public async Task <IActionResult> GetAll([FromQuery] string teacher)
{
if (teacher != null)
{
var result = await _subjectsRepository.ReadMatchingStudent(subject => subject.Teacher == teacher);
return(Ok(result));
}
var allEntities = await _subjectsRepository.ReadAll();
if (allEntities != null)
{
return(Ok(allEntities));
}
return(HttpNotFound());
}