public async Task <IActionResult> Post([FromBody] ExerciseViewModel model) { var currentUser = await _userManager.FindByNameAsync(model.userName); var exercise = _db.Exercises.SingleOrDefault(ex => ex.name == model.exercise); var newExerciseInstance = new ExerciseInstance() { Date = model.ExerciseDate, user = currentUser, //Id = model.ExerciseInstanceId, weight = model.weight, reps = model.reps, sets = model.sets, exercise = exercise }; if (newExerciseInstance.Date == DateTime.MinValue) { newExerciseInstance.Date = DateTime.Now; } _repository.AddEntity(newExerciseInstance); _repository.SaveAll(); return(Created($"/api/ExerciseInstances/{model.ExerciseInstanceId}", model)); }