Can't access jprq from Flutter

[XantaKross]

I've been developing a flutter app in Android studio for sometime now. And I created the backend using pycharm and django.

What I've done until now:

• I can access jprq site from any browser with no issues. with the url from terminal. (JPRQ works in browser)
• I can't access the same jprq site from flutter, not matter how I change the url from terminal (Tried http://, https://, name.jprq.live:80//, etc). (Changing url doesn't work.)
• Finally I tried accessing other sites from the same flutter methods (from dart pub: http.get(), dio.get()) and I can access them. Like I do get a http response. (Flutter methods do access other sites with no issues.)
• The debugger doesn't register any request when I try accessing it from flutter but it does register a request when I access it from a browser.
• The error I get in my flutter terminal is 400 Bad request.
• I've checked flutter docs there is nothing there that gives me a clue.
• I tried connecting my server in a different network and my app (which is now in my phone) in a different network. Still the same error when I request it from http.get() or dio.get()

I do not understand what all of these means it is quite frankley very very confusing.
Can someone help asap, I need to complete this project soon.

[azimjohn]

Hello @XantaKross

Interesting issue. Could you take a look at the HTTP version flutter "http" lib is using?
For a quick fix, can try using HTTP 1.1?

[XantaKross]

@azimjohn Thank you for replying so soon. It still gives me bad request.
I will add my code so that it might be helpful for you to debug.

My pubspec.yaml file (used for dependency config):

    dependencies:
      flutter:
        sdk: flutter
      cupertino_icons: ^1.0.2
      path_provider:
      cunning_document_scanner: ^1.1.2
      cookie_jar: ^4.0.8
      dio: ^5.0.0
      dio_cookie_manager: 
      http: ^1.1.0
      csv: ^5.0.0 

The dart code through which I'm trying to access the hosted server:

String Host = "https://adapt.jprq.live"; // app link declaration

class AuthSession {
  var endpoint = "$Host/SignLogIn"; // setting my specific endpoint.
  String? csrfToken;
  final dio = Dio(); 
  
  // I was actually trying to do this with dio (another library for http and https requests but powerful and complex than http), but 
  // when it failed I tried it with http in order to check if it was a problem with dio itself. Or not.
  
  final cookieJar = CookieJar();

  Map<String, dynamic> headers = {"set-cookie":null}; 


  @override
  void initState() { // this part is ignorable as it was for the dio implementation.
    dio.options.connectTimeout = 5000 as Duration?; // 5 seconds
    dio.options.receiveTimeout = 5000 as Duration?; // 5 seconds
    dio.options.followRedirects = true;
    dio.interceptors.add(CookieManager(cookieJar));
    dio.interceptors.add(LogInterceptor(requestBody: true, responseBody: true));

  }


  Future<void> getCookie() async {
    endpoint = "https://adapt.jprq.live/SignLogIn"; // manually setting up the endpoint.
    print(1);
    print(endpoint);
    print(2);
    print(headers);
    var response = (await http.get(Uri.parse(endpoint)));
    print(3);
    print(response.headers);
    print(response.body);

    // This part can also be ignored as it was for dio.
    // String setCookieHeader = '';
    // for (String header in response.headers['set-cookie']!) {
    //   if (header.startsWith('csrftoken=')) {
    //     setCookieHeader = header;
    //     break;
    //   }
    // }
    // csrfToken = setCookieHeader.split(';')[0].split('=')[1];
    // headers["Cookie"] = 'csrftoken=$csrfToken';
    // headers["X-CSRFToken"] = csrfToken;

  }

The Output:
Launching lib\main.dart on Windows in debug mode...
Building Windows application...
Nuget.exe not found, trying to download or use cached version.
√ Built build\windows\runner\Debug\gold_bucket.exe.
Debug service listening on ws://127.0.0.1:63609/a3zQLoH8z-k=/ws
Syncing files to device Windows...
flutter: 1
flutter: https://adapt.jprq.live/SignLogIn
flutter: 2
flutter: {set-cookie: null}
flutter: 3
flutter: {content-length: 11}
flutter: Bad Request

[azimjohn]

I am looking 👀

[XantaKross]

I'm sorta new to this whole thing (;テ﹏テ)

[azimjohn]

I could replicate the issue on my end. Looking closer 👀

[azimjohn]

Found the bug, fixing it

[XantaKross]

bro T_T
you're a life saver. thank you.

[azimjohn]

Fix is deployed, give it a try now

[azimjohn]

Actually the issue was on Flutter/Dart's side as mentioned here:
dart-lang/sdk#33501

Anyways jprq now works with Flutter too, thanks for reporting this issue.

If you want, consider buying me a coffee: https://buymeacoffee.com/azimjon

[XantaKross]

Oh cool.

will check out the fix rn.

Rn, I am a freelance student just trying to build my first app lol.
But I will definitely buy you an coffee when I succesfully make my first sell :)