django-prettify-html

Use markup_fmt, the extremely fast HTML formatter, with Django.

Provides a Django middleware that automatically prettifies HTML responses for readable "View Source" output during development — the counterpart to django-minify-html for production.

Powered by Rust via PyO3 — no subprocess overhead, no Node.js dependency.

Requirements

• Python 3.10 to 3.14
• Django 4.2 to 6.0

Installation

pip install django-prettify-html

Setup

1. Add to your INSTALLED_APPS:

INSTALLED_APPS = [
    ...,
    "django_prettify_html",
    ...,
]

2. Add the middleware (typically last, or in place of a minification middleware):

MIDDLEWARE = [
    ...,
    "django_prettify_html.middleware.PrettifyHtmlMiddleware",
]

Usage

The middleware prettifies all non-streaming, non-encoded HTML responses.

Customizing options

Subclass the middleware and override format_args:

from django_prettify_html.middleware import PrettifyHtmlMiddleware

class ProjectPrettifyHtmlMiddleware(PrettifyHtmlMiddleware):
    format_args = PrettifyHtmlMiddleware.format_args | {
        "indent_width": 4,
        "print_width": 100,
    }

Skipping specific views

from django_prettify_html.decorators import no_html_prettification

@no_html_prettification
def raw_view(request):
    return HttpResponse("<pre>unformatted</pre>")

Using the formatter directly

from django_prettify_html import format

html = "<div><p>Hello</p></div>"
pretty = format(html, indent_width=2, print_width=80)

Available options

Option	Type	Default	Description
language	str	"html"	Language: html, jinja, vue, svelte, astro, angular, vento, mustache, xml
print_width	int	80	Maximum line width before wrapping
indent_width	int	2	Number of spaces per indent level
use_tabs	bool	False	Use tabs instead of spaces
line_break	str	"lf"	Line break style: "lf" or "crlf"
quotes	str	"double"	Attribute quote style: "double" or "single"
format_comments	bool	False	Format HTML comments
closing_bracket_same_line	bool	False	Keep closing bracket on same line as last attribute
max_attrs_per_line	int|None	None	Maximum attributes per line (None = unlimited)
prefer_attrs_single_line	bool	False	Prefer all attributes on a single line when possible
html_normal_self_closing	bool|None	None	Self-close normal HTML elements
html_void_self_closing	bool|None	None	Self-close void elements (br, img, etc.)
whitespace_sensitivity	str	"css"	Whitespace handling: "css", "strict", or "ignore"
doctype_keyword_case	str	"ignore"	DOCTYPE keyword case: "ignore", "upper", or "lower"

Recommended setup: minify in production, prettify in development

# settings/base.py
MIDDLEWARE = [
    ...,
    "myapp.middleware.MinifyMiddleware",  # production minification
]

# settings/development.py
MIDDLEWARE = [
    "django_prettify_html.middleware.PrettifyHtmlMiddleware" if m == "myapp.middleware.MinifyMiddleware" else m
    for m in MIDDLEWARE
]

Acknowledgments

This project draws inspiration from:

• django-minify-html — the production counterpart that proved the "fast Rust library + Django middleware" pattern works well
• markup_fmt — the formatter that powers this project
• djangofmt — a Django template formatter that also builds on markup_fmt

Releasing

Version is defined in one place: Cargo.toml. Both pyproject.toml and __init__.__version__ read from it automatically.

To release a new version:

# 1. Bump version in Cargo.toml
# 2. Commit, tag, and push
git commit -am "v0.2.0"
git tag v0.2.0
git push origin main --tags

The GitHub Actions release workflow handles the rest:

• Builds wheels for Linux (x86/arm64), macOS (x86/arm64), Windows (x86)
• Builds for Python 3.10, 3.11, 3.12, 3.13, 3.14
• Publishes to PyPI via trusted publishing
• Creates a GitHub Release with auto-generated notes and wheel artifacts

License

MIT