flask-minify

library0.50pypypi✓ verified 86d ago

Flask extension that automatically minifies HTML, CSS, JS and Less responses using various minifiers. Current version 0.50, released April 2025. Active development, roughly quarterly releases.

web-framework http-networking

pip install flask-minify

github ↗package ↗

INSTALL

IMPORT

SIG · FLASK-MINIFY

flask-minify

web-frameworkpythonv0.50

Install

3.5s avg

Import

501ms

Disk

24MB

Pass rate

10/ 10

Env Coverage10 / 10

glibc

3.9–3.13

musl

3.9–3.13

Install & Compatibility

Where this runs

tested against v0.50 · pip install

no network on importno background threads

Install × environment matrix

Each cell = how many times install + import succeeded across repeated harness runs. Partial = flaky.
glibc = Debian/Ubuntu slim · musl = Alpine Linux

musl

py 3.10–3.915 runs

installs and imports cleanly · install 0.0s · import 0.518s · 26MB

glibc

py 3.10–3.915 runs

installs and imports cleanly · install 3.5s · import 0.484s · 27MB

24MB installed

● package 24MB

Code

Verified usage

Verified import paths — ran on the pinned version, not inferred.

Minify

✓ from flask_minify import Minify

Main class to initialize the extension.

decorators

✓ from flask_minify import minify_response

✗ from flask_minify.decorators import minify_response

In versions >=0.50, the decorator is imported directly from flask_minify. The old path may still work but is not guaranteed.

Initialize Minify with the Flask app. By default, only HTML is minified if no arguments are passed. Explicitly enable CSS/JS.

from flask import Flask from flask_minify import Minify app = Flask(__name__) Minify(app=app, html=True, css=True, js=True) @app.route('/') def index(): return '<html><body><h1>Hello</h1></body></html>' if __name__ == '__main__': app.run()

Debug

Known issues

breakingIn version 0.49, support for Python 3.7 was dropped and the dash option (--dash) was removed. Upgrade Python to 3.8+.

fix

Use Python >=3.8; remove any usage of the 'dash' parameter.

affects: >=0.49

deprecatedThe `htmlmin` backend is unmaintained; the library switched to a fork in 0.43. Using htmlmin may cause compatibility issues in the future.

fix

Use the default backend or install tdewolff-minify (pip install flask-minify[tdewolff]) for better support.

affects: >=0.43

gotchaIf you install only the base package, minification of CSS/JS may silently fail because cssmin/jsmin are optional dependencies. The extension will still serve the original content without error.

fix

Install with extras: pip install flask-minify[htmlmin] or pip install flask-minify[tdewolff] to ensure minifiers are available.

affects: all

gotchaThe `minify_response` decorator does not work on class-based views (MethodView). It only works on view functions.

fix

Use the global Minify(app=app) initialization for class-based views, or apply the decorator manually inside the method's return.

affects: all

gotchaLess compilation is only triggered if the response has a .less extension. If you serve Less files with a wrong Content-Type, it won't compile.

fix

Ensure your route returns files with .less extension, or override the Content-Type header to text/less.

affects: all

Errors

Common errors & fixes

AttributeError: module 'flask_minify' has no attribute 'Minify'

Old version (pre-0.39) used a different import pattern; or a stale cached .pyc.

fix

Upgrade to latest: pip install --upgrade flask-minify. Also clear __pycache__ if needed.

ImportError: cannot import name 'minify_response' from 'flask_minify'

The decorator was moved to the main module in 0.50. Old imports from flask_minify.decorators break.

fix

Use 'from flask_minify import minify_response' for version >=0.50.

TypeError: Minify() got an unexpected keyword argument 'dash'

The 'dash' parameter was removed in version 0.49.

fix

Remove the 'dash' argument from Minify() call. It is no longer supported.

pip install flask-minify fails with error: legacy-install-failure (or similar)

Missing build dependencies or incompatible Python version (e.g., Python 3.7 before 0.49).

fix

Upgrade Python to >=3.8; install wheel: pip install wheel; then retry.

Upgrade

Version history

0.50latest on PyPI · released Mar 29, 2025

Audit

Dependencies

FlaskrequiredCore dependency, Flask application must be present

cssminoptionalMinify CSS when using default minifiers

jsminoptionalMinify JavaScript when using default minifiers

htmlminoptionalMinify HTML when using htmlmin backend (slower but more thorough)

tdewolff-minifyoptionalAlternative fast minifier backend for HTML, CSS, JS

lesscpyoptionalCompile Less files to CSS

Agent activity

6 hits · last 30 days

node

Resources

githubhttps://github.com/mrf345/flask_minify ↗

packagehttps://pypi.org/project/flask-minify/ ↗