django class-based views with inline model-form or formset

I just added my own version after checking out some of those pre-made CBVs. I specifically needed control over multiple formsets -> one parent in a single view each with individual save functions.

I basically stuffed the FormSet data binding into a get_named_formsets function which is called by get_context_data and form_valid.

There, I check if all formsets are valid, and also look for a method that overrides a plain old formset.save() on a per formset basis for custom saving.

The template renders formsets via

{% with named_formsets.my_specific_formset as formset %}
 {{ formset }}
 {{ formset.management_form }}
{% endwith %}

I think I'll be using this system regularly.

class MyView(UpdateView): # FormView, CreateView, etc
    def get_context_data(self, **kwargs):
        ctx = super(MyView, self).get_context_data(**kwargs)
        ctx['named_formsets'] = self.get_named_formsets()
        return ctx

    def get_named_formsets(self):
        return {
            'followup': FollowUpFormSet(self.request.POST or None, prefix='followup'),
            'action': ActionFormSet(self.request.POST or None, prefix='action'),
        }

    def form_valid(self, form):
        named_formsets = self.get_named_formsets()
        if not all((x.is_valid() for x in named_formsets.values())):
            return self.render_to_response(self.get_context_data(form=form))

        self.object = form.save()

        # for every formset, attempt to find a specific formset save function
        # otherwise, just save.
        for name, formset in named_formsets.items():
            formset_save_func = getattr(self, 'formset_{0}_valid'.format(name), None)
            if formset_save_func is not None:
                formset_save_func(formset)
            else:
                formset.save()
        return http.HttpResponseRedirect('')

    def formset_followup_valid(self, formset):
        """
        Hook for custom formset saving.. useful if you have multiple formsets
        """
        followups = formset.save(commit=False) # self.save_formset(formset, contact)
        for followup in followups:
            followup.who = self.request.user
            followup.contact = self.object
            followup.save()

Key points is:

  1. generated FormSets within forms.py using inlineformset_factory:

    BookImageFormSet = inlineformset_factory(BookForm, BookImage, extra=2)
    BookPageFormSet = inlineformset_factory(BookForm, BookPage, extra=5)
    
  2. returned the FormSets within a CreateView class in views.py:

    def get_context_data(self, **kwargs):
        context = super(BookCreateView, self).get_context_data(**kwargs)
        if self.request.POST:
            context['bookimage_form'] = BookImageFormSet(self.request.POST)
            context['bookpage_form'] = BookPageFormSet(self.request.POST)
        else:
            context['bookimage_form'] = BookImageFormSet()
            context['bookpage_form'] = BookPageFormSet()
        return context
    
  3. Used form_valid to save the form and formset:

     def form_valid(self, form):
         context = self.get_context_data()
         bookimage_form = context['bookimage_formset']
         bookpage_form = context['bookpage_formset']
         if bookimage_form.is_valid() and bookpage_form.is_valid():
             self.object = form.save()
             bookimage_form.instance = self.object
             bookimage_form.save()
             bookpage_form.instance = self.object
             bookpage_form.save()
             return HttpResponseRedirect('thanks/')
         else:
             return self.render_to_response(self.get_context_data(form=form))