Swift Alamofire: How to get the HTTP response status code
SwiftAlamofireSwift Problem Overview
I would like to retrieve the HTTP response status code (e.g. 400, 401, 403, 503, etc) for request failures (and ideally for successes too). In this code, I am performing user authentication with HTTP Basic and want to be able to message the user that authentication failed when the user mistypes their password.
Alamofire.request(.GET, "https://host.com/a/path").authenticate(user: "user", password: "typo")
.responseString { (req, res, data, error) in
if error != nil {
println("STRING Error:: error:\(error)")
println(" req:\(req)")
println(" res:\(res)")
println(" data:\(data)")
return
}
println("SUCCESS for String")
}
.responseJSON { (req, res, data, error) in
if error != nil {
println("JSON Error:: error:\(error)")
println(" req:\(req)")
println(" res:\(res)")
println(" data:\(data)")
return
}
println("SUCCESS for JSON")
}
Unfortunately, the error produced does not seem to indicate that an HTTP status code 409 was actually received:
STRING Error:: error:Optional(Error Domain=NSURLErrorDomain Code=-999 "cancelled" UserInfo=0x7f9beb8efce0 {NSErrorFailingURLKey=https://host.com/a/path, NSLocalizedDescription=cancelled, NSErrorFailingURLStringKey=https://host.com/a/path})
req:<NSMutableURLRequest: 0x7f9beb89d5e0> { URL: https://host.com/a/path }
res:nil
data:Optional("")
JSON Error:: error:Optional(Error Domain=NSURLErrorDomain Code=-999 "cancelled" UserInfo=0x7f9beb8efce0 {NSErrorFailingURLKey=https://host.com/a/path, NSLocalizedDescription=cancelled, NSErrorFailingURLStringKey=https://host.com/a/path})
req:<NSMutableURLRequest: 0x7f9beb89d5e0> { URL: https://host.com/a/path }
res:nil
data:nil
Additionally, it would be nice to retrieve the HTTP body when an error occurs because my server-side will put a textual description of the error there.
Questions
Is it possible to retrieve the status code upon a non-2xx response?
Is it possible to retrieve the specific status code upon a 2xx response?
Is it possible to retrieve the HTTP body upon a non-2xx response?
Thanks!
Swift Solutions
Solution 1 - Swift
For Swift 3.x / Swift 4.0 / Swift 5.0 users with Alamofire >= 4.0 / Alamofire >= 5.0
response.response?.statusCode
More verbose example:
Alamofire.request(urlString)
.responseString { response in
print("Success: \(response.result.isSuccess)")
print("Response String: \(response.result.value)")
var statusCode = response.response?.statusCode
if let error = response.result.error as? AFError {
statusCode = error._code // statusCode private
switch error {
case .invalidURL(let url):
print("Invalid URL: \(url) - \(error.localizedDescription)")
case .parameterEncodingFailed(let reason):
print("Parameter encoding failed: \(error.localizedDescription)")
print("Failure Reason: \(reason)")
case .multipartEncodingFailed(let reason):
print("Multipart encoding failed: \(error.localizedDescription)")
print("Failure Reason: \(reason)")
case .responseValidationFailed(let reason):
print("Response validation failed: \(error.localizedDescription)")
print("Failure Reason: \(reason)")
switch reason {
case .dataFileNil, .dataFileReadFailed:
print("Downloaded file could not be read")
case .missingContentType(let acceptableContentTypes):
print("Content Type Missing: \(acceptableContentTypes)")
case .unacceptableContentType(let acceptableContentTypes, let responseContentType):
print("Response content type: \(responseContentType) was unacceptable: \(acceptableContentTypes)")
case .unacceptableStatusCode(let code):
print("Response status code was unacceptable: \(code)")
statusCode = code
}
case .responseSerializationFailed(let reason):
print("Response serialization failed: \(error.localizedDescription)")
print("Failure Reason: \(reason)")
// statusCode = 3840 ???? maybe..
default:break
}
print("Underlying error: \(error.underlyingError)")
} else if let error = response.result.error as? URLError {
print("URLError occurred: \(error)")
} else {
print("Unknown error: \(response.result.error)")
}
print(statusCode) // the status code
}
(Alamofire 4 contains a completely new error system, look here for details)
For Swift 2.x users with Alamofire >= 3.0
Alamofire.request(.GET, urlString)
.responseString { response in
print("Success: \(response.result.isSuccess)")
print("Response String: \(response.result.value)")
if let alamoError = response.result.error {
let alamoCode = alamoError.code
let statusCode = (response.response?.statusCode)!
} else { //no errors
let statusCode = (response.response?.statusCode)! //example : 200
}
}
Solution 2 - Swift
In the completion handler with argument response below I find the http status code is in response.response.statusCode:
Alamofire.request(.POST, urlString, parameters: parameters)
.responseJSON(completionHandler: {response in
switch(response.result) {
case .Success(let JSON):
// Yeah! Hand response
case .Failure(let error):
let message : String
if let httpStatusCode = response.response?.statusCode {
switch(httpStatusCode) {
case 400:
message = "Username or password not provided."
case 401:
message = "Incorrect password for user '\(name)'."
...
}
} else {
message = error.localizedDescription
}
// display alert with error message
}
Solution 3 - Swift
Alamofire
.request(.GET, "REQUEST_URL", parameters: parms, headers: headers)
.validate(statusCode: 200..<300)
.responseJSON{ response in
switch response.result{
case .Success:
if let JSON = response.result.value
{
}
case .Failure(let error):
}
Solution 4 - Swift
Best way to get the status code using alamofire.
Alamofire.request(URL).responseJSON {
response in
let status = response.response?.statusCode
print("STATUS (status)")
}
Solution 5 - Swift
Or use pattern matching
if let error = response.result.error as? AFError {
if case .responseValidationFailed(.unacceptableStatusCode(let code)) = error {
print(code)
}
}
Solution 6 - Swift
you may check the following code for status code handler by alamofire
let request = URLRequest(url: URL(string:"url string")!)
Alamofire.request(request).validate(statusCode: 200..<300).responseJSON { (response) in
switch response.result {
case .success(let data as [String:Any]):
completion(true,data)
case .failure(let err):
print(err.localizedDescription)
completion(false,err)
default:
completion(false,nil)
}
}
if status code is not validate it will be enter the failure in switch case
Solution 7 - Swift
In your responseJSON completion, you can get the status code from the response object, which has a type of NSHTTPURLResponse?:
if let response = res {
var statusCode = response.statusCode
}
This will work regardless of whether the status code is in the error range. For more information, take a look at the [NSHTTPURLResponse documentation][1].
For your other question, you can use the responseString function to get the raw response body. You can add this in addition to responseJSON and both will be called.
.responseJson { (req, res, json, error) in
// existing code
}
.responseString { (_, _, body, _) in
// body is a String? containing the response body
}
[1]: https://developer.apple.com/library/mac/documentation/Cocoa/Reference/Foundation/Classes/NSHTTPURLResponse_Class/ "documentation"
Solution 8 - Swift
Your error indicates that the operation is being cancelled for some reason. I'd need more details to understand why. But I think the bigger issue may be that since your endpoint https://host.com/a/path is bogus, there is no real server response to report, and hence you're seeing nil.
If you hit up a valid endpoint that serves up a proper response, you should see a non-nil value for res (using the techniques Sam mentions) in the form of a NSURLHTTPResponse object with properties like statusCode, etc.
Also, just to be clear, error is of type NSError. It tells you why the network request failed. The status code of the failure on the server side is actually a part of the response.
Hope that helps answer your main question.
Solution 9 - Swift
I needed to know how to get the actual error code number.
I inherited a project from someone else and I had to get the error codes from a .catch clause that they had previously setup for Alamofire:
} .catch { (error) in
guard let error = error as? AFError else { return }
guard let statusCode = error.responseCode else { return }
print("Alamofire statusCode num is: ", statusCode)
}
Or if you need to get it from the response value follow @mbryzinski's answer
Alamofire ... { (response) in
guard let error = response.result.error as? AFError else { return }
guard let statusCode = error.responseCode else { return }
print("Alamofire statusCode num is: ", statusCode)
})
Solution 10 - Swift
For Swift 2.0 users with Alamofire > 2.0
Alamofire.request(.GET, url)
.responseString { _, response, result in
if response?.statusCode == 200{
//Do something with result
}
}
Solution 11 - Swift
For Swift 3.x / Swift 4.0 / Swift 5.0 users with Alamofire >= 5.0
Used request modifier to increase and decrease the timeout interval.
Alamofire's request creation methods offer the most common parameters for customization but sometimes those just aren't enough. The URLRequests created from the passed values can be modified by using a RequestModifier closure when creating requests. For example, to set the URLRequest's timeoutInterval to 120 seconds, modify the request in the closure.
var manager = Session.default
manager.request(urlString, method: method, parameters: dict, headers: headers, requestModifier: { $0.timeoutInterval = 120 }).validate().responseJSON { response in
OR
RequestModifiers also work with trailing closure syntax.
var manager = Session.default
manager.request("https://httpbin.org/get") { urlRequest in
urlRequest.timeoutInterval = 60
urlRequest.allowsConstrainedNetworkAccess = false
}
.response(...)