Django Filter Package - Part-2 - The Code Learners

Django Filter Package - Part-2 - The Code Learners

In part 2 of our post on Django Filter, we’ll dive deep and learn how we can create a custom filter method and add attributes to form. To be persistent in our approach we’ll be taking the same example of part 1 of Django Filters.

In part 2 of our post on Django Filter, we’ll dive deep and learn how we can create a custom filter method and add attributes to form.

To be persistent in our approach we’ll be taking the same example of part 1 of Django Filters .

Filter queryset using a custom method

Suppose we want to display authors who have written more than a certain number of books and also display the count of books written by each author.

So for this, we have to specify a custom method that takes queryset and parameters and returns the filtered queryset of books whose author has written a certain given number of books.

We can do it the same way as shown previous part by books count is not a part of any model so we must pass method the argument to filter.

In below example, we have specified method method="author_books_count" to filter field author_books.

The method author_books_count takes 4 arguments selfquerysetnamevalue. All fields are mandatory.

  • self: refers to that filter class itself.
  • queryset : this argument has the queryset object which is currently being used for filtering. We just need to modify this queryset and return.
  • name : this has the name of the filter field in this case author_books.
  • value`: this has filtered value for that particular field.

In app(filter_and_pagination)/ file.

import django_filters
from filter_and_pagination.models import Book,Author
from django import forms

class BookFilterExp3(django_filters.FilterSet):
    book_name = django_filters.CharFilter(lookup_expr='iexact')
    author_name = django_filters.CharFilter(label="Author Name",field_name="author__author_name", lookup_expr='icontains')
    author_books = django_filters.NumberFilter(label="Number of Books Published By Author",method="author_books_count")

    class Meta:
        model = Book
        fields = ['status']

    def author_books_count(self, queryset, name, value):
        authors_qs = Author.objects.all()
        authors_id = []
        for author in authors_qs:
            count = Book.objects.filter(author=author).count()
            if count >= value:

        qs = Book.objects.filter(author__in=authors_id)                    
        return qs

Now, let’s make a view and add it to the file.

def filter_example_3(request):
    books = BookFilterExp3(request.GET)
        "books" : books
    return render(request,path,ctx)
urlpatterns = [
    path('filter_example_3', views.filter_example_3, name='filter_example_3'),

django framework python django learn python

Bootstrap 5 Complete Course with Examples

Bootstrap 5 Tutorial - Bootstrap 5 Crash Course for Beginners

Nest.JS Tutorial for Beginners

Hello Vue 3: A First Look at Vue 3 and the Composition API

Building a simple Applications with Vue 3

Deno Crash Course: Explore Deno and Create a full REST API with Deno

How to Build a Real-time Chat App with Deno and WebSockets

Convert HTML to Markdown Online

HTML entity encoder decoder Online

Python Django Tutorial | Django Course

🔥Intellipaat Django course: 👉This Python Django tutorial will help you learn what is django web development &...

Django Crud: Getting Started with Django Framework

Django: It is a python web framework. We only perform the basic create, read, update and delete operation in this example.

Learning Python: The Prompt, Then Read Template

The most Python programs will consist of three steps — getting input into the program, processing the input in some way, and outputting the results of the processing. I’m going to focus on one part of that step — getting input into a program — by prompting the user to enter some data and then reading the data into the program. This is a mostly straightforward process except for some data conversions that have to occur when you are inputting numbers.

Main Pros and Cons of Django As A Web Framework for Python Developers

India's best Institute for Django Online Training Course & Certification. Django is a high-level Python Web framework that encourages rapid development and clean, pragmatic design.

Python Tricks Every Developer Should Know

In this tutorial, you’re going to learn a variety of Python tricks that you can use to write your Python code in a more readable and efficient way like a pro.