netwrok.dart

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

Future<String> getIdToken({bool? force}) async {
  // fetch update token
  return "abc*******";
}

Future<void> main() async {
  final client = http.Client();
  final token = await getIdToken();
  
  final response = await client.get(Uri.parse("https://senkyaku.jp"), headers: {
    'Authentication': 'Bearer $token'
  });
  if(response.statusCode == 401) {
    throw Exception('reacquire the token and try again');
  }
    
}