Flutter HTTP request fails with Connection refused error errno 111 when calling Django REST API

Backend
1

I’m working on a Flutter mobile app that connects to a Django REST framework backend. My user registration endpoint works perfectly when I test it through Postman, but I’m getting connection issues when calling it from the Flutter app.

The weird thing is that a few registrations work fine at first, but then I start getting this socket error. I’m making requests to an HTTPS URL and already tried removing CSRF protection but that didn’t help.

My Flutter code:

var payload = {
  'user_email': emailInputController.text,
  'pass1': newPasswordController.text,
  'pass2': confirmPasswordController.text,
};

// Making the HTTP call
http.post(registrationApiUrl,
    headers: requestHeaders,
    body: json.encode(payload))
.then((response) {
  print(response.body);
}).catchError((error) {
  print(error.toString());
});

Error message:

SocketException: OS Error: Connection refused, errno = 111

I should be getting back a JSON response with user details and an authentication token. Any ideas what might be causing this intermittent connection issue?

2

errno 111 means your Django server is crashing or becoming unresponsive after a few requests. This happens all the time in development when the server crashes from unhandled exceptions or memory issues. Check your Django logs right after connections start failing - you’ll see error traces or the server just stopped running. I had this exact problem when my Django views had database connection leaks that built up over multiple requests. Fix the server-side issue instead of messing with your Flutter client code. Try restarting your Django server when you get the error to confirm this is what’s happening.

3

could be a rate limiting issue on django’s side. sometimes servers block rapid requests. maybe add a wee delay or check your throttling settings. and errno 111? that just means the server’s like “nope, not gonna let you in”.

4

that’s weird - works at first then crashes? are you testing on an emulator or real device? emulators can have funky network issues. what’s your registrationApiUrl set to - localhost or a real domain?