Getting error message with random port while making request to localhost from Flutter app

Question

** update ** Fixed it by editing my server to listen on 0.0.0.0 Getting a response now, but still, the error message wasn't right, it should've shown port 3333 not a random port. --- // ---

While trying to make a post request to http://192.168.1.1:3333, I get this error:

SocketException (SocketException: OS Error: Connection timed out, errno = 110, address = 192.168.2.9, port = 53744)

The port changes on every request but is never the right port (3333) why is that? This is my code

class Api {
  static const req_url = 'http://192.168.1.1:3333/api/auth/login';

  Future<Auth> fetchAuthToken() async {

    Map data = {
      'email': 'test@gmail.com',
      'password': '123456'
    };

    //encode Map to JSON
    var body = json.encode(data);

    var response = await http.post(req_url,
        headers: {"Content-Type": "application/json"},
        body: body
    );
    if (response.statusCode == 200) {
      // If the call to the server was successful, parse the JSON
      return Auth.fromJson(json.decode(response.body));
    } else {
      // If that call was not successful, throw an error.
      throw Exception('Failed to load post');
    }
  }
}

I've tried changing the ip to 10.0.2.2 as mentioned here but I'm not using an emulator so not sure if that even matters.

try calling this url http://192.168.1.1:3333/api/auth/login from your browser on your mobile , let us know the result. — diegoveloper, Mar 13 '19 at 18:43
Ok turned out I had to tell Adonis to listen on 0.0.0.0. Now I'm getting a response, what still confuses me is the random port thing — Karl, Mar 13 '19 at 19:45

score 1 · Answer 1 · edited May 29 '20 at 21:42

I had the same issue with my Flutter app running express.js server, but had it fixed by letting my expresss server listen on 0.0.0.0 port 3333, and within my flutter app i changed my post url to my mac IP on the network with same port 3333 http://192.168.43.210:3333/api/v02 , and boom the emulator worked

void _mypost() {

    Map<String,String> data = {
              'token':'2jmj7l5rSw0yVb/vlWAYkK/YBwk=',
              'phone':'+256750002991',
           };
    Map<String,String> headers ={
            'Content-Type': 'application/x-www-form-urlencoded'
    };
    var client = httpClient.Client();
    client.post("http://192.168.43.210:3333/api/v02", headers:headers, body:data)
    .then((response) => print(" Response Body ${response.body}"))
    .catchError((error) => print(" Response Body : ${error}"));
}

score 0 · Answer 2 · answered May 21 '20 at 17:27

i tried everything, working on emulator, android, but the same issue appeared all the time.

even tried adb reverse tcp:port tcp:port

then i used an application called ngrok which redirects to your localhost:port. still, i was getting the same error.

then, i disabled windows firewall and eureka!!!!

hope this helps someone.

Getting error message with random port while making request to localhost from Flutter app

2 Answers2