public async Task <IActionResult> ForDepartment([FromQuery] string departmentId, [FromQuery] string roomNumber, CancellationToken token) { var query = new EmployeesQuery(); if (!string.IsNullOrWhiteSpace(departmentId)) { query = query.ForDepartment(departmentId); } if (!string.IsNullOrWhiteSpace(roomNumber)) { query = query.ForRoom(roomNumber); } var employees = await this.LoadEmployeesAsync(query, token); return(this.Ok(employees)); }