Sass

Node.js bindings to libsass

CSS Processor
sass/node-sassnode-sass

README

node-sass


Warning: LibSass and Node Sass are deprecated.
While they will continue to receive maintenance releases indefinitely, there are no
plans to add additional features or compatibility with any new CSS or Sass features.
Projects that still use it should move onto
Dart Sass.

Node version support policy


1. Supported Node.js versions vary by release, please consult the releases page.
1. Node versions that hit end of life , will be dropped from support at each node-sass release (major, minor).
1. We will stop building binaries for unsupported releases, testing for breakages in dependency compatibility, but we will not block installations for those that want to support themselves.
1. New node release require minor internal changes along with support from CI providers (AppVeyor, GitHub Actions). We will open a single issue for interested parties to subscribe to, and close additional issues.

Below is a quick guide for minimum and maximum supported versions of node-sass:

NodeJS  | Supported node-sass version | Node Module
Node 19 | 8.0+                        | 111
Node 18 | 8.0+                        | 108
Node 17 | 7.0+, <8.0                  | 102
Node 16 | 6.0+                        | 93
Node 15 | 5.0+, <7.0                  | 88
Node 14 | 4.14+                       | 83
Node 13 | 4.13+, <5.0                 | 79
Node 12 | 4.12+, <8.0                 | 72
Node 11 | 4.10+, <5.0                 | 67
Node 10 | 4.9+, <6.0                  | 64
Node 8  | 4.5.3+, <5.0                | 57
Node <8 | <5.0                        | <57

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Node-sass is a library that provides binding for Node.js to [LibSass], the C version of the popular stylesheet preprocessor, Sass.

It allows you to natively compile .scss files to css at incredible speed and automatically via a connect middleware.

Find it on npm:

Follow @nodesass on twitter for release updates:

Install


  1. ``` sh
  2. npm install node-sass
  3. ```

Some users have reported issues installing on Ubuntu due to node being registered to another package. Follow the official NodeJS docs to install NodeJS so that#!/usr/bin/env node correctly resolves.

Compiling on Windows machines requires the node-gyp prerequisites.

Are you seeing the following error? Check out our Troubleshooting guide.

  1. ```
  2. SyntaxError: Use of const in strict mode.
  3. ```

Having installation troubles? Check out our Troubleshooting guide.

Install from mirror in China


  1. ``` sh
  2. npm install -g mirror-config-china --registry=https://registry.npmmirror.com
  3. npm install node-sass
  4. ```

Usage


  1. ``` js
  2. var sass = require('node-sass');
  3. sass.render({
  4.   file: scss_filename,
  5.   [, options..]
  6. }, function(err, result) { /*...*/ });
  7. // OR
  8. var result = sass.renderSync({
  9.   data: scss_content
  10.   [, options..]
  11. });
  12. ```

Options


file


Type: String
Default: null

Special: file or data must be specified

Path to a file for [LibSass] to compile.

data


Type: String
Default: null

Special: file or data must be specified

A string to pass to [LibSass] to compile. It is recommended that you use includePaths in conjunction with this so that [LibSass] can find files when using the @import directive.

importer (>= v2.0.0) - _experimental_


This is an experimental LibSass feature. Use with caution.

Type: Function | Function[] signature function(url, prev, done)
Default: undefined

Function Parameters and Information:

url (String) - the path in import as-is, which [LibSass] encountered
prev (String) - the previously resolved path
done (Function) - a callback function to invoke on async completion, takes an object literal containing
  file (String) - an alternate path for [LibSass] to use OR
  contents (String) - the imported contents (for example, read from memory or the file system)

Handles when [LibSass] encounters the @import directive. A custom importer allows extension of the [LibSass] engine in both a synchronous and asynchronous manner. In both cases, the goal is to either return or call done() with an object literal. Depending on the value of the object literal, one of two things will happen.

When returning or calling done() with { file: "String" }, the new file path will be assumed for the @import. It's recommended to be mindful of the value of prev in instances where relative path resolution may be required.

When returning or calling done() with { contents: "String" }, the string value will be used as if the file was read in through an external source.

Starting from v3.0.0:

this refers to a contextual scope for the immediate run of sass.render or sass.renderSync

importers can return error and LibSass will emit that error in response. For instance:

  1. ``` js
  2.   done(new Error('doesn\'t exist!'));
  3.   // or return synchronously
  4.   return new Error('nothing to do here');
  5. ```

importer can be an array of functions, which will be called by LibSass in the order of their occurrence in array. This helps user specify special importer for particular kind of path (filesystem, http). If an importer does not want to handle a particular path, it should return null. See functions section for more details on Sass types.

functions (>= v3.0.0) - _experimental_


This is an experimental LibSass feature. Use with caution.

functions is an Object that holds a collection of custom functions that may be invoked by the sass files being compiled. They may take zero or more input parameters and must return a value either synchronously (return ...;) or asynchronously (done();). Those parameters will be instances of one of the constructors contained in the require('node-sass').types hash. The return value must be of one of these types as well. See the list of available types below:

types.Number(value [, unit = ""])


getValue()/ setValue(value) : gets / sets the numerical portion of the number
getUnit() / setUnit(unit) : gets / sets the unit portion of the number

types.String(value)


getValue() / setValue(value) : gets / sets the enclosed string

types.Color(r, g, b [, a = 1.0]) or types.Color(argb)


getR() / setR(value) : red component (integer from 0 to 255)
getG() / setG(value) : green component (integer from 0 to 255)
getB() / setB(value) : blue component (integer from 0 to 255)
getA() / setA(value) : alpha component (number from 0 to 1.0)

Example:

  1. ``` js
  2. var Color = require('node-sass').types.Color,
  3.   c1 = new Color(255, 0, 0),
  4.   c2 = new Color(0xff0088cc);
  5. ```

types.Boolean(value)


getValue() : gets the enclosed boolean
types.Boolean.TRUE : Singleton instance of types.Boolean that holds "true"
types.Boolean.FALSE : Singleton instance of types.Boolean that holds "false"

types.List(length [, commaSeparator = true])


getValue(index) / setValue(index, value) : value must itself be an instance of one of the constructors in sass.types.
getSeparator() / setSeparator(isComma) : whether to use commas as a separator
getLength()

types.Map(length)


getKey(index) / setKey(index, value)
getValue(index) / setValue(index, value)
getLength()

types.Null()


types.Null.NULL : Singleton instance of types.Null.

Example


  1. ``` js
  2. sass.renderSync({
  3.   data: '#{headings(2,5)} { color: #08c; }',
  4.   functions: {
  5.     'headings($from: 0, $to: 6)': function(from, to) {
  6.       var i, f = from.getValue(), t = to.getValue(),
  7.           list = new sass.types.List(t - f + 1);

  9.       for (i = f; i <= t; i++) {
  10.         list.setValue(i - f, new sass.types.String('h' + i));
  11.       }

  13.       return list;
  14.     }
  15.   }
  16. });
  17. ```

includePaths


* Type: `Array`
Default: []

An array of paths that [LibSass] can look in to attempt to resolve your @import declarations. When using data, it is recommended that you use this.

indentedSyntax


Type: Boolean
Default: false

true values enable Sass Indented Syntax for parsing the data string or file.

__Note:__ node-sass/libsass will compile a mixed library of scss and indented syntax (.sass) files with the Default setting (false) as long as .sass and .scss extensions are used in filenames.

indentType (>= v3.0.0)


Type: String
Default: space

Used to determine whether to use space or tab character for indentation.

indentWidth (>= v3.0.0)


Type: Number
Default: 2
Maximum: 10

Used to determine the number of spaces or tabs to be used for indentation.

linefeed (>= v3.0.0)


Type: String
Default: lf

Used to determine whether to use cr, crlf, lf or lfcr sequence for line break.

omitSourceMapUrl


Type: Boolean
Default: false

Special: When using this, you should also specify outFile to avoid unexpected behavior.

true values disable the inclusion of source map information in the output file.

outFile


Type: String | null
Default: null

Special: Required when sourceMap is a truthy value

Specify the intended location of the output file. Strongly recommended when outputting source maps so that they can properly refer back to their intended files.

Attention enabling this option will not write the file on disk for you, it's for internal reference purpose only (to generate the map for example).

Example on how to write it on the disk

  1. ``` js
  2. sass.render({
  3.     ...
  4.     outFile: yourPathTotheFile,
  5.   }, function(error, result) { // node-style callback from v3.0.0 onwards
  6.     if(!error){
  7.       // No errors during the compilation, write this result on the disk
  8.       fs.writeFile(yourPathTotheFile, result.css, function(err){
  9.         if(!err){
  10.           //file written on disk
  11.         }
  12.       });
  13.     }
  14.   });
  15. });
  16. ```

outputStyle


Type: String
Default: nested
Values: nested, expanded, compact, compressed

Determines the output format of the final CSS style.

precision


Type: Integer
Default: 5

Used to determine how many digits after the decimal will be allowed. For instance, if you had a decimal number of 1.23456789 and a precision of 5, the result will be 1.23457 in the final CSS.

sourceComments


Type: Boolean
Default: false

true Enables the line number and file where a selector is defined to be emitted into the compiled CSS as a comment. Useful for debugging, especially when using imports and mixins.

sourceMap


Type: Boolean | String | undefined
Default: undefined

Enables source map generation during render and renderSync.

When sourceMap === true, the value of outFile is used as the target output location for the source map with the suffix .map appended. If no outFile is set, sourceMap parameter is ignored.

When typeof sourceMap === "string", the value of sourceMap will be used as the writing location for the file.

sourceMapContents


Type: Boolean
Default: false

true includes the contents in the source map information

sourceMapEmbed


Type: Boolean
Default: false

true embeds the source map as a data URI

sourceMapRoot


Type: String
Default: undefined

the value will be emitted as sourceRoot in the source map information

render Callback (>= v3.0.0)


node-sass supports standard node style asynchronous callbacks with the signature of function(err, result). In error conditions, the error argument is populated with the error object. In success conditions, the result object is populated with an object describing the result of the render call.

Error Object


message (String) - The error message.
line (Number) - The line number of error.
column (Number) - The column number of error.
status (Number) - The status code.
file (String) - The filename of error. In case file option was not set (in favour of data), this will reflect the value stdin.

Result Object


css (Buffer) - The compiled CSS. Write this to a file, or serve it out as needed.
map (Buffer) - The source map
stats (Object) - An object containing information about the compile. It contains the following keys:
  entry (String) - The path to the scss file, or data if the source was not a file
  start (Number) - Date.now() before the compilation
  end (Number) - Date.now() after the compilation
  duration (Number) - end - start
  includedFiles (Array) - Absolute paths to all related scss files in no particular order.

Examples


  1. ``` js
  2. var sass = require('node-sass');
  3. sass.render({
  4.   file: '/path/to/myFile.scss',
  5.   data: 'body{background:blue; a{color:black;}}',
  6.   importer: function(url, prev, done) {
  7.     // url is the path in import as is, which LibSass encountered.
  8.     // prev is the previously resolved path.
  9.     // done is an optional callback, either consume it or return value synchronously.
  10.     // this.options contains this options hash, this.callback contains the node-style callback
  11.     someAsyncFunction(url, prev, function(result){
  12.       done({
  13.         file: result.path, // only one of them is required, see section Special Behaviours.
  14.         contents: result.data
  15.       });
  16.     });
  17.     // OR
  18.     var result = someSyncFunction(url, prev);
  19.     return {file: result.path, contents: result.data};
  20.   },
  21.   includePaths: [ 'lib/', 'mod/' ],
  22.   outputStyle: 'compressed'
  23. }, function(error, result) { // node-style callback from v3.0.0 onwards
  24.   if (error) {
  25.     console.log(error.status); // used to be "code" in v2x and below
  26.     console.log(error.column);
  27.     console.log(error.message);
  28.     console.log(error.line);
  29.   }
  30.   else {
  31.     console.log(result.css.toString());

  33.     console.log(result.stats);

  35.     console.log(result.map.toString());
  36.     // or better
  37.     console.log(JSON.stringify(result.map)); // note, JSON.stringify accepts Buffer too
  38.   }
  39. });
  40. // OR
  41. var result = sass.renderSync({
  42.   file: '/path/to/file.scss',
  43.   data: 'body{background:blue; a{color:black;}}',
  44.   outputStyle: 'compressed',
  45.   outFile: '/to/my/output.css',
  46.   sourceMap: true, // or an absolute or relative (to outFile) path
  47.   importer: function(url, prev, done) {
  48.     // url is the path in import as is, which LibSass encountered.
  49.     // prev is the previously resolved path.
  50.     // done is an optional callback, either consume it or return value synchronously.
  51.     // this.options contains this options hash
  52.     someAsyncFunction(url, prev, function(result){
  53.       done({
  54.         file: result.path, // only one of them is required, see section Special Behaviours.
  55.         contents: result.data
  56.       });
  57.     });
  58.     // OR
  59.     var result = someSyncFunction(url, prev);
  60.     return {file: result.path, contents: result.data};
  61.   }
  62. });

  64. console.log(result.css);
  65. console.log(result.map);
  66. console.log(result.stats);
  67. ```

Special behaviours


In the case that both file and data options are set, node-sass will give precedence to data and use file to calculate paths in sourcemaps.

Version information (>= v2.0.0)


Both node-sass and libsass version info is now exposed via the info method:

  1. ``` js
  2. var sass = require('node-sass');

  4. console.log(sass.info);

  6. /*
  7.   it will output something like:

  9.   node-sass       2.0.1   (Wrapper)       [JavaScript]
  10.   libsass         3.1.0   (Sass Compiler) [C/C++]
  11. */
  12. ```

Since node-sass >=v3.0.0 LibSass version is determined at run time.

Integrations


Listing of community uses of node-sass in build tools and frameworks.

Brackets extension


[@jasonsanjose](https://github.com/jasonsanjose) has created a [Brackets](http://brackets.io) extension based on node-sass: . When editing Sass files, the extension compiles changes on save. The extension also integrates with Live Preview to show Sass changes in the browser without saving or compiling.

Brunch plugin


[Brunch](http://brunch.io)'s official sass plugin uses node-sass by default, and automatically falls back to ruby if use of Compass is detected:

Connect/Express middleware


Recompile .scss files automatically for connect and express based http servers.

This functionality has been moved to [node-sass-middleware](https://github.com/sass/node-sass-middleware) in node-sass v1.0.0

DocPad Plugin


[@10xLaCroixDrinker](https://github.com/10xLaCroixDrinker) wrote a [DocPad](http://docpad.org/) plugin that compiles `.scss` files using node-sass:

Duo.js extension


@stephenway has created an extension that transpiles Sass to CSS using node-sass with duo.js

Grunt extension


[@sindresorhus](https://github.com/sindresorhus/) has created a set of grunt tasks based on node-sass:

Gulp extension


[@dlmanning](https://github.com/dlmanning/) has created a gulp sass plugin based on node-sass:

Harp


[@sintaxi](https://github.com/sintaxi)’s Harp web server implicitly compiles `.scss` files using node-sass:

Metalsmith plugin


[@stevenschobert](https://github.com/stevenschobert/) has created a metalsmith plugin based on node-sass:

Meteor plugin


[@fourseven](https://github.com/fourseven) has created a meteor plugin based on node-sass:

Mimosa module


[@dbashford](https://github.com/dbashford) has created a Mimosa module for sass which includes node-sass:

Example App


There is also an example connect app here:

Rebuilding binaries


Node-sass includes pre-compiled binaries for popular platforms, to add a binary for your platform follow these steps:

Check out the project:

  1. ``` sh
  2. git clone --recursive https://github.com/sass/node-sass.git
  3. cd node-sass
  4. npm install
  5. node scripts/build -f  # use -d switch for debug release
  6. # if succeeded, it will generate and move
  7. # the binary in vendor directory.
  8. ```

Command Line Interface


The interface for command-line usage is fairly simplistic at this stage, as seen in the following usage section.

Output will be sent to stdout if the --output flag is omitted.

Usage


`node-sass [options] [output]`
Or:
`cat | node-sass > output`

Example:

node-sass src/style.scss dest/style.css

Options:

  1. ``` sh
  2.     -w, --watch                Watch a directory or file
  3.     -r, --recursive            Recursively watch directories or files
  4.     -o, --output               Output directory
  5.     -x, --omit-source-map-url  Omit source map URL comment from output
  6.     -i, --indented-syntax      Treat data from stdin as sass code (versus scss)
  7.     -q, --quiet                Suppress log output except on error
  8.     -v, --version              Prints version info
  9.     --output-style             CSS output style (nested | expanded | compact | compressed)
  10.     --indent-type              Indent type for output CSS (space | tab)
  11.     --indent-width             Indent width; number of spaces or tabs (maximum value: 10)
  12.     --linefeed                 Linefeed style (cr | crlf | lf | lfcr)
  13.     --source-comments          Include debug info in output
  14.     --source-map               Emit source map
  15.     --source-map-contents      Embed include contents in map
  16.     --source-map-embed         Embed sourceMappingUrl as data URI
  17.     --source-map-root          Base path, will be emitted in source-map as is
  18.     --include-path             Path to look for imported files
  19.     --follow                   Follow symlinked directories
  20.     --precision                The amount of precision allowed in decimal numbers
  21.     --error-bell               Output a bell character on errors
  22.     --importer                 Path to .js file containing custom importer
  23.     --functions                Path to .js file containing custom functions
  24.     --help                     Print usage info
  25. ```

The input can be either a single .scss or .sass, or a directory. If the input is a directory the --output flag must also be supplied.

Also, note --importer takes the (absolute or relative to pwd) path to a js file, which needs to have a default module.exports set to the importer function. See our test fixtures for example.

The --source-map option accepts a boolean value, in which case it replaces destination extension with .css.map. It also accepts path to .map file and even path to the desired directory.
When compiling a directory --source-map can either be a boolean value or a directory.

Binary configuration parameters


node-sass supports different configuration parameters to change settings related to the sass binary such as binary name, binary path or alternative download path. Following parameters are supported by node-sass:

Variable name            | .npmrc parameter         | Process argument           | Value
SASS_BINARY_NAME         | sass_binary_name         | --sass-binary-name         | path
SASS_BINARY_SITE         | sass_binary_site         | --sass-binary-site         | URL
SASS_BINARY_PATH         | sass_binary_path         | --sass-binary-path         | path
SASS_BINARY_DIR          | sass_binary_dir          | --sass-binary-dir          | path
SASS_REJECT_UNAUTHORIZED | sass_reject_unauthorized | --sass-reject-unauthorized | value

These parameters can be used as environment variable:

E.g. export SASS_BINARY_SITE=http://example.com/

As local or global .npmrc configuration file:

E.g. sass_binary_site=http://example.com/

As a process argument:

E.g. npm install node-sass --sass-binary-site=http://example.com/

If you are using self-signed certificates for your binary then SASS_REJECT_UNAUTHORIZED will override (rejectUnauthorized)[https://nodejs.org/docs/latest/api/tls.html#tls_tls_createserver_options_secureconnectionlistener].

Post-install Build


Install runs only two Mocha tests to see if your machine can use the pre-built [LibSass] which will save some time during install. If any tests fail it will build from source.

Maintainers


This module is brought to you and maintained by the following people:

Michael Mifsud - Project Lead (Github / Twitter)
Andrew Nesbitt (Github / Twitter)
Dean Mao (Github / Twitter)
Brett Wilkins (Github / Twitter)
Keith Cirkel (Github / Twitter)
Laurent Goderre (Github / Twitter)
Nick Schonning (Github / Twitter)
Adeel Mujahid (Github / Twitter)

Contributors


We <3 our contributors! A special thanks to all those who have clocked in some dev time on this project, we really appreciate your hard work. You can find a full list of those people here.

Note on Patches/Pull Requests


Check out our Contributing guide

Copyright


Copyright (c) 2015 Andrew Nesbitt. See LICENSE for details.

[LibSass]: https://github.com/sass/libsass