Flutter http post, response body is always empty

Question

I'm struggling with http post in order to get some data from an API, but the response.body is always empty. Testing on https://reqbin.com/ works fine, so the problem is inside the code.

try {

        final response = await http.post(
          Uri.parse(
              'https://webservicesp.anaf.ro/PlatitorTvaRest/api/v8/ws/tva'),
          headers: <String, String>{
            "Access-Control-Allow-Origin":
                "*", // Required for CORS support to work
            "Access-Control-Allow-Credentials":
                'true', // Required for cookies, authorization headers with HTTPS
            "Access-Control-Allow-Headers":
                "Origin,Content-Type,X-Amz-Date,Authorization,X-Api-Key,X-Amz-Security-Token",
            "Access-Control-Allow-Methods": "GET,POST,HEAD,DELETE",
            "Cache-Control": "no-cache",
            'Content-Type': 'application/json'
          },
          body: jsonEncode({
            'cui': _identificationController.text.trim(),
            'data': DateFormat('yyyy-MM-dd').format(DateTime.now())
          }),
        );

        if (response.statusCode == 200) {
          // If the server responds successfully
          // then parse the JSON.

          print(response.body.length);
          if(response.body.isNotEmpty)
            {
              final responseData = jsonDecode(response.body);
                print(responseData);
            }
          else
            {
              print("Response body is empty\n");
            
            }

        } else {
          // If the server did not return a 200 CREATED response,
          // then throw an exception.


          throw Exception(
              'Failed to fetch company data from ANAF: ${response.statusCode}');
        }
      } catch (e) {
        print(e);
      }

While executing I've got two scenarios:

1. response code 200, response.body empty
2. response code 500 - internal error

Also I had to disable web security in chrome.dart file in order to be able to execute the http.post. Any idea how can I configure the CORS?

Answer 1

The body of the POST must be a JSON array, even if there is one JSON object.

The following code (with the outermost []s) works. If you remove the [] it fails.

import 'dart:convert';

import 'package:http/http.dart' as http;

void main() async {
  final response = await http.post(
    Uri.parse('https://webservicesp.anaf.ro/PlatitorTvaRest/api/v8/ws/tva'),
    headers: {'content-type': 'application/json'},
    body: json.encode(
      [
        {'cui': 1234, 'data': '2015-02-14'}
      ],
    ),
  );

  print(response.body);
}