Future<HttpClientResponse> foo() async {
Map<String, dynamic> jsonMap = {
'homeTeam': {'team': 'Team A'},
'awayTeam': {'team': 'Team B'},
};
String jsonString = json.encode(jsonMap); // encode map to json
String paramName = 'param'; // give the post param a name
String formBody = paramName + '=' + Uri.encodeQueryComponent(jsonString);
List<int> bodyBytes = utf8.encode(formBody); // utf8 encode
HttpClientRequest request =
await _httpClient.post(_host, _port, '/a/b/c');
// it's polite to send the body length to the server
request.headers.set('Content-Length', bodyBytes.length.toString());
// todo add other headers here
request.add(bodyBytes);
return await request.close();
}