When to use get, get_queryset, get_context_data in Django?

Question

I recently learned that you should override the get method when you specifically want to do something other than what the default view does:

class ExampleVie         


        

Answer 1

Let's look at the default implementation of ListView's get method:

https://github.com/django/django/blob/92053acbb9160862c3e743a99ed8ccff8d4f8fd6/django/views/generic/list.py#L158

class BaseListView(MultipleObjectMixin, View):
    """
    A base view for displaying a list of objects.
    """
    def get(self, request, *args, **kwargs):
        self.object_list = self.get_queryset()
        allow_empty = self.get_allow_empty()

        if not allow_empty:
            # When pagination is enabled and object_list is a queryset,
            # it's better to do a cheap query than to load the unpaginated
            # queryset in memory.
            if (self.get_paginate_by(self.object_list) is not None
                    and hasattr(self.object_list, 'exists')):
                is_empty = not self.object_list.exists()
            else:
                is_empty = len(self.object_list) == 0
            if is_empty:
                raise Http404(_("Empty list and '%(class_name)s.allow_empty' is False.")
                        % {'class_name': self.__class__.__name__})
        context = self.get_context_data()
        return self.render_to_response(context)

You will notice that get_queryset gets called in the first line. You can simply overwrite that if you just want to return your model's queryset after applying some filtering/ordering etc.

You don't need to overwrite the whole get method for that because you will be missing on all this provided functionality i.e. pagination, 404 checks etc.

get_context_data merges the resulting queryset together with context data like querystring parameters for pagination etc.

What I would recommend would be to check with django's source every once in a while and try to understand it a little bit so that you can recognize the most appropriate method you can overwrite/replace.