Django. How to filter posts with a date less than the current post?

Question

I'm new to programming. And I don't understand methods. On the detailview post page I want to display a list of the next posts (i.e. whose time is less than the time of the current post) How do I access the date of the current post? I try:

class PostDetailView(DetailView):
   model = Post
   slug_field = 'url'
   context_object_name = 'post'

   def get_context_data(self, **kwargs):
       context = super().get_context_data(**kwargs)
       context['earlier_posts'] = 
       Post.objects.filter(publication_date__lte=self.publication_date)
       return context

Then I have an error: 'PostDetailView' object has no attribute 'publication_date'

Thank you in advance

Answer 1

You get this error because self here refers to the PostDetailView instance, not the Post instance. You can get the model instance using DetailView.get_object()

current_post = self.get_object()
context['earlier_posts'] = self.get_queryset().filter(publication_date__lte=current_post.publication_date)