Swift - WebView HTTP Auth - Cleanest solution

Question

I have been trying to set up a web view wrapper app that will load the content of a website (still to be launched). Currently, the website is in development mode, and the only endpoints for the website are protected behind a http authentication.

I have been looking at this solution: Swift webview xcode post data

However, I do not want to make a POST request each time, but I'd rather want to authenticate against the website once and keep the connection.

What I'm looking is for a clean and stable solution, one that would allow me to be able to have control of edge cases such as bad credentials provided.

I am not comfortable with using the NSURLConnection because that solution is deprecated in iOS9. I need a solution with NSURLSession.

Let me know if I'm missing something within the above linked solution. I am sure someone had this issue as well. Additionally, the website has SSL protection.

Kind regards

Answer 1

I'm not entirely sure this fulfils your demands in the best way, but if you can use a WKWebView, maybe you can simply rely on the authentication challenge delegate method? See my answer here as well, the relevant code snippet would be:

func webView(webView: WKWebView, didReceiveAuthenticationChallenge 
           challenge: NSURLAuthenticationChallenge, 
   completionHandler: (NSURLSessionAuthChallengeDisposition, NSURLCredential?) -> Void) {

    let creds = NSURLCredential(user:"username", password:"password", persistence: NSURLCredentialPersistence.ForSession)
    completionHandler(NSURLSessionAuthChallengeDisposition.UseCredential, creds)
}

I haven't tried it yet myself, but the documentation says the credentials should be used for the session, so additional requests resulting from links should work. Even if not, that just results for the method to be called again and you can provide the credentials once more.

This is just a rump, you'd have to get name and password from an alert or the like (also you can store the credentials more elegantly to make subsequent calls to the delegate method more elegant).

You also wrote you're using SSL, so I take it you're familiar with the App Transport Security flags (since the question title just has "HTTP" in it and not "HTTPS", which you probably want for it to work smoothly, otherwise see the question I linked).

Answer 2

Okay here is the Swift 3 code.

extension MyController: WKNavigationDelegate {
    func webView(_ webView: WKWebView, didReceive challenge: URLAuthenticationChallenge, completionHandler: @escaping (URLSession.AuthChallengeDisposition, URLCredential?) -> Void) {
        guard let u = self.webuser, let p = self.webp else {
            completionHandler(.cancelAuthenticationChallenge, nil)
            return
        }

        let creds = URLCredential.init(user: u, password: p, persistence: .forSession)
        completionHandler(.useCredential, creds)
    }
}

Answer 3

You shouldn't need to use POST or a connection or session. You should just create a mutable URL request and set an auth header. Then ask the web view to load the request.

Auth header details from Wikipedia:

1. The username and password are combined with a single colon.
2. The resulting string is encoded using the RFC2045-MIME variant of Base64, except not limited to 76 char/line.
3. The authorization method and a space i.e. "Basic " is then put before the encoded string.

For example, if the user agent uses Aladdin as the username and OpenSesame as the password then the field is formed as follows:

Authorization: Basic QWxhZGRpbjpPcGVuU2VzYW1l