flutter - no json is sent in the body of my http post

Question

this is the code.

      Future<http.Response> postRequest () async {
        var url ='http://10.0.2.2:3000/api/message';

        Map data = {
          'message': '12345678901234567890'
        };
        //encode Map to JSON
        var body = json.encode(data);

        var response = await http.post(url,
            headers: { "accept": "application/json", "content-type": "application/json" },
            body: body
        );
        print("${response.statusCode}");
        print("${response.body}");
        return response;
      }

      postRequest();

// also tried this: headers: {"content-type":"application/json" },

In my python flask server, the post message is logging, but with empty body into it.

The flutter app is running on Android Virtual Device and the server is still running on http://0:0:0:0:3000/ and it's using request.get_json() in the method.

Using postman, everything works as expected on my server so I see the problem in the app.

postman details:

POST: http://localhost:3000/api/message

headers KEY | VALUE Content-Type | application/json

Body raw

{ "message": "opa" }

also raised here: https://github.com/flutter/flutter/issues/39351

Solution

Try passing :
Future<http.Response> postRequest () async {
        var url ='http://10.0.2.2:3000/api/message';

       Map<String, String> data = { "message": "opa" };

        var body = json.encode(data);

        var response = await http.post(url,
            headers: { "accept": "application/json", "content-type": "application/json" },
            body: body
        );
        print(response.statusCode);
        print(response.body);
        return response;
      }

      postRequest().then((response){

     print(response.body);
});

Comments

[Mohamed Elrashid]

are you using android emulator ?

[johnnnnn]

hi @MohamedElrashid, yes!

[johnnnnn]

Hi Shagun, thanks, but String data = { "message":"opa"}; is not possible. Map<String,String> can't be assgined to a variable of type 'String'.

[johnnnnn]

in my flutter app I added / in the end of url *

[Shagun Jain]

Yeah, sorry . My mistake, I have edited my code. Please take a look .