5 Hidden Gems of Django Every Developer Should Know

Learn How to Use Powerful Django Features to Improve Your Code

Django is a powerful web framework that provides many features out of the box. However, there are some hidden gems that many developers may not be aware of. In this blog, we’ll explore five of these hidden gems and show you how to use them to improve your Django code.

QuerySet API

Django’s QuerySet API provides a lot of functionality for querying your database. However, many developers don’t take advantage of all of the options available to them. In this section, we’ll show you how to chain multiple filters together, use the Q object for complex queries, and use select_related() and prefetch_related() to optimize database queries.

Example 1: Chaining multiple filters together

from myapp.models import MyModel

queryset = MyModel.objects.filter(field1=value1).filter(field2=value2)

Example 2: Using the Q object for complex queries

from django.db.models import Q
from myapp.models import MyModel

queryset = MyModel.objects.filter(Q(field1=value1) | Q(field2=value2))from myapp.models import MyModel

Example 3: Using select_related() and prefetch_related() to optimize database queries

from myapp.models import MyModel

queryset = MyModel.objects.select_related('related_model').prefetch_related('related_models')

Caching

Django’s caching framework is a great way to improve the performance of your application. However, many developers don’t use it because they don’t understand how it works. In this section, we’ll show you how to cache the results of expensive database queries or other computationally expensive operations and dramatically improve the performance of your application.

from django.core.cache import cache
from myapp.models import MyModel

def get_my_data():
    my_data = cache.get('my_data')
    if my_data is None:
        my_data = MyModel.objects.all()
        cache.set('my_data', my_data)
    return my_data

Middleware

Django’s middleware system allows you to modify incoming requests and outgoing responses in a very flexible way. In this section, we’ll show you how to add or remove headers, modify cookies, or even modify the request or response objects themselves. We’ll also show you how to write your own middleware and integrate it into your application.

class MyMiddleware:
    def __init__(self, get_response):
        self.get_response = get_response

    def __call__(self, request):
        response = self.get_response(request)
        response['X-MyHeader'] = 'My Value'
        return response

Admin Site Customization

Django’s admin site is a great way to manage your application’s data, but many developers don’t realize that it can be customized to fit their specific needs. In this section, we’ll show you how to customize the look and feel of the admin site, add custom actions to the list view, and even add custom views to the admin site.

Example 1: Customizing the look and feel of the admin site

from django.contrib import admin
from myapp.models import MyModel

@admin.register(MyModel)
class MyModelAdmin(admin.ModelAdmin):
    list_display = ('field1', 'field2', 'field3')

Example 2: Adding custom actions to the list view

from django.contrib import admin
from myapp.models import MyModel

@admin.register(MyModel)
class MyModelAdmin(admin.ModelAdmin):
    list_display = ('field1', 'field2', 'field3')
    actions = ['my_custom_action']

    def my_custom_action(self, request, queryset):
        for obj in queryset:
            # Do something with the object

Example 3: Adding custom views to the admin site

from django.urls import path
from django.contrib import admin
from myapp.views import MyCustomView

urlpatterns = [
    path('my-custom-view/', MyCustomView.as_view(), name='my-custom-view'),
]

admin.site.index_template = 'admin/my_custom_index.html'

Signals

Django’s signals system allows you to execute code when certain events occur in your application. In this section, we’ll show you how to use signals to simplify your code by allowing you to move functionality out of your views and into signal handlers. We’ll also show you how to write your own signal handlers and integrate signals into your application.

from django.db.models.signals import post_save
from django.dispatch import receiver
from myapp.models import MyModel

@receiver(post_save, sender=MyModel)
def my_signal_handler(sender, instance, created, **kwargs):
    # Do something with the instance

Conclusion

By taking advantage of these hidden gems in Django, you can write more efficient, flexible, and customizable Django applications. Whether you’re a seasoned Django developer or just starting out, these features can help you take your code to the next level. So, start exploring these features today and see how they can help you improve your Django code.