Using mixins in class based view - Django

Question

So I started using the generic class based views and I gotta say, they do save time. But I was wondering whether I could use mixins to provide generic impl rather than having to code in each view. for e.g. I have a ListView and DetailView. To restrict the listing and editing, I could override the get_queryset() and filter it by the logged in user. But as you guessed, i would have to do that in each view,

class JediListView(ListView):
    def get_queryset(self):
        q = <call super>.filter(user=request.user) #assume i have 'login_required' in the urls

class JediDetailView(DetailView):
    def get_queryset(self):
        q = <call super>.filter(user=request.user) #assume i have 'login_required' in the urls

I could create a new parent class for each of the view but I would still be repeating the code.

class RepublicListView(ListView):
     # override get_queryset code as above

class JediListView(RepublicListView):

# repeat fot DetailView, DeleteView, UpdateView

I was wondering about mixins, I am exactly sure how mixins work [from java background, so I am awed and fearful at the same time]

Answer 1

You actually almost found the answer by yourself. You can write the following Mixin:

class UserFilterMixin:
    def get_queryset(self):
        return <call super>.filter(user=self.request.user)

And then use it in the classes like this:

class RepublicListView(LoginRequiredMixin, UserFilterMixin, ListView):

And so on for the other classes...

Answer 2

You can use LoginRequiredMixin from django-braces.

from django.views.generic import ListView, DetailView

from braces.views import LoginRequiredMixin


class JediListView(LoginRequiredMixin, ListView):
    model = JediModel


class JediDetailView(LoginRequiredMixin, Detail):
    model = JediModel

As per Chapter-8: Best Practices for Class-Based Views from TWO SCOOPS of DJANGO,

THIRD-PARTY PACKAGES: CBVs + django-braces Are Great Together We feel that django-braces is the missing component for Django CBVs. It provides a set of clearly coded mixins that make Django CBVs much easier and faster to implement. !e next few chapter will demonstrate it's mixins in various code examples.