Django多模型最佳实践

Question

Basically what I'm trying to achieve is a multi-model django app where different models take advantage of the same views. For example I've got the models 'Car' 'Make' 'Model' etc and I want to build a single view to perform the same task for each, such as add, delete and edit, so I don't have to create a seperate view for add car, ass make etc. I've built a ModelForm and Model object for each and would want to create a blank object when adding and a pre-populated form object when editing (through the form instance arg), with objects being determined via url parameters.

Where I'm stuck is that I'm not sure what the best way to so this is. At the moment I'm using a load of if statements to return the desired object or form based on parameters I'm giving it, which get's a bit tricky when different forms need specifying and whether they need an instance or not. Although this seems to be far from the most efficient way of achieving this.

Django seems to have functions to cover most repetitive tasks, is there some magic I'm missing here?

edit - Here's an example of what I'm doing with the arguments I'm passing into the url:

def edit_object(request, object, id):
    if(object==car):
        form = carForm(instance = Car.objects.get(pk=id)
    return render(request, 'template.html', {'form':form})

Answer 1

What about using Class Based Views ? Using CBVs is the best way in Django to make reusable code. For this example maybe it can be a little longer than function based views, but when the project grows up it makes the difference. Also remember "Explicit is better than implicit".

urls.py

# Edit
url(r'^car/edit/(?P<pk>\d+)/$', EditCar.as_view(), name='edit-car'),
url(r'^make/edit/(?P<pk>\d+)/$', EditMake.as_view(), name='edit-make'),

# Delete
url(r'^car/delete/(?P<pk>\d+)/$', DeleteCar.as_view(), name='delete-car'),
url(r'^make/delete/(?P<pk>\d+)/$', DeleteMake.as_view(), name='delete-make'),

views.py

class EditSomethingMixin(object):
    """Use Mixins to reuse common behavior"""
    template_name = 'template-edit.html'


class EditCar(EditSomethingMixin, UpdateView):
    model = Car
    form_class = CarForm


class EditMake(EditSomethingMixin, UpdateView):
    model = Make
    form_class = MakeForm


class DeleteSomethingMixin(object):
    """Use Mixins to reuse common behavior"""
    template_name = 'template-delete.html'


class DeleteCar(DeleteSomethingMixin, DeleteView):
    model = Car


class DeleteMake(DeleteSomethingMixin, DeleteView):
    model = Make

Answer 2

Just pass your class and form as args to the method then call them in the code.

def edit_object(request, model_cls, model_form, id):
    form = model_form(instance = model_cls.objects.get(pk=id)
    return render(request, 'template.html', {'form':form})

then just pass in the correct classes and forms in your view methods

def edit_car(request,id):
    return edit_object(request, Car, CarForm, id)

each method knows what classes to pass, so you eliminate the if statements.

Answer 3

urls.py

url(r'^car/delete/(?<pk>\d+)/', edit, {'model': Car})
url(r'^make/delete/(?<pk>\d+)/', edit, {'model': Make})

views.py

def edit(request, id, model):
    model.objects.get(id=id).delete()