public void SetGroup(HttpContext context, string groupId)
        {
            if (context.Request.Payload.Length > 0)
            {
                string json  = context.Request.Payload.ReadAll();
                Group  group = JsonSerializer.DeserializeJson <Group>(json);

                int id = ApiBase.ParseId(groupId);
                if (group == null)
                {
                    throw new BadRequestException(BadRequestException.MSG_INVALID_PAYLOAD);
                }
                else
                {
                    _groupHandler.ChangeName(id, group.Name);

                    Group  response     = _groupHandler.GetGroup(id);
                    string jsonResponse = JsonSerializer.SerializeJson(response);
                    context.Response.Payload.Write(jsonResponse);
                    context.Response.Status = HttpStatus.OK;
                }
            }
            else
            {
                throw new BadRequestException(BadRequestException.MSG_PAYLOAD_EXPECTED);
            }
        }