get current user for 'created_by' field in model class

Refer official doc. It explained it pretty well. An example is also there

from django.views.generic.edit import CreateView
from myapp.models import Author

class AuthorCreate(CreateView):
    model = Author
    fields = ['name']

    def form_valid(self, form):
        form.instance.created_by = self.request.user
        return super().form_valid(form)

https://docs.djangoproject.com/en/2.1/topics/class-based-views/generic-editing/#models-and-request-user

If anyone encounters this problem I followed the advice of a_k_v and did it in views. Here is how I did it :

I added two fields in my class :

class Class(models.Model):
    created_by = models.ForeignKey(User, on_delete=models.DO_NOTHING, blank=True, null=True, related_name='create')
    updated_by = models.ForeignKey(User, on_delete=models.DO_NOTHING, blank=True, null=True, related_name='update')

then created a function :

def created_updated(model, request):
    obj = model.objects.latest('pk')
    if obj.created_by is None:
        obj.created_by = request.user
    obj.updated_by = request.user
    obj.save()

to get it into my views.py :

    if request.method == 'POST':
    form = AddVacation(request.POST)
    if form.is_valid:
        form.save()
        created_updated(Vacation, request)