public DepartmentsController(IDepartmentDataSource departmentDataSource, ITeacherDataSource teacherDataSource)
 {
     _departmentDataSource = departmentDataSource ?? throw new ArgumentNullException(nameof(departmentDataSource));
     _teacherDataSource    = teacherDataSource ?? throw new ArgumentNullException(nameof(teacherDataSource));
 }
 public TeachersController(ITeacherDataSource teacherDataSource, WebsiteDbContext websiteDbContext)
 {
     _teacherDataSource = teacherDataSource ?? throw new ArgumentNullException(nameof(teacherDataSource));
     _websiteDbContext  = websiteDbContext ?? throw new ArgumentNullException(nameof(websiteDbContext));
 }