Back
Feb 28, 2010

Composing multiple views in Django

In UNIX way, each view should solve single task. This is good idea, but sometimes we need to mix logic of different views on same page. Filter, sort, paginate, or, for example, add comment on product page. In this article I'll show how we can mix such multiple views.

Idea

We can write views as decorators.

Example

Simplified filtration can look like this:

from django.views.generic.list_detail import object_list


def filtered_list(request, filterset_class, queryset, *args, **kwargs):
    filterset = filterset_class(request.GET)
    queryset = filterset.filter(queryset)
    kwargs['extra_context']['filterset'] = filterset

    return object_list(request, queryset, *args, **kwargs)

This is simple and straightforward, but in order to add some tricky pagination, we have to copy entire view and add more code to it.

Instead, we can create decorator like this:

def filtered(view):
    def wrapped(request, filterset_class, queryset, *args, **kwargs):
        filterset = filterset_class(request.GET)
        queryset = filterset.filter(queryset)
        kwargs['extra_context']['filterset'] = filterset
        return view(request, queryset, *args, **kwargs)

    return wrapped

Result

Assuming, that we have similar decorators, sorted и paginated, we can easily combine them:

@filtered
@paginated
def technic_list(*args, **kwargs):
    # ...

Or even like this, in lisp style:

url(r'^technic/$', filtered(sorted(paginated(object_list))), {
    'filterset_class': FilterSet,
     # ...
}, name='technic_list'),

Subscribe for the news and updates

More thoughts
Aug 18, 2022Technology
5 Best Practices of RESTful API Design to Keep Your Users Happy

Dive into our guide to RESTful API best practices

Apr 27, 2022TechnologyBusiness
How to Choose the Best Javascript Framework: Comparison of the Top Javascript Frameworks

In our article, you will find the best JavaScript framework comparison so that you know for sure how to choose the right one for your project.

May 22, 2017Technology
Web Application Security: 10 Best Practices

Protection of WEB App is of paramount importance and it should be afforded the same level of security as the intellectual rights or private property. I'm going to cover how to protect your web app.

Mar 4, 2011Technology
Css sprite generation

I've created this small sprite to create css sprites. It glues images from directory directory into single file and generates corresponding css.

Feb 18, 2010Technology
Business logic in models

In my recent project there was a lot of data business logic, so I had to organize this code somehow. In this article I'll describe a few hints on how to it.

Feb 18, 2010Technology
User profiles with inheritance in Django

Usually users' profiles are stored in single model. When there are multiple user types, separation is made by some field like user_type.Situation is a little more complicated when different data is needed for each user type.In this article I'll describe how I solve this task.