Django code explainers

python

import time
import uuid
 
from django.utils.deprecation import MiddlewareMixin

Attaching per-request context in Django

middleware request lifecycle multi-tenancy

Intermediate 7 steps

python

import secrets
 
from django.contrib.auth import authenticate, login
from django.core.cache import cache

Two-factor login with OTP in Django

two-factor-auth one-time-passwords caching

Intermediate 9 steps

python

from django.db import connections
from django.db.utils import OperationalError
from django.core.cache import caches
from django.http import JsonResponse

Building a health check endpoint in Django

health check monitoring database

Intermediate 7 steps

python

from django.db import models
from django.db.models import F, Sum, DecimalField
from django.db.models.functions import Coalesce

Recomputing order totals in Django

annotations aggregation custom-manager

Intermediate 9 steps

python

from django import forms
from django.contrib.auth import get_user_model
from django.shortcuts import redirect
from formtools.wizard.views import SessionWizardView

Building a multi-step form with Django wizards

form-wizard multi-step-forms session-state

Intermediate 8 steps

python

from celery import shared_task, signature
from django.core.mail import send_mail
 
from .models import Report, ReportExport

Chaining Celery tasks in Django

asynchronous tasks task chaining retries

Intermediate 8 steps

python

from django.db import models
 
 
class Order(models.Model):

Tracking field changes in a Django model

change-tracking audit-log model-lifecycle

Intermediate 8 steps

python

from django.db import transaction
from django.db.models import F
from django.http import JsonResponse
from django.views.decorators.http import require_POST

Safely reordering tasks with a Django action

transactions row-locking validation

Advanced 8 steps

python

from django.core.cache import cache
from django.core.cache.utils import make_template_fragment_key
from django.db.models.signals import post_save, post_delete
from django.dispatch import receiver

Busting template fragment caches in Django

caching signals cache-invalidation

Intermediate 4 steps

python

from django.urls import path, include
 
app_name = "api"

How URL-namespaced API versioning works in Django

api versioning url routing namespaces

Intermediate 8 steps

python

from django import forms
from django.utils import timezone
 
from .models import Reservation

Multi-field validation in a Django ModelForm

form validation cross-field validation modelform

Intermediate 7 steps

python

from django import template
from django.urls import reverse, NoReverseMatch
from django.utils.html import format_html

Active nav-link template tags in Django

template tags url routing active state

Intermediate 7 steps

python

import os
from pathlib import Path
 
BASE_DIR = Path(__file__).resolve().parent.parent.parent

How a Django settings module is wired

configuration environment-variables middleware

Intermediate 8 steps

python

from django.db.models import Q
 
from .models import Order

DISTINCT ON queries in Django

orm querysets postgresql

Intermediate 7 steps

python

from decimal import Decimal, ROUND_HALF_UP
 
from django.db import transaction
from django.db.models import F

Batch price updates safely in Django

decimal-precision batch-processing transactions

Advanced 8 steps

python

from django.db import transaction
from django.forms import inlineformset_factory
from django.shortcuts import get_object_or_404, redirect, render

Editing an order with inline formsets in Django

formsets transactions crud

Intermediate 9 steps

python

from django.core.paginator import Paginator
from django.shortcuts import render
 
from .models import Product

Filtering and paginating a Django product list

queryset pagination filtering

Intermediate 7 steps

python

from pathlib import Path
 
from django.contrib.auth.decorators import login_required
from django.http import FileResponse, Http404, HttpResponseForbidden

Serving files with access checks in Django

authorization http-caching file-serving

Intermediate 7 steps