dictionary")
}
else if responseJSON is NSArray{
print("Reponse is Array")
}
else{
print("Any object")
return
}
print("Response : \((dicResponse)")
break
case .failure(let error):
// If request is failure then got error here.
break
}
})

Answer 2

You are using SwiftyJSON so why you again convert let arr : NSArray = json as? NSArray like this. You can simply do like this.
Alamofire.request(url, method: .post, parameters: parameters).responseJSON(completionHandler: {
response in
print("Request: \(String(describing: response.request))")
print("Response: \(String(describing: response.response))")
print("Response code: \(String(describing: response.response?.statusCode))")
if response.result.isSuccess, let result = response.result.value {
let json = JSON(result)
// Here is your session key
let sk = json["session_key"].stringValue
} else {
//Failure
}
})