Django is a high-level Python web framework that encourages rapid development. It includes an ORM, template engine, admin site, form handling, authentication, and security middleware out of the box.
Installation
bash
# Install Django and start a project
pip install django
django-admin startproject myproject .
python manage.py startapp core
Project Structure
# Standard Django project layout
myproject/
├── manage.py
├── myproject/
│ ├── settings.py # Configuration
│ ├── urls.py # Root URL config
│ ├── wsgi.py # WSGI entry point
│ └── asgi.py # ASGI entry point
├── core/
│ ├── models.py # Database models
│ ├── views.py # View functions/classes
│ ├── urls.py # App URL patterns
│ ├── admin.py # Admin registration
│ ├── forms.py # Form classes
│ ├── serializers.py # DRF serializers
│ ├── templates/ # HTML templates
│ └── tests.py
└── templates/ # Project-level templates
Models
python
# core/models.py — database models with Django ORM
from django.db import models
from django.contrib.auth.models import AbstractUser
class User(AbstractUser):
bio = models.TextField(blank=True)
avatar = models.ImageField(upload_to="avatars/", blank=True)
class Article(models.Model):
title = models.CharField(max_length=200)
slug = models.SlugField(unique=True)
body = models.TextField()
author = models.ForeignKey(User, on_delete=models.CASCADE, related_name="articles")
published = models.BooleanField(default=False)
created_at = models.DateTimeField(auto_now_add=True)
updated_at = models.DateTimeField(auto_now=True)
class Meta:
ordering = ["-created_at"]
def __str__(self):
return self.title
Views
python
# core/views.py — function-based and class-based views
from django.shortcuts import render, get_object_or_404, redirect
from django.views.generic import ListView, DetailView, CreateView
from django.contrib.auth.mixins import LoginRequiredMixin
from .models import Article
from .forms import ArticleForm
class ArticleListView(ListView):
model = Article
queryset = Article.objects.filter(published=True).select_related("author")
template_name = "core/article_list.html"
paginate_by = 20
class ArticleDetailView(DetailView):
model = Article
slug_field = "slug"
template_name = "core/article_detail.html"
class ArticleCreateView(LoginRequiredMixin, CreateView):
model = Article
form_class = ArticleForm
template_name = "core/article_form.html"
def form_valid(self, form):
form.instance.author = self.request.user
return super().form_valid(form)
URL Configuration
python
# core/urls.py — URL patterns for the core app
from django.urls import path
from . import views
app_name = "core"
urlpatterns = [
path("", views.ArticleListView.as_view(), name="article-list"),
path("<slug:slug>/", views.ArticleDetailView.as_view(), name="article-detail"),
path("new/", views.ArticleCreateView.as_view(), name="article-create"),
]
python
# myproject/urls.py — root URL configuration
from django.contrib import admin
from django.urls import path, include
urlpatterns = [
path("admin/", admin.site.urls),
path("articles/", include("core.urls")),
path("api/", include("core.api_urls")),
]
Admin
python
# core/admin.py — admin site registration
from django.contrib import admin
from .models import Article
@admin.register(Article)
class ArticleAdmin(admin.ModelAdmin):
list_display = ["title", "author", "published", "created_at"]
list_filter = ["published", "created_at"]
search_fields = ["title", "body"]
prepopulated_fields = {"slug": ("title",)}
raw_id_fields = ["author"]
Templates
html
<!-- templates/core/article_list.html — list view template -->
{% extends "base.html" %}
{% block content %}
<h1>Articles</h1>
{% for article in object_list %}
<article>
<h2><a href="{{ article.get_absolute_url }}">{{ article.title }}</a></h2>
<p>By {{ article.author.username }} — {{ article.created_at|date:"M d, Y" }}</p>
</article>
{% empty %}
<p>No articles yet.</p>
{% endfor %}
{% include "core/_pagination.html" %}
{% endblock %}
Django REST Framework
python
# core/serializers.py — DRF serializers
from rest_framework import serializers
from .models import Article
class ArticleSerializer(serializers.ModelSerializer):
author_name = serializers.CharField(source="author.username", read_only=True)
class Meta:
model = Article
fields = ["id", "title", "slug", "body", "author_name", "published", "created_at"]
read_only_fields = ["slug"]
python
# core/api_views.py — DRF viewsets
from rest_framework import viewsets, permissions
from .models import Article
from .serializers import ArticleSerializer
class ArticleViewSet(viewsets.ModelViewSet):
queryset = Article.objects.filter(published=True)
serializer_class = ArticleSerializer
permission_classes = [permissions.IsAuthenticatedOrReadOnly]
lookup_field = "slug"
def perform_create(self, serializer):
serializer.save(author=self.request.user)
Migrations
bash
# Create and apply database migrations
python manage.py makemigrations core
python manage.py migrate
python manage.py createsuperuser
Settings Essentials
python
# myproject/settings.py — key settings to configure
import os
from pathlib import Path
BASE_DIR = Path(__file__).resolve().parent.parent
SECRET_KEY = os.environ.get("DJANGO_SECRET_KEY", "change-me")
DEBUG = os.environ.get("DEBUG", "True") == "True"
ALLOWED_HOSTS = os.environ.get("ALLOWED_HOSTS", "localhost").split(",")
AUTH_USER_MODEL = "core.User"
DATABASES = {
"default": {
"ENGINE": "django.db.backends.postgresql",
"NAME": os.environ.get("DB_NAME", "mydb"),
"USER": os.environ.get("DB_USER", "postgres"),
"PASSWORD": os.environ.get("DB_PASSWORD", ""),
"HOST": os.environ.get("DB_HOST", "localhost"),
}
}
STATIC_URL = "/static/"
STATIC_ROOT = BASE_DIR / "staticfiles"
Testing
python
# core/tests.py — Django test example
from django.test import TestCase, Client
from django.urls import reverse
from .models import Article, User
class ArticleTests(TestCase):
def setUp(self):
self.user = User.objects.create_user(username="test", password="pass1234")
self.article = Article.objects.create(
title="Test", slug="test", body="Hello", author=self.user, published=True
)
def test_list_view(self):
resp = self.client.get(reverse("core:article-list"))
self.assertEqual(resp.status_code, 200)
self.assertContains(resp, "Test")
Running
bash
# Run development server
python manage.py runserver 0.0.0.0:8000
Key Patterns
- Use
select_relatedandprefetch_relatedto avoid N+1 queries - Set
AUTH_USER_MODELearly — it's hard to change after first migration - Use class-based views for CRUD; function views for custom logic
- Middleware order matters: SecurityMiddleware first, then SessionMiddleware
- Use
django-environoros.environfor secrets — never hardcode - Run
python manage.py check --deploybefore production deployment