Django Cheatsheet 01 — Django Basics

uv init myproject
cd myproject
uv add django

uv run django-admin startproject config .
uv run python manage.py startapp blog

myproject/
├── manage.py
├── config/
│   ├── settings.py
│   ├── urls.py
│   ├── wsgi.py
│   └── asgi.py
└── blog/
    ├── apps.py
    ├── models.py
    ├── views.py
    ├── urls.py
    ├── admin.py
    └── migrations/

INSTALLED_APPS = [
    "django.contrib.admin",
    "django.contrib.auth",
    "django.contrib.contenttypes",
    "django.contrib.sessions",
    "django.contrib.messages",
    "django.contrib.staticfiles",
    "blog",                          # your app
]

MIDDLEWARE = [
    "django.middleware.security.SecurityMiddleware",
    "django.contrib.sessions.middleware.SessionMiddleware",
    "django.middleware.common.CommonMiddleware",
    "django.middleware.csrf.CsrfViewMiddleware",
    "django.contrib.auth.middleware.AuthenticationMiddleware",
    "django.contrib.messages.middleware.MessageMiddleware",
    "django.middleware.clickjacking.XFrameOptionsMiddleware",
]

DATABASES = {
    "default": {
        "ENGINE": "django.db.backends.postgresql",
        "NAME": "myapp",
        "USER": "postgres",
        "PASSWORD": "...",
        "HOST": "localhost",
        "PORT": "5432",
    }
}

DEBUG = True
ALLOWED_HOSTS = []
ROOT_URLCONF = "config.urls"

# config/urls.py
from django.contrib import admin
from django.urls import path, include

urlpatterns = [
    path("admin/", admin.site.urls),
    path("blog/", include("blog.urls")),
]

# blog/urls.py
from django.urls import path
from . import views

app_name = "blog"

urlpatterns = [
    path("", views.post_list, name="post_list"),
    path("<int:id>/", views.post_detail, name="post_detail"),
    path("new/", views.post_create, name="post_create"),
]

path("posts/<int:id>/", views.detail, name="detail")
path("posts/<slug:slug>/", views.detail_by_slug, name="detail_by_slug")
path("posts/<int:year>/<int:month>/", views.by_month, name="by_month")

from django.urls import reverse
reverse("blog:detail", kwargs={"id": 1})       # "/posts/1/"

from django.shortcuts import render, get_object_or_404
from django.http import HttpResponse, JsonResponse

def post_list(request):
    posts = Post.objects.all()
    return render(request, "blog/list.html", {"posts": posts})

def post_detail(request, id: int):
    post = get_object_or_404(Post, id=id)
    return render(request, "blog/detail.html", {"post": post})

def api_view(request):
    return JsonResponse({"ok": True})

from django.views.generic import ListView, DetailView

class PostListView(ListView):
    model = Post
    template_name = "blog/list.html"
    context_object_name = "posts"
    paginate_by = 20

class PostDetailView(DetailView):
    model = Post
    template_name = "blog/detail.html"

# urls.py
path("", PostListView.as_view(), name="list"),

# blog/models.py
from django.db import models
from django.conf import settings

class Post(models.Model):
    title = models.CharField(max_length=200)
    slug = models.SlugField(unique=True)
    body = models.TextField()
    author = models.ForeignKey(settings.AUTH_USER_MODEL, on_delete=models.CASCADE)
    published_at = models.DateTimeField(auto_now_add=True)
    
    class Meta:
        ordering = ["-published_at"]
        indexes = [models.Index(fields=["slug"])]
    
    def __str__(self):
        return self.title

uv run python manage.py makemigrations
uv run python manage.py migrate
uv run python manage.py showmigrations

# blog/admin.py
from django.contrib import admin
from .models import Post

@admin.register(Post)
class PostAdmin(admin.ModelAdmin):
    list_display = ["title", "author", "published_at"]
    list_filter = ["published_at"]
    search_fields = ["title", "body"]
    prepopulated_fields = {"slug": ["title"]}

uv run python manage.py createsuperuser

<!-- blog/templates/blog/list.html -->
{% extends "base.html" %}

{% block content %}
<h1>Posts</h1>
<ul>
  {% for post in posts %}
    <li><a href="{% url 'blog:detail' post.id %}">{{ post.title }}</a></li>
  {% empty %}
    <li>No posts</li>
  {% endfor %}
</ul>
{% endblock %}

# settings.py
STATIC_URL = "/static/"
STATIC_ROOT = BASE_DIR / "staticfiles"      # for collectstatic in prod
STATICFILES_DIRS = [BASE_DIR / "static"]

{% load static %}
<link rel="stylesheet" href="{% static 'css/main.css' %}">

# blog/forms.py
from django import forms
from .models import Post

class PostForm(forms.ModelForm):
    class Meta:
        model = Post
        fields = ["title", "slug", "body"]

def post_create(request):
    if request.method == "POST":
        form = PostForm(request.POST)
        if form.is_valid():
            post = form.save(commit=False)
            post.author = request.user
            post.save()
            return redirect(post.get_absolute_url())
    else:
        form = PostForm()
    return render(request, "blog/form.html", {"form": form})

uv run python manage.py runserver
uv run python manage.py runserver 0.0.0.0:8000

uv run python manage.py shell

uv add --dev django-extensions ipython
uv run python manage.py shell_plus

uv run python manage.py check                # config + model checks
uv run python manage.py collectstatic        # static for prod
uv run python manage.py dbshell              # database shell
uv run python manage.py dumpdata             # serialize data
uv run python manage.py loaddata fixture.json