Alamofire RequestRetrier with timeout error handling - ios

Question

I'm using RequestRetrier to automatically renew access_token for my API. But in each request function I would like to catch timeout error, but .case(let error) in .responseJSON body never executes, because of (I guess) retrier that I add to my accessSessionManager. Here's how it looks like:
lazy var accessSessionManager: SessionManager = {
let configuration = URLSessionConfiguration.default
configuration.timeoutIntervalForRequest = Configuration.timeout
configuration.timeoutIntervalForResource = Configuration.timeout
let sessionManager = Alamofire.SessionManager(configuration: configuration)
let oAuth2Handler = OAuth2Handler()
sessionManager.retrier = oAuth2Handler
sessionManager.adapter = oAuth2Handler
return sessionManager
}()
func changeName(newName: String,completionHandler: ((_ success: Bool, _ error: String?) -> ())?) {
guard let accessToken = self.getAccessToken() else { return }
let parameters = ["access_token": accessToken, "name": newName] as [String : Any]
self.accessSessionManager.request(Constants.nameUrl, method: .get, parameters: parameters).responseJSON { response in
switch response.result {
case .success(let json):
let jsonDict = JSON(json)
if let success = jsonDict["success"].bool {
completionHandler?(success, nil)
}
case .failure(let error):
if error._code == NSURLErrorTimedOut {
completionHandler?(false, "Please check your Internet connection and try again!")
} else if response.response?.statusCode == 400 {
completionHandler?(false, "Sorry, name not found")
} else if response.response?.statusCode != 401 {
completionHandler?(false, error.localizedDescription)
}
}
}
}
}
....
....
class OAuth2Handler {
//MARK: - Adapter
func adapt(_ urlRequest: URLRequest) throws -> URLRequest {
if let url = urlRequest.url {
guard let accessToken = self.getAccessToken() else { return urlRequest }
let newUrl = addOrUpdateQueryStringParameter(url: "\(url)", key: "access_token", value: accessToken)
let newRequest = URLRequest(url: URL(string: newUrl)!)
return newRequest
}
return urlRequest
}
// MARK: - RequestRetrier
func should(_ manager: SessionManager, retry request: Request, with error: Error, completion: #escaping RequestRetryCompletion) {
lock.lock() ; defer { lock.unlock() }
if let response = request.task?.response as? HTTPURLResponse {
if response.statusCode == 401 {
requestsToRetry.append(completion)
if !isRefreshing {
refreshTokens { [weak self] succeeded, accessToken, refreshToken in
guard let strongSelf = self else { return }
strongSelf.lock.lock() ; defer { strongSelf.lock.unlock() }
if let accessToken = accessToken, let refreshToken = refreshToken {
strongSelf.accessToken = accessToken
strongSelf.refreshToken = refreshToken
strongSelf.updateAccessToken(accessToken: accessToken, refreshToken: refreshToken)
}
strongSelf.requestsToRetry.forEach { $0(succeeded, 0.0) }
strongSelf.requestsToRetry.removeAll()
}
}
} else {
completion(false, 0.0)
}
}
}
So, basically error handling performs in should function, not in .case(let error) in my function.

Answer 1

Ok, so there's my very stupid mistake, basically completion(false,0,0) was never executed if error occurred in should function. Everything works if it looks something like this:
// MARK: - RequestRetrier
func should(_ manager: SessionManager, retry request: Request, with error: Error, completion: #escaping RequestRetryCompletion) {
lock.lock() ; defer { lock.unlock() }
if let response = request.task?.response as? HTTPURLResponse {
if response.statusCode == 401 {
requestsToRetry.append(completion)
if !isRefreshing {
refreshTokens { [weak self] succeeded, accessToken, refreshToken in
guard let strongSelf = self else { return }
strongSelf.lock.lock() ; defer { strongSelf.lock.unlock() }
if let accessToken = accessToken, let refreshToken = refreshToken {
strongSelf.accessToken = accessToken
strongSelf.refreshToken = refreshToken
strongSelf.updateAccessToken(accessToken: accessToken, refreshToken: refreshToken)
}
strongSelf.requestsToRetry.forEach { $0(succeeded, 0.0) }
strongSelf.requestsToRetry.removeAll()
}
}
} else {
completion(false, 0.0)
} else {
completion(false,0.0)
}
}

Answer 2

You are not validating your request. Therefor it will let every request be a succes. Try validating your request by adding a validate() after the request but before the response:
self.accessSessionManager.request(...).validate().responseJSON { ... }
You can find custom ways to change the behavior what is and what is not accepted by the validate() function in their readme