---
name: "libsass"
section: "3"
platform: "linux"
package: "python3-libsass"
version: "0.23.0-0.1"
release: "Debian 13 (Trixie)"
platforms: ["linux"]
url: "https://new.carta.tech/libsass/3"
---
# libsass(3)
libsass Documentation This package provides a simple Python extension module sass which is binding LibSass (written in C/C++ by Hampton Catlin and Aaron Leung). It's very straightforward and there isn't any headache related to Python distribution/deployment. That means you can add just libsass into your setup.py's install\_requires list or requirements.txt file. It currently supports CPython 3.7+ and PyPy 3!
## NAME
libsass - libsass Documentation
This package provides a simple Python extension module *sass* which is binding *LibSass* (written in C/C++ by Hampton Catlin and Aaron Leung). It's very straightforward and there isn't any headache related to Python distribution/deployment. That means you can add just **libsass** into your **setup.py**'s **install\_requires** list or **requirements.txt** file.
It currently supports CPython 3.7+ and PyPy 3!
## FEATURES
- •
You don't need any Ruby/Node.js stack at all, for development or deployment either.
- •
Fast. (*LibSass* is written in C++.)
- •
Simple API. See *example code* for details.
- •
Custom functions.
- •
**@import** callbacks.
- •
Support both tabbed (Sass) and braces (SCSS) syntax.
- •
WSGI middleware for ease of development. It automatically compiles Sass/SCSS files for each request. See also *sassutils.wsgi* for details.
- •
**setuptools**/**distutils** integration. You can build all Sass/SCSS files using **setup.py build\_sass** command. See also *sassutils.distutils* for details.
- •
Works also on PyPy.
- •
Provides prebuilt wheel (*PEP 427*) binaries for Windows and Mac.
## INSTALL
It's available on *PyPI*, so you can install it using **pip**:
```
$ pip install libsass
```
**NOTE:**
libsass requires some features introduced by the recent C++ standard. You need a C++ compiler that support those features. See also libsass project's *README* file.
## EXAMPLES
### Compile a String of Sass to CSS
```
>>> import sass
>>> sass.compile(string='a { b { color: blue; } }')
'a b {\n color: blue; }\n'
```
### Compile a Directory of Sass Files to CSS
```
>>> import sass
>>> import os
>>> os.mkdir('css')
>>> os.mkdir('sass')
>>> scss = """\
... $theme_color: #cc0000;
... body {
... background-color: $theme_color;
... }
... """
>>> with open('sass/example.scss', 'w') as example_scss:
... example_scss.write(scss)
...
>>> sass.compile(dirname=('sass', 'css'), output_style='compressed')
>>> with open('css/example.css') as example_css:
... print(example_css.read())
...
body{background-color:#c00}
```
## USER'S GUIDE
### Using with Flask
This guide explains how to use libsass with the *Flask* web framework. *sassutils* package provides several tools that can be integrated into web applications written in Flask.
### Contents
- •
*Using with Flask*
- •
*Directory layout*
- •
*Defining manifest*
- •
*Building Sass/SCSS for each request*
- •
*Building Sass/SCSS for each deployment*
### Directory layout
Imagine the project contained in such directory layout:
- •
**setup.py**
- •
**myapp/**
- •
**\_\_init\_\_.py**
- •
**static/**
- •
**sass/**
- •
**css/**
- •
**templates/**
Sass/SCSS files will go inside **myapp/static/sass/** directory. Compiled CSS files will go inside **myapp/static/css/** directory. CSS files can be regenerated, so add **myapp/static/css/** into your ignore list like **.gitignore** or **.hgignore**.
### Defining manifest
The *sassutils* defines a concept named *manifest*. Manifest is the build settings of Sass/SCSS. It specifies some paths related to building Sass/SCSS:
- •
The path of the directory which contains Sass/SCSS source files.
- •
The path of the directory which the compiled CSS files will go.
- •
The path, exposed to HTTP (through WSGI), of the directory that will contain the compiled CSS files.
Every package may have its own manifest. Paths have to be relative to the path of the package.
For example, in the above project, the package name is **myapp**. The path of the package is **myapp/**. The path of the Sass/SCSS directory is **static/sass/** (relative to the package directory). The path of the CSS directory is **static/css/**. The exposed path is **/static/css**.
These settings can be represented as the following manifests:
```
{
'myapp': ('static/sass', 'static/css', '/static/css')
}
```
As you can see the above, the set of manifests are represented in dictionary, in which the keys are packages names and the values are tuples of paths.
### Building Sass/SCSS for each request
**SEE ALSO:**
- **Flask --- *Hooking in WSGI Middlewares***
The section which explains how to integrate WSGI middlewares to Flask.
- **Flask --- flask:app-dispatch**
The documentation which explains how Flask dispatches each request internally.
In development, manually building Sass/SCSS files for each change is a tedious task. *SassMiddleware* makes the web application build Sass/SCSS files for each request automatically. It's a WSGI middleware, so it can be plugged into the web app written in Flask.
*SassMiddleware* takes two required parameters:
- •
The WSGI-compliant callable object.
- •
The set of manifests represented as a dictionary.
So:
```
from flask import Flask
from sassutils.wsgi import SassMiddleware
app = Flask(__name__)
app.wsgi_app = SassMiddleware(app.wsgi_app, {
'myapp': ('static/sass', 'static/css', '/static/css')
})
```
And then, if you want to link a compiled CSS file, use the *url\_for()* function:
```
```
**NOTE:**
The linked filename is **style.scss.css**, not just **style.scss**. All compiled filenames have trailing **.css** suffix.
### Building Sass/SCSS for each deployment
**NOTE:**
This section assumes that you use *setuptools* for deployment.
**SEE ALSO:**
- **Flask --- flask:distribute-deployment**
How to deploy Flask application using *setuptools*.
If libsass is installed in the **site-packages** (for example, your virtualenv), the **setup.py** script also gets a new command provided by libsass: *build\_sass*. The command is aware of the **sass\_manifests** option of **setup.py** and builds all Sass/SCSS sources according to the manifests.
Add these arguments to **setup.py** script:
```
setup(
# ...,
setup_requires=['libsass >= 0.6.0'],
sass_manifests={
'myapp': ('static/sass', 'static/css', '/static/css')
}
)
```
The **setup\_requires** option makes sure that libsass is installed in **site-packages** (for example, your virtualenv) before the **setup.py** script. That means if you run the **setup.py** script and libsass isn't installed in advance, it will automatically install libsass first.
The **sass\_manifests** specifies the manifests for libsass.
Now **setup.py build\_sass** will compile all Sass/SCSS files in the specified path and generates compiled CSS files inside the specified path (according to the manifests).
If you use it with **sdist** or **bdist** commands, the packed archive will also contain the compiled CSS files!
```
$ python setup.py build_sass sdist
```
You can add aliases to make these commands always run the **build\_sass** command first. Make **setup.cfg** config:
```
[aliases]
sdist = build_sass sdist
bdist = build_sass bdist
```
Now it automatically builds Sass/SCSS sources and include the compiled CSS files to the package archive when you run **setup.py sdist**.
### Changelog
### Version 0.23.0
Released on January 6, 2024.
- •
Follow up the libsass upstream: 3.6.6 --- See the release notes of LibSass *3.6.6*. \[*452* by Anthony Sottile\]
### Version 0.22.0
Released on November 12, 2022.
- •
Remove python 2.x support \[*373* by anthony sottile\].
- •
Remove deprecated **sassc** cli \[*379* by anthony sottile\].
### Version 0.21.0
Released on May 20, 2021.
- •
Fix build on OpenBSD. \[*310* by Denis Fondras\].
- •
Produce abi3 wheels on windows. \[*322* by Anthony Sottile\]
- •
Make the manpage build reproducible. \[*319* by Chris Lamb\]
- •
Follow up the libsass upstream: 3.6.5 --- See the release notes of LibSass *3.6.5*. \[*344* by Anthony Sottile\]
### Version 0.20.1
Released on August 27, 2020.
- •
(no changes, re-releasing to test build automation)
### Version 0.20.0
Released on May 1, 2020.
- •
Produce abi3 wheels on macos / linux \[*307* by Anthony Sottile\]
- •
Follow up the libsass upstream: 3.6.4 --- See the release notes of LibSass *3.6.4*. \[*313* by Anthony Sottile\]
### Version 0.19.4
Released on November 3, 2019.
- •
Follow up the libsass upstream: 3.6.3 --- See the release notes of LibSass *3.6.3*. \[*304* by Anthony Sottile\]
### Version 0.19.3
Released on October 5, 2019.
- •
Follow up the libsass upstream: 3.6.2 --- See the release notes of LibSass *3.6.2*. \[*302* by Anthony Sottile\]
### Version 0.19.2
Released on June 16, 2019.
- •
Follow up the libsass upstream: 3.6.1 --- See the release notes of LibSass *3.6.1*. \[*298* by Anthony Sottile\]
### Version 0.19.1
Released on May 18, 2019.
- •
Re-release of 0.19.0 with windows python2.7 wheels \[*297* by Anthony Sottile\]
### Version 0.19.0
Released on May 18, 2019.
- •
Follow up the libsass upstream: 3.6.0 --- See the release notes of LibSass *3.6.0*. \[*295* by Anthony Sottile\]
### Version 0.18.0
Release on March 13, 2019
- •
Add support for previous import path to importer callbacks \[*287* *291* by Frankie Dintino\]
### Version 0.17.0
Release on January 03, 2019
- •
- **Add several new cli options \[*279* *268* by Frankie Dintino\]**
- •
**--sourcemap-file**: output file for source map
- •
**--sourcemap-contents**: embed **sourcesContent** in source map
- •
**--sourcemap-embed**: embed **sourceMappingURL** as data uri
- •
**--omit-sourcemap-url**: omit source map url comment from output
- •
**--sourcemap-root**: base path, emitted as **sourceRoot** in source map
- •
Fix **.sass** in **WsgiMiddleware** (again) \[*280* by Anthony Sottile\]
### Version 0.16.1
Released on November 25, 2018.
- •
Fix compilation on macos mojave \[*276* *277* by Anthony Sottile\]
- •
Fix **.sass** in **WsgiMiddleware** for **strip\_extension=True** \[*278* by Anthony Sottile\]
### Version 0.16.0
Released on November 13, 2018.
- •
Use **-lc++** link flag when compiling with **clang** \[*270* by Christian Thieme *271* by Anthony Sottile\]
- •
Honor **strip\_extension** in **SassMiddleware** \[*274* by Anthony Sottile\]
- •
Follow up the libsass upstream: 3.5.5 --- See the release notes of LibSass *3.5.5*. \[*275* by Anthony Sottile\]
### Version 0.15.1
Released on September 24, 2018.
- •
Fix **setup.py sdist** (regressed in 0.15.0) \[*267* by Anthony Sottile\]
### Version 0.15.0
Released on September 16, 2018.
- •
Fix invalid escape sequences \[*249* by Anthony Sottile\]
- •
Add code of conduct \[*251* by Nick Schonning\]
- •
Add support for python3.7 and remove testing for python3.4 \[*254* by Anthony Sottile\]
- •
Add **strip\_extension** option for wsgi / distutils builder \[*55* *258* by Anthony Sottile *260* by Morten Brekkevold\]
- •
Deprecate **sassc** (replaced by **pysassc**). \[*262* by Anthony Sottile\]
- •
Import abc classes from **collections.abc** to remove **DeprecationWarning** \[*264* by Gary van der Merwe *265* by Anthony Sottile\]
### Version 0.14.5
Released on April 25, 2018.
- •
Follow up the libsass upstream: 3.5.4 --- See the release notes of LibSass *3.5.4*. \[*247* by Anthony Sottile\]
### Version 0.14.4
Released on April 24, 2018.
- •
Add ability to specify imports for custom extensions. This provides a way to enable imports of **.css** files (which was removed in 3.5.3). Specify **--import-extensions .css** to restore the previous behavior. \[*246* by Samuel Colvin\]
### Version 0.14.3
Released on April 23, 2018.
- •
Follow up the libsass upstream: 3.5.3 --- See the release notes of LibSass *3.5.3*. \[*244* by Anthony Sottile\]
### Version 0.14.2
Released on March 16, 2018.
- •
Follow up the libsass upstream: 3.5.2 --- See the release notes of LibSass *3.5.2*. \[*243* by Anthony Sottile\]
### Version 0.14.1
Released on March 12, 2018.
- •
Follow up the libsass upstream: 3.5.1 --- See the release notes of LibSass *3.5.1*. \[*242* by Anthony Sottile\]
### Version 0.14.0
Released on March 6, 2018.
- •
Follow up the libsass upstream: 3.5.0 --- See the release notes of LibSass *3.5.0*. \[*241* by Anthony Sottile\]
- •
**SassList** type gained an additional option **bracketed=False** to match the upstream changes to the **sass\_list** type. \[*184* by Anthony Sottile\]
### Version 0.13.7
Released on February 5, 2018.
- •
Follow up the libsass upstream: 3.4.9 --- See the release notes of LibSass *3.4.9*. \[*232* by Anthony Sottile\]
### Version 0.13.6
Released on January 19, 2018.
- •
libsass-python has moved to the sass organization!
### Version 0.13.5
Released on January 11, 2018.
- •
Follow up the libsass upstream: 3.4.8 --- See the release notes of LibSass *3.4.8*. \[*228* by Anthony Sottile\]
### Version 0.13.4
Released on November 14, 2017.
- •
Follow up the libsass upstream: 3.4.7 --- See the release notes of LibSass *3.4.7*. \[*226* by Anthony Sottile\]
### Version 0.13.3
Released on October 11, 2017.
- •
Sort input files for determinism \[*212* by Bernhard M. Wiedemann\]
- •
Include LICENSE file in distributions \[*216* by Dougal J. Sutherland\]
- •
Add a **pysassc** entry to replace **sassc** \[*218* by Anthony Sottile\]
- •
Enable building with dynamic linking \[*219* by Marcel Plch\]
- •
Follow up the libsass upstream: 3.4.6 --- See the release notes of LibSass *3.4.6*. \[*221* by Anthony Sottile\]
### Version 0.13.2
Released on June 14, 2017.
- •
Always add cwd to import paths \[*208* by Anthony Sottile\]
### Version 0.13.1
Released on June 8, 2017.
- •
Follow up the libsass upstream: 3.4.5 --- See the release notes of LibSass *3.4.5*. \[*207* by Anthony Sottile\]
### Version 0.13.0
Released on June 7, 2017.
- •
Use **getfullargspec** when available in python 3. \[*188* by Thom Wiggers\]
- •
Use **sass\_copy\_c\_string** instead of **strdup** for portability \[*196* by Anthony Sottile\]
- •
Use **-std=gnu++0x** to fix installation under cygwin \[*195* *197* by Anthony Sottile\]
- •
Correct source map url \[*201* *202* by Anthony Sottile\]
- •
Remove **--watch** \[*203* by Anthony Sottile\]
- •
Follow up the libsass upstream: 3.4.4 --- See the release notes of LibSass *3.4.4*. \[*205* by Anthony Sottile\]
### Version 0.12.3
Released on January 7, 2017.
- •
Follow up the libsass upstream: 3.4.3 --- See the release notes of LibSass *3.4.3*. \[*178* by Anthony Sottile\]
### Version 0.12.2
Released on January 5, 2017.
- •
Follow up the libsass upstream: 3.4.2 --- See the release notes of LibSass *3.4.2*. \[*176* by Anthony Sottile\]
### Version 0.12.1
Released on December 20, 2016.
- •
Follow up the libsass upstream: 3.4.1 --- See the release notes of LibSass *3.4.1*. \[*175* by Anthony Sottile\]
### Version 0.12.0
Released on December 10, 2016.
- •
Follow up the libsass upstream: 3.4.0 --- See the release notes of LibSass *3.4.0*. \[*173* by Anthony Sottile\]
### Version 0.11.2
Released on October 24, 2016.
- •
Drop support for python2.6 \[*158* by Anthony Sottile\]
- •
Deprecate **--watch** \[*156* by Anthony Sottile\]
- •
Preserve line endings \[*160* by Anthony Sottile\]
- •
Follow up the libsass upstream: 3.3.6 --- See the release notes of LibSass *3.3.6*. \[*167* by Anthony Sottile\]
### Version 0.11.1
Released on April 22, 2016.
- •
Follow up the libsass upstream: 3.3.5 --- See the release notes of LibSass *3.3.5*. \[*148* by Anthony Sottile\]
### Version 0.11.0
Released on March 23, 2016.
- •
Follow up the libsass upstream: 3.3.4 --- See the release notes of LibSass *3.3.4*. \[*144* by Anthony Sottile\]
- •
Expose libsass version in **sassc --version** and **sass.libsass\_version** \[*142* *141* *140* by Anthony Sottile\]
- •
Fix warning about unused enum on switch \[*127* *131* by Anthony Sottile\]
- •
Sourcemaps no longer imply source comments \[*124* *130* by Tim Tisdall\]
- •
Add **--source-comments** option to **sassc** \[*124* *130* by Anthony Sottile\]
- •
Improve formatting of **CompileError** under python3 \[*123* by Anthony Sottile\]
- •
Raise when compiling a directory which does not exist \[*116* *119* by Anthony Sottile\]
### Version 0.10.1
Released on January 29, 2016.
- •
Follow up the libsass upstream: 3.3.3 --- See the release notes of LibSass *3.3.3*. \[by Anthony Sottile\]
- •
Allow -t for style like sassc \[*98* by Anthony Sottile\]
### Version 0.10.0
Released on December 15, 2015.
- •
Support custom import callbacks \[*81* by Alice Zoë Bevan–McGregor, Anthony Sottile\]
- •
Disallow arbitrary kwargs in compile() \[*109* by Anthony Sottile\]
### Version 0.9.3
Released on December 03, 2015.
- •
Support "indented" Sass compilation \[*41* by Alice Zoë Bevan–McGregor\]
- •
Fix wheels on windows \[*28* *49* by Anthony Sottile\]
### Version 0.9.2
Released on November 12, 2015.
- •
Follow up the libsass upstream: 3.3.2 --- See the release notes of LibSass *3.3.2*. \[by Anthony Sottile\]
- •
Require VS 2015 to build on windows \[*99* by Anthony Sottile\]
### Version 0.9.1
Released on October 29, 2015.
- •
Follow up the libsass upstream: 3.3.1 --- See the release notes of LibSass *3.3.1*. \[by Anthony Sottile\]
### Version 0.9.0
Released on October 28, 2015.
- •
Fix a bug with writing UTF-8 to a file \[*72* by Caleb Ely\]
- •
Fix a segmentation fault on ^C \[*87* by Anthony Sottile\]
- •
Follow up the libsass upstream: 3.3.0 --- See the release notes of LibSass *3.3.0*. \[*96* by Anthony Sottile\]
### Version 0.8.3
Released on August 2, 2015.
- •
Follow up the libsass upstream: 3.2.5 --- See the release notes of LibSass *3.2.5*. \[*79*, *80* by Anthony Sottile\]
- •
Fixed a bug that **\*.sass** files were ignored. \[*78* by Guilhem MAS-PAITRAULT\]
### Version 0.8.2
Released on May 19, 2015.
- •
Follow up the libsass upstream: 3.2.4 --- See the release notes of LibSass *3.2.3*, and *3.2.4*. \[*69* by Anthony Sottile\]
- •
The default value of *SassMiddleware*'s **error\_status** parameter was changed from **'500 Internal Server Error'** to **'200 OK'** so that Mozilla Firefox can render the error message well. \[*67*, *68*, *70* by zxv\]
### Version 0.8.1
Released on May 14, 2015.
- •
Fixed a bug that there was no **'expanded'** in *sass.OUTPUT\_STYLES* but **'expected'** instead which is a typo. \[*66* by Triangle717\]
- •
Fixed broken FreeBSD build. \[*65* by Toshiharu Moriyama\]
### Version 0.8.0
Released on May 3, 2015.
- •
Follow up the libsass upstream: 3.2.2 --- See the release notes of LibSass *3.2.0*, *3.2.1*, and *3.2.2*. \[*61*, *52*, *56*, *58*, *62*, *64* by Anthony Sottile\]
- •
Compact and expanded output styles \[*37*\]
- •
Strings and interpolation closer to Ruby Sass
- •
The correctness of the generated sourcemap files
- •
Directive buddling
- •
Full support for the **@at-root** directive
- •
Full support for **!global** variable scoping
- •
Now underscored files are ignored when compiling a directory. \[*57* by Anthony Sottile\]
- •
Fixed broken FreeBSD build. \[*34*, *60* by Ilya Baryshev\]
- •
*SassMiddleware* became to log syntax errors if exist during compilation to **sassutils.wsgi.SassMiddleware** logger with level **ERROR**. \[*42*\]
### Version 0.7.0
Released on March 6, 2015.
Anthony Sottile contributed to the most of this release. Huge thanks to him!
- •
Follow up the libsass upstream: 3.1.0 --- See the *release note* of LibSass. \[*38*, *43* by Anthony Sottile\]
- •
Custom functions and imports
- •
Decrementing in **@for** loops
- •
**@debug** and **@error**
- •
**not** operator
- •
**nth()** for maps
- •
**inspect()**
- •
**feature-exists()**
- •
**unique-id()**
- •
**random()**
- •
Added custom functions support. \[*13*, *44* by Anthony Sottile\]
- •
Added *sass.SassFunction* class.
- •
Added **custom\_functions** parameter to *sass.compile()* function.
- •
Added data types for custom functions:
- •
*sass.SassNumber*
- •
*sass.SassColor*
- •
*sass.SassList*
- •
*sass.SassMap*
- •
*sass.SassError*
- •
*sass.SassWarning*
- •
Added **precision** parameter to *sass.compile()* function. \[*39* by Andrea Stagi\]
- •
**sassc** has a new **-p**/**--precision** option. \[*39* by Andrea Stagi\]
### Version 0.6.2
Released on November 25, 2014.
Although 0.6.0--0.6.1 have needed GCC (G++) 4.8+, LLVM Clang 3.3+, now it became back to only need GCC (G++) 4.6+, LLVM Clang 2.9+, or Visual Studio 2013 Update 4+.
- •
Follow up the libsass upstream: 3.0.2 --- See the *release note* of libsass. \[*33* by Rodolphe Pelloux-Prayer\]
- •
Fixed a bug that **sassc --watch** crashed when a file is not compilable on the first try. \[*32* by Alan Justino da Silva\]
- •
Fixed broken build on Windows.
### Version 0.6.1
Released on November 6, 2014.
- •
Follow up the libsass upstream: 3.0.1 --- See the *release note* of LibSass.
- •
Fixed a bug that *SassMiddleware* never closes the socket on some WSGI servers e.g. **eventlet.wsgi**.
### Version 0.6.0
Released on October 27, 2014.
Note that since libsass-python 0.6.0 (and libsass 3.0) it requires C++11 to compile. Although 0.6.2 became back to only need GCC (G++) 4.6+, LLVM Clang 2.9+, from 0.6.0 to 0.6.1 you need GCC (G++) 4.8+, LLVM Clang 3.3+, or Visual Studio 2013 Update 4+.
- •
Follow up the libsass upstream: 3.0 --- See the *release note* of LibSass.
- •
Decent extends support
- •
Basic Sass Maps Support
- •
Better UTF-8 Support
- •
**call()** function
- •
Better Windows Support
- •
Spec Enhancements
- •
Added missing *partial import* support. \[*27* by item4\]
- •
*SOURCE\_COMMENTS* became deprecated.
- •
*sass.compile()*'s parameter **source\_comments** now can take only **bool** instead of **str**. String values like **'none'**, **'line\_numbers'**, and **'map'** become deprecated, and will be obsolete soon.
- •
*build\_directory()* function has a new optional parameter **output\_style**.
- •
**build()** method has a new optional parameter **output\_style**.
- •
Added **--output-style**/**-s** option to *build\_sass* command. \[*25*\]
### Version 0.5.1
Released on September 23, 2014.
- •
Fixed a bug that *SassMiddleware* yielded *str* instead of *bytes* on Python 3.
- •
Fixed several Unicode-related bugs on Windows.
- •
Fixed a bug that *build\_directory()*, *SassMiddleware*, and *build\_sass* don't recursively build subdirectories.
### Version 0.5.0
Released on June 6, 2014.
- •
Follow up the libsass upstream: 2.0 --- See the *release note* of LibSass.
- •
Added indented syntax support (**\*.sass** files).
- •
Added expanded selector support (BEM).
- •
Added string functions.
- •
Fixed UTF-8 support.
- •
Backward incompatibility: broken extends.
### Unstable version 0.4.2.20140529.cd3ee1cbe3
Released on May 29, 2014.
- •
Version scheme changed to use periods (**.**) instead of hyphens (**-**) due to setuptools seems to treat hyphens special.
- •
Fixed malformed packaging that doesn't correctly preserve the package name and version.
### Unstable Version 0.4.2-20140528-cd3ee1cbe3
Released on May 28, 2014.
- •
Follow up the libsass upstream: *cd3ee1cbe34d5316eb762a43127a3de9575454ee*.
### Version 0.4.2
Released on May 22, 2014.
- •
Fixed build failing on Mac OS X 10.8 or earlier. \[*19*\]
- •
Fixed *UnicodeEncodeError* that *Manifest.build\_one()* method rises when the input source contains any non-ASCII Unicode characters.
### Version 0.4.1
Released on May 20, 2014.
- •
Fixed *UnicodeEncodeError* that rise when the input source contains any non-ASCII Unicode characters.
### Version 0.4.0
Released on May 6, 2014.
- •
**sassc** has a new **-w**/**--watch** option.
- •
Expose source maps support:
- •
**sassc** has a new **-m**/**-g**/**--sourcemap** option.
- •
*SassMiddleware* now also creates source map files with filenames followed by **.map** suffix.
- •
*Manifest.build\_one()* method has a new **source\_map** option. This option builds also a source map file with the filename followed by **.map** suffix.
- •
*sass.compile()* has a new optional parameter **source\_comments**. It can be one of *sass.SOURCE\_COMMENTS* keys. It also has a new parameter **source\_map\_filename** which is required only when **source\_comments='map'**.
- •
Fixed Python 3 incompatibility of **sassc** program.
- •
Fixed a bug that multiple **include\_paths** doesn't work on Windows.
### Version 0.3.0
Released on February 21, 2014.
- •
Added support for Python 3.3. \[*7*\]
- •
Dropped support for Python 2.5.
- •
Fixed build failing on Mac OS X. \[*4*, *5*, *6* by Hyungoo Kang\]
- •
Now the builder creates target subdirectories recursively even if they don't exist yet, rather than silently failing. \[*8*, *9* by Philipp Volguine\]
- •
Merged recent changes from libsass 1.0.1: *57a2f62--v1.0.1*.
- •
Supports *variable arguments*.
- •
Supports sourcemaps.
### Version 0.2.4
Released on December 4, 2012.
- •
Added **sassc** CLI executable script.
- •
Added *sass.OUTPUT\_STYLES* constant map.
- •
Merged recent changes from libsass upstream: *e997102--a84b181*.
### Version 0.2.3
Released on October 24, 2012.
- •
*sassutils.distutils*: Prevent double monkey patch of **sdist**.
- •
Merged upstream changes of libsass.
### Version 0.2.2
Released on September 28, 2012.
- •
Fixed a link error on PyPy and Linux.
- •
Fixed build errors on Windows.
### Version 0.2.1
Released on September 12, 2012.
- •
Support Windows.
### Version 0.2.0
Released on August 24, 2012.
- •
Added new *sassutils* package.
- •
Added *sassutils.builder* module to build the whole directory at a time.
- •
Added *sassutils.distutils* module for **distutils** and **setuptools** integration.
- •
Added *sassutils.wsgi* module which provides a development-purpose WSGI middleware.
- •
Added *build\_sass* command for **distutils**/**setuptools**.
### Version 0.1.1
Released on August 18, 2012.
- •
Fixed segmentation fault for reading **filename** which does not exist. Now it raises a proper **exceptions.IOError** exception.
### Version 0.1.0
Released on August 17, 2012. Initial version.
## REFERENCES
### *pysassc* --- SassC compliant command line interface
This provides *SassC* compliant CLI executable named **pysassc**:
```
$ pysassc
Usage: pysassc [options] SCSS_FILE [CSS_FILE]
```
There are options as well:
- **-t \, --style \**
Coding style of the compiled result. The same as *sass.compile()* function's **output\_style** keyword argument. Default is **nested**.
- **-s \, --output-style \**
Alias for -t / --style.
Deprecated since version 0.11.0.
- **-I \, --include-path \**
Optional directory path to find **@import**ed (S)CSS files. Can be multiply used.
- **-m, -g, --sourcemap**
Emit source map. Requires the second argument (output CSS filename). The filename of source map will be the output CSS filename followed by **.map**.
Added in version 0.4.0.
- **-p, --precision**
Set the precision for numbers. Default is 5.
Added in version 0.7.0.
- **--source-comments**
Include debug info in output.
Added in version 0.11.0.
- **--sourcemap-file**
Output file for source map
Added in version 0.17.0.
- **--sourcemap-contents**
Embed sourcesContent in source map.
Added in version 0.17.0.
- **--sourcemap-embed**
Embed sourceMappingUrl as data URI
Added in version 0.17.0.
- **--omit-sourcemap-url**
Omit source map URL comment from output
Added in version 0.17.0.
- **--sourcemap-root**
Base path, will be emitted to sourceRoot in source-map as is
Added in version 0.17.0.
- **-v, --version**
Prints the program version.
- **-h, --help**
Prints the help message.
### *sass* --- Binding of libsass
This simple C extension module provides a very simple binding of **libsass**, which is written in C/C++. It contains only one function and one exception type.
```
>>> import sass
>>> sass.compile(string='a { b { color: blue; } }')
'a b {
color: blue; }
'
```
- **exception sass.CompileError(msg)**
The exception type that is raised by *compile()*. It is a subtype of **exceptions.ValueError**.
- **sass.MODES = frozenset({'dirname', 'filename', 'string'})**
(*frozenset*) The set of keywords *compile()* can take.
- **sass.OUTPUT\_STYLES = {'compact': 2, 'compressed': 3, 'expanded': 1, 'nested': 0}**
(*collections.abc.Mapping*) The dictionary of output styles. Keys are output name strings, and values are flag integers.
- **sass.SOURCE\_COMMENTS = {'default': 1, 'line\_numbers': 1, 'map': 2, 'none': 0}**
(*collections.abc.Mapping*) The dictionary of source comments styles. Keys are mode names, and values are corresponding flag integers.
Added in version 0.4.0.
Deprecated since version 0.6.0.
- **class sass.SassColor(r, g, b, a)**
- **class sass.SassError(msg)**
- **class sass.SassFunction(name, arguments, callable\_)**
Custom function for Sass. It can be instantiated using *from\_lambda()* and *from\_named\_function()* as well.
- **Parameters**
- •
**name** (*str*) -- the function name
- •
**arguments** (*collections.abc.Sequence*) -- the argument names
- •
**callable** (*collections.abc.Callable*) -- the actual function to be called
Added in version 0.7.0.
- **classmethod from\_lambda(name, lambda\_)**
Make a *SassFunction* object from the given **lambda\_** function. Since lambda functions don't have their name, it need its **name** as well. Arguments are automatically inspected.
- **Parameters**
- •
**name** (*str*) -- the function name
- •
**lambda** (**types.LambdaType**) -- the actual lambda function to be called
- **Returns**
a custom function wrapper of the **lambda\_** function
- **Return type**
*SassFunction*
- **classmethod from\_named\_function(function)**
Make a *SassFunction* object from the named **function**. Function name and arguments are automatically inspected.
- **Parameters**
**function** (**types.FunctionType**) -- the named function to be called
- **Returns**
a custom function wrapper of the **function**
- **Return type**
*SassFunction*
- **property signature**
Signature string of the function.
- **class sass.SassList(items, separator, bracketed=False)**
- **class sass.SassMap(\*args, \*\*kwargs)**
Because sass maps can have mapping types as keys, we need an immutable hashable mapping type.
Added in version 0.7.0.
- **class sass.SassNumber(value, unit)**
- **class sass.SassWarning(msg)**
- **sass.and\_join(strings)**
Join the given **strings** by commas with last *' and '* conjunction.
```
>>> and_join(['Korea', 'Japan', 'China', 'Taiwan'])
'Korea, Japan, China, and Taiwan'
```
- **Parameters**
**strings** -- a list of words to join
- **Returns**
a joined string
- **Return type**
*str*, **basestring**
- **sass.compile(\*\*kwargs)**
There are three modes of parameters *compile()* can take: **string**, **filename**, and **dirname**.
The **string** parameter is the most basic way to compile Sass. It simply takes a string of Sass code, and then returns a compiled CSS string.
- **Parameters**
- •
**string** (*str*) -- Sass source code to compile. it's exclusive to **filename** and **dirname** parameters
- •
**output\_style** (*str*) -- an optional coding style of the compiled result. choose one of: **'nested'** (default), **'expanded'**, **'compact'**, **'compressed'**
- •
**source\_comments** (*bool*) -- whether to add comments about source lines. **False** by default
- •
**source\_map\_contents** (*bool*) -- embed include contents in map
- •
**source\_map\_embed** (*bool*) -- embed sourceMappingUrl as data URI
- •
**omit\_source\_map\_url** (*bool*) -- omit source map URL comment from output
- •
**source\_map\_root** (*str*) -- base path, will be emitted in source map as is
- •
**include\_paths** (*collections.abc.Sequence*) -- an optional list of paths to find **@import**ed Sass/CSS source files
- •
**precision** (*int*) -- optional precision for numbers. **5** by default.
- •
**custom\_functions** (*set*, *collections.abc.Sequence*, *collections.abc.Mapping*) -- optional mapping of custom functions. see also below *custom functions* description
- •
**custom\_import\_extensions** -- (ignored, for backward compatibility)
- •
**indented** (*bool*) -- optional declaration that the string is Sass, not SCSS formatted. **False** by default
- •
**importers** (*collections.abc.Callable*) -- optional callback functions. see also below *importer callbacks* description
- **Returns**
the compiled CSS string
- **Return type**
*str*
- **Raises**
*sass.CompileError* -- when it fails for any reason (for example the given Sass has broken syntax)
The **filename** is the most commonly used way. It takes a string of Sass filename, and then returns a compiled CSS string.
- **Parameters**
- •
**filename** (*str*) -- the filename of Sass source code to compile. it's exclusive to **string** and **dirname** parameters
- •
**output\_style** (*str*) -- an optional coding style of the compiled result. choose one of: **'nested'** (default), **'expanded'**, **'compact'**, **'compressed'**
- •
**source\_comments** (*bool*) -- whether to add comments about source lines. **False** by default
- •
**source\_map\_filename** (*str*) -- use source maps and indicate the source map output filename. **None** means not using source maps. **None** by default.
- •
**source\_map\_contents** (*bool*) -- embed include contents in map
- •
**source\_map\_embed** (*bool*) -- embed sourceMappingUrl as data URI
- •
**omit\_source\_map\_url** (*bool*) -- omit source map URL comment from output
- •
**source\_map\_root** (*str*) -- base path, will be emitted in source map as is
- •
**include\_paths** (*collections.abc.Sequence*) -- an optional list of paths to find **@import**ed Sass/CSS source files
- •
**precision** (*int*) -- optional precision for numbers. **5** by default.
- •
**custom\_functions** (*set*, *collections.abc.Sequence*, *collections.abc.Mapping*) -- optional mapping of custom functions. see also below *custom functions* description
- •
**custom\_import\_extensions** -- (ignored, for backward compatibility)
- •
**importers** (*collections.abc.Callable*) -- optional callback functions. see also below *importer callbacks* description
- **Returns**
the compiled CSS string, or a pair of the compiled CSS string and the source map string if **source\_map\_filename** is set
- **Return type**
*str*, *tuple*
- **Raises**
- •
*sass.CompileError* -- when it fails for any reason (for example the given Sass has broken syntax)
- •
**exceptions.IOError** -- when the **filename** doesn't exist or cannot be read
The **dirname** is useful for automation. It takes a pair of paths. The first of the **dirname** pair refers the source directory, contains several Sass source files to compiled. Sass source files can be nested in directories. The second of the pair refers the output directory that compiled CSS files would be saved. Directory tree structure of the source directory will be maintained in the output directory as well. If **dirname** parameter is used the function returns **None**.
- **Parameters**
- •
**dirname** (*tuple*) -- a pair of **(source\_dir, output\_dir)**. it's exclusive to **string** and **filename** parameters
- •
**output\_style** (*str*) -- an optional coding style of the compiled result. choose one of: **'nested'** (default), **'expanded'**, **'compact'**, **'compressed'**
- •
**source\_comments** (*bool*) -- whether to add comments about source lines. **False** by default
- •
**source\_map\_contents** (*bool*) -- embed include contents in map
- •
**source\_map\_embed** (*bool*) -- embed sourceMappingUrl as data URI
- •
**omit\_source\_map\_url** (*bool*) -- omit source map URL comment from output
- •
**source\_map\_root** (*str*) -- base path, will be emitted in source map as is
- •
**include\_paths** (*collections.abc.Sequence*) -- an optional list of paths to find **@import**ed Sass/CSS source files
- •
**precision** (*int*) -- optional precision for numbers. **5** by default.
- •
**custom\_functions** (*set*, *collections.abc.Sequence*, *collections.abc.Mapping*) -- optional mapping of custom functions. see also below *custom functions* description
- •
**custom\_import\_extensions** -- (ignored, for backward compatibility)
- **Raises**
*sass.CompileError* -- when it fails for any reason (for example the given Sass has broken syntax)
The **custom\_functions** parameter can take three types of forms:
*set*/*Sequence* of *SassFunction*s
It is the most general form. Although pretty verbose, it can take any kind of callables like type objects, unnamed functions, and user-defined callables.
```
sass.compile(
...,
custom_functions={
sass.SassFunction('func-name', ('$a', '$b'), some_callable),
...
}
)
```
- ***Mapping* of names to functions**
Less general, but easier-to-use form. Although it's not it can take any kind of callables, it can take any kind of *functions* defined using *def*/*lambda* syntax. It cannot take callables other than them since inspecting arguments is not always available for every kind of callables.
```
sass.compile(
...,
custom_functions={
'func-name': lambda a, b: ...,
...
}
)
```
*set*/*Sequence* of named functions
Not general, but the easiest-to-use form for *named* functions. It can take only named functions, defined using *def*. It cannot take lambdas sinc names are unavailable for them.
```
def func_name(a, b):
return ...
sass.compile(
...,
custom_functions={func_name}
)
```
Newer versions of **libsass** allow developers to define callbacks to be called and given a chance to process **@import** directives. You can define yours by passing in a list of callables via the **importers** parameter. The callables must be passed as 2-tuples in the form:
```
(priority_int, callback_fn)
```
A priority of zero is acceptable; priority determines the order callbacks are attempted.
These callbacks can accept one or two string arguments. The first argument is the path that was passed to the **@import** directive; the second (optional) argument is the previous resolved path, where the **@import** directive was found. The callbacks must either return **None** to indicate the path wasn't handled by that callback (to continue with others or fall back on internal **libsass** filesystem behaviour) or a list of one or more tuples, each in one of three forms:
- •
A 1-tuple representing an alternate path to handle internally; or,
- •
A 2-tuple representing an alternate path and the content that path represents; or,
- •
A 3-tuple representing the same as the 2-tuple with the addition of a "sourcemap".
All tuple return values must be strings. As a not overly realistic example:
```
def my_importer(path, prev):
return [(path, '#' + path + ' { color: red; }')]
sass.compile(
...,
importers=[(0, my_importer)]
)
```
Now, within the style source, attempting to **@import 'button';** will instead attach **color: red** as a property of an element with the imported name.
Added in version 0.4.0: Added **source\_comments** and **source\_map\_filename** parameters.
Changed in version 0.6.0: The **source\_comments** parameter becomes to take only *bool* instead of *str*.
Deprecated since version 0.6.0: Values like **'none'**, **'line\_numbers'**, and **'map'** for the **source\_comments** parameter are deprecated.
Added in version 0.7.0: Added **precision** parameter.
Added in version 0.7.0: Added **custom\_functions** parameter.
Added in version 0.11.0: **source\_map\_filename** no longer implies **source\_comments**.
Added in version 0.17.0: Added **source\_map\_contents**, **source\_map\_embed**, **omit\_source\_map\_url**, and **source\_map\_root** parameters.
Added in version 0.18.0: The importer callbacks can now take a second argument, the previously- resolved path, so that importers can do relative path resolution.
### *sassutils* --- Additional utilities related to Sass
This package provides several additional utilities related to Sass which depends on libsass core (*sass* module).
### *sassutils.builder* --- Build the whole directory
- **class sassutils.builder.Manifest(sass\_path, css\_path=None, wsgi\_path=None, strip\_extension=None)**
Building manifest of Sass/SCSS.
- **Parameters**
- •
**sass\_path** (*str*, **basestring**) -- the path of the directory that contains Sass/SCSS source files
- •
**css\_path** (*str*, **basestring**) -- the path of the directory to store compiled CSS files
- •
**strip\_extension** (*bool*) -- whether to remove the original file extension
- **build(package\_dir, output\_style='nested')**
Builds the Sass/SCSS files in the specified **sass\_path**. It finds **sass\_path** and locates **css\_path** as relative to the given **package\_dir**.
- **Parameters**
- •
**package\_dir** (*str*, **basestring**) -- the path of package directory
- •
**output\_style** (*str*) -- an optional coding style of the compiled result. choose one of: **'nested'** (default), **'expanded'**, **'compact'**, **'compressed'**
- **Returns**
the set of compiled CSS filenames
- **Return type**
*frozenset*
Added in version 0.6.0: The **output\_style** parameter.
- **build\_one(package\_dir, filename, source\_map=False)**
Builds one Sass/SCSS file.
- **Parameters**
- •
**package\_dir** (*str*, **basestring**) -- the path of package directory
- •
**filename** (*str*, **basestring**) -- the filename of Sass/SCSS source to compile
- •
**source\_map** (*bool*) -- whether to use source maps. if **True** it also write a source map to a **filename** followed by **.map** suffix. default is **False**
- **Returns**
the filename of compiled CSS
- **Return type**
*str*, **basestring**
Added in version 0.4.0: Added optional **source\_map** parameter.
- **resolve\_filename(package\_dir, filename)**
Gets a proper full relative path of Sass source and CSS source that will be generated, according to **package\_dir** and **filename**.
- **Parameters**
- •
**package\_dir** (*str*, **basestring**) -- the path of package directory
- •
**filename** (*str*, **basestring**) -- the filename of Sass/SCSS source to compile
- **Returns**
a pair of (sass, css) path
- **Return type**
*tuple*
- **unresolve\_filename(package\_dir, filename)**
Retrieves the probable source path from the output filename. Pass in a .css path to get out a .scss path.
- **Parameters**
- •
**package\_dir** (*str*) -- the path of the package directory
- •
**filename** (*str*) -- the css filename
- **Returns**
the scss filename
- **Return type**
*str*
- **sassutils.builder.SUFFIXES = frozenset({'sass', 'scss'})**
(*frozenset*) The set of supported filename suffixes.
- **sassutils.builder.SUFFIX\_PATTERN = re.compile('\[.\](sass\|scss)$')**
(**re.RegexObject**) The regular expression pattern which matches to filenames of supported *SUFFIXES*.
- **sassutils.builder.build\_directory(sass\_path, css\_path, output\_style='nested', \_root\_sass=None, \_root\_css=None, strip\_extension=False)**
Compiles all Sass/SCSS files in **path** to CSS.
- **Parameters**
- •
**sass\_path** (*str*, **basestring**) -- the path of the directory which contains source files to compile
- •
**css\_path** (*str*, **basestring**) -- the path of the directory compiled CSS files will go
- •
**output\_style** (*str*) -- an optional coding style of the compiled result. choose one of: **'nested'** (default), **'expanded'**, **'compact'**, **'compressed'**
- **Returns**
a dictionary of source filenames to compiled CSS filenames
- **Return type**
*collections.abc.Mapping*
Added in version 0.6.0: The **output\_style** parameter.
### *sassutils.distutils* --- setuptools/distutils integration
This module provides extensions (and some magical monkey-patches, sorry) of the standard **distutils** and **setuptools** (now it's named Distribute) for libsass.
To use this, add **libsass** into **setup\_requires** (not **install\_requires**) option of the **setup.py** script:
```
from setuptools import setup
setup(
# ...,
setup_requires=['libsass >= 0.6.0']
)
```
It will adds *build\_sass* command to the **setup.py** script:
```
$ python setup.py build_sass
```
This commands builds Sass/SCSS files to compiled CSS files of the project and makes the package archive (made by **sdist**, **bdist**, and so on) to include these compiled CSS files.
To set the directory of Sass/SCSS source files and the directory to store compiled CSS files, specify **sass\_manifests** option:
```
from setuptools import find_packages, setup
setup(
name='YourPackage',
packages=find_packages(),
sass_manifests={
'your.webapp': ('static/sass', 'static/css')
},
setup_requires=['libsass >= 0.6.0']
)
```
The option should be a mapping of package names to pairs of paths, e.g.:
```
{
'package': ('static/sass', 'static/css'),
'package.name': ('static/scss', 'static')
}
```
The option can also be a mapping of package names to manifest dictionaries:
```
{
'package': {
'sass_path': 'static/sass',
'css_path': 'static/css',
'strip_extension': True,
},
}
```
Added in version 0.15.0: Added **strip\_extension** so **a.scss** is compiled to **a.css** instead of **a.scss.css**. This option will default to **True** in the future.
Added in version 0.6.0: Added **--output-style**/**-s** option to *build\_sass* command.
- **class sassutils.distutils.build\_sass(dist: Distribution, \*\*kw)**
Builds Sass/SCSS files to CSS files.
- **finalize\_options()**
Set final values for all options/attributes used by the command. Most of the time, each option/attribute/cache should only be set if it does not have any value yet (e.g. **if self.attr is None: self.attr = val**).
- **get\_package\_dir(package)**
Returns the directory, relative to the top of the source distribution, where package **package** should be found (at least according to the **package\_dir** option, if any).
Copied from **distutils.command.build\_py.get\_package\_dir()** method.
- **initialize\_options()**
Set or (reset) all options/attributes/caches used by the command to their default values. Note that these values may be overwritten during the build.
- **run()**
Execute the actions intended by the command. (Side effects **SHOULD** only take place when *run()* is executed, for example, creating new files or writing to the terminal output).
- **sassutils.distutils.validate\_manifests(dist, attr, value)**
Verifies that **value** is an expected mapping of package to *sassutils.builder.Manifest*.
### *sassutils.wsgi* --- WSGI middleware for development purpose
- **class sassutils.wsgi.SassMiddleware(app, manifests, package\_dir={}, error\_status='200 OK')**
WSGI middleware for development purpose. Every time a CSS file has requested it finds a matched Sass/SCSS source file and then compiled it into CSS.
It shows syntax errors in three ways:
- **Heading comment**
The result CSS includes detailed error message in the heading CSS comment e.g.:
```
/*
Error: invalid property name
*/
```
- **Red text in body:before**
The result CSS draws detailed error message in **:before** pseudo-class of **body** element e.g.:
```
body:before {
content: 'Error: invalid property name';
color: maroon;
background-color: white;
}
```
In most cases you could be aware of syntax error by refreshing your working document because it will removes all other styles and leaves only a red text.
- ***logging***
It logs syntax errors if exist during compilation to **sassutils.wsgi.SassMiddleware** logger with level **ERROR**.
To enable this:
```
from logging import Formatter, StreamHandler, getLogger
logger = getLogger('sassutils.wsgi.SassMiddleware')
handler = StreamHandler(level=logging.ERROR)
formatter = Formatter(fmt='*' * 80 + '\n%(message)s\n' + '*' * 80)
handler.setFormatter(formatter)
logger.addHandler(handler)
```
Or simply:
```
import logging
logging.basicConfig()
```
- **Parameters**
- •
**app** (*collections.abc.Callable*) -- the WSGI application to wrap
- •
**manifests** (*collections.abc.Mapping*) -- build settings. the same format to **setup.py** script's **sass\_manifests** option
- •
**package\_dir** (*collections.abc.Mapping*) -- optional mapping of package names to directories. the same format to **setup.py** script's **package\_dir** option
Changed in version 0.4.0: It creates also source map files with filenames followed by **.map** suffix.
Added in version 0.8.0: It logs syntax errors if exist during compilation to **sassutils.wsgi.SassMiddleware** logger with level **ERROR**.
- **static quote\_css\_string(s)**
Quotes a string as CSS string literal.
## CREDIT
Hong Minhee wrote this Python binding of *LibSass*.
Hampton Catlin and Aaron Leung wrote *LibSass*, which is portable C/C++ implementation of *Sass*.
Hampton Catlin originally designed *Sass* language and wrote the first reference implementation of it in Ruby.
The above three are all distributed under *MIT license*.
## OPEN SOURCE
- **GitHub (Git repository + issues)**
*https://github.com/sass/libsass-python*
GitHub Actions (linux + macos + windows)
*Build Status*.UNINDENT
- **PyPI**
*https://pypi.org/pypi/libsass/* *PyPI*.TP **Changelog** *Changelog*
## INDICES AND TABLES
- •
*Index*
- •
*Module Index*
- •
*Search Page*
## AUTHOR
Hong Minhee
## COPYRIGHT
2024, Hong Minhee