Alamofire : How to handle errors globally

Question

My question is quite similar to this one, but for Alamofire : AFNetworking: Handle error globally and repeat request

How to be able to catch globally an error (typic

Answer 1

in Alamofire 5 you can use RequestInterceptor Here is my error handling for 401 error in one of my projects, every requests that I pass the EnvironmentInterceptor to it the func of retry will be called if the request get to error and also the adapt func can help you to add default value to your requests

struct EnvironmentInterceptor: RequestInterceptor {

func adapt(_ urlRequest: URLRequest, for session: Session, completion: @escaping (AFResult) -> Void) {
    var adaptedRequest = urlRequest
    guard let token = KeychainWrapper.standard.string(forKey: KeychainsKeys.token.rawValue) else {
        completion(.success(adaptedRequest))
        return
    }
    adaptedRequest.setValue("Bearer \(token)", forHTTPHeaderField: HTTPHeaderField.authentication.rawValue)
    completion(.success(adaptedRequest))
}

func retry(_ request: Request, for session: Session, dueTo error: Error, completion: @escaping (RetryResult) -> Void) {
    if let response = request.task?.response as? HTTPURLResponse, response.statusCode == 401 {
        //get token

        guard let refreshToken = KeychainWrapper.standard.string(forKey: KeychainsKeys.refreshToken.rawValue) else {
            completion(.doNotRetryWithError(error))
            return
        }

        APIDriverAcountClient.refreshToken(refreshToken: refreshToken) { res in
            switch res {
            case .success(let response):
                let saveAccessToken: Bool = KeychainWrapper.standard.set(response.accessToken, forKey: KeychainsKeys.token.rawValue)
                let saveRefreshToken: Bool = KeychainWrapper.standard.set(response.refreshToken, forKey: KeychainsKeys.refreshToken.rawValue)
                let saveUserId: Bool = KeychainWrapper.standard.set(response.userId, forKey: KeychainsKeys.uId.rawValue)
                print("is accesstoken saved ?: \(saveAccessToken)")
                print("is refreshToken saved ?: \(saveRefreshToken)")
                print("is userID saved ?: \(saveUserId)")
                completion(.retry)
                break
            case .failure(let err):
                //TODO logout
                break

            }

        }
    } else {
        completion(.doNotRetry)
    }
}

and you can use it like this :

@discardableResult
private static func performRequest(route: ApiDriverTrip, decoder: JSONDecoder = JSONDecoder(), completion: @escaping (AFResult)->Void) -> DataRequest {

    return AF.request(route, interceptor: EnvironmentInterceptor())
        .responseDecodable (decoder: decoder){ (response: DataResponse) in
         completion(response.result)
}