Swift2.0 returning information from REST calls (Alamofire)

Question

Folks, Trying to figure out the right programmatic approach to returning data from external API calls.

Before I start and create my own quick code reuse framework (which manages all the rest api calls for my application), I would like to ask the community how they handle the following situation:

Here we have a button that is used to enter the system, we need to call our authorization service and respond to what we return.

ViewController:

import myLib

@IBAction func loginButtonTapped(sender: AnyObject) {
    let email = emailField.text!
    let password = pwField.text!
    let loginResult = myLib.login(email,password)
    if (loginResult.success) {
        NSUserDefaults.standardUserDefaults().setBool(true, forKey: "isUserLoggedIn")
        NSUserDefaults.standardUserDefaults().synchronize()
        self.dismissViewControllerAnimated(true, completion: nil)
    } else {
        displayAlertMessage(loginResult.message)
    }
}

myLib.login:

import Foundation
import Alamofire
import SwiftyJSON

public func Login(email: String, password: String, completion: ((success: Bool, message: String?, token: String?) -> Void)) {
    let parameters: [String: String] = [
        "username" : email,
        "password" : password
    ]
    let endpoint = "https://api.foo.bar/login"
    Alamofire.request(.POST, endpoint, parameters: parameters, encoding: .JSON)
        .responseJSON { response in
            guard response.result.error == nil else {
                print(response.result.error!)
                completion(success: false, message: "error calling POST on /account/login", token: nil)
                return
            }

            if let value = response.result.value {
                let apiResponseJSONBody = JSON(value)
                completion(success: true, message: nil, token: apiResponseJSONBody["token"].string)
            }
    }

}

• Is it right to pass results back as structures? I noticed that we must make the structure open in order to bring it back.

Thank! I appreciate all the feedback.

update: : Swift Alamofire + Promise

Answer 1

Login, .

, Login success = false.

, Login:

public func Login(email: String, password: String, completion: (success: Bool, message: String?, token: String?) -> Void) {
    ...
}

, Alamofire, :

completion(success: false, message: nil, token: nil)

Login :

myLib.Login(email, password) { success, message, token in
    if success {
        ...
    }
}