iOS simulator access localhost server

Question

I am trying to get rest data to iOS app, and I use:

var rest_url = "http://192.168.0.1:8000/rest/users/"

let url: NSURL = NSURL(string: rest_url)
let session = NSURLSession.sharedSession()
let task = session.dataTaskWithURL(url, completionHandler: {data, response, error -> Void in
if(error != nil) {
    println(error.localizedDescription)
}
println(data)
var err: NSError?

var jsonResult = NSJSONSerialization.JSONObjectWithData(data, options: NSJSONReadingOptions.MutableContainers, error: &err) as NSDictionary!

But I think I can't access my server like this. Does anyone know how I can access my server from the iOS simulator?

Localhost is `127.0.0.1`. Your webserver is probably listening on that IP only. — B.R.W., Sep 06 '14 at 16:34
`The operation couldn’t be completed. (NSURLErrorDomain error -1004.) <> JSON Error The operation couldn’t be completed. (Cocoa error 3840.) fatal error: unexpectedly found nil while unwrapping an Optional value` — Mirza Delic, Sep 06 '14 at 17:06

Dmitry A. · Answer 1 · 2019-02-07T13:40:26.010

7

Do you have App Transport Security Settings in your Info.plist file? If no then for debugging purpose you can set them like

<key>NSAppTransportSecurity</key>
    <dict>
        <key>NSAllowsArbitraryLoads</key>
        <true/>
    </dict>

Such settings allow issuing requests to any server. But don't do so for a release version. It is insecure.

edited Feb 07 '19 at 13:40

answered May 02 '17 at 19:36

Dmitry A.

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score 6 · Answer 2 · answered Sep 06 '14 at 17:01

6

Make sure that your IP of your Mac is 192.168.0.1. So your url could be

var rest_url = "http://YOUR MAC IP:8000/rest/users/"

answered Sep 06 '14 at 17:01

SFeng

2,226
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16

i run python server on 192.168.0.13 with port 8000, i tryed with that url, and with 127.0.0.1:8000, but nothing works :/ `The operation couldn’t be completed. (NSURLErrorDomain error -1004.) <> JSON Error The operation couldn’t be completed. (Cocoa error 3840.) fatal error: unexpectedly found nil while unwrapping an Optional value` – Mirza Delic Sep 06 '14 at 17:06

score 4 · Answer 3 · answered Apr 15 '19 at 09:49

4

If you have a server running on the machine where you iOS simulator is running, then you need to choose 'http://127.0.0.1' as the URL.

In your case it will be :

var rest_url = "http://127.0.0.1:8000/rest/users/"

answered Apr 15 '19 at 09:49

Navid

384
2
7

score 3 · Answer 4 · answered Jul 30 '19 at 02:05

For people finding this thread because they can't connect to localhost due to an invalid certificate: in your URLSessionDelegate you should respond to the URLAuthenticationChallenge with the following delegate method:

func urlSession(_ session: URLSession, didReceive challenge: URLAuthenticationChallenge, completionHandler: @escaping (URLSession.AuthChallengeDisposition, URLCredential?) -> Void) {

    func defaultAction() { completionHandler(.performDefaultHandling, nil) }

    // Due to localhost using an invalid certificate, we need to manually accept it and move on
    guard challenge.protectionSpace.host.hasPrefix("localhost") else { return defaultAction() }
    guard challenge.protectionSpace.authenticationMethod == NSURLAuthenticationMethodServerTrust else { return defaultAction() }
    guard let trust = challenge.protectionSpace.serverTrust else { return defaultAction() }

    completionHandler(.useCredential, URLCredential(trust: trust))
}

score 1 · Answer 5 · edited Feb 01 '23 at 04:38

1

Maybe you can replace 192.168.0.1 with localhost, when debugging with iOS simulator (that is, real devices should use your server's IP).

I also cannot access my test server using IP address on simulator. But when I am using localhost or 120.0.0.1, the simulator can work well with my test server.

edited Feb 01 '23 at 04:38

Pang

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answered Aug 27 '15 at 09:35

llch

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iOS simulator access localhost server

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