node-sass
Supported Node.js versions vary by release, please consult the releases page
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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: https://www.npmjs.com/package/node-sass
Follow @nodesass on twitter for release updates: https://twitter.com/nodesass
Install
npm install node-sass
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.**
SyntaxError: Use of const in strict mode.
Having installation troubles? Check out our Troubleshooting guide.
Install from mirror in China
npm install -g mirror-config-china --registry=http://registry.npm.taobao.org
npm install node-sass
Usage
var sass = require('node-sass');
sass.render({
file: scss_filename,
[, options..]
}, function(err, result) { });
var result = sass.renderSync({
data: scss_content
[, options..]
});
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 encounteredprev (String)
- the previously resolved pathdone (Function)
- a callback function to invoke on async completion, takes an object literal containing
file (String)
- an alternate path for LibSass to use ORcontents (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:
done(new Error('doesn\'t exist!'));
return new Error('nothing to do here');
-
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 numbergetUnit()
/ 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:
var Color = require('node-sass').types.Color,
c1 = new Color(255, 0, 0),
c2 = new Color(0xff0088cc);
types.Boolean(value)
getValue()
: gets the enclosed booleantypes.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 separatorgetLength()
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
sass.renderSync({
data: '#{headings(2,5)} { color: #08c; }',
functions: {
'headings($from: 0, $to: 6)': function(from, to) {
var i, f = from.getValue(), t = to.getValue(),
list = new sass.types.List(t - f + 1);
for (i = f; i <= t; i++) {
list.setValue(i - f, new sass.types.String('h' + i));
}
return list;
}
}
});
includePaths
- Type:
Array<String>
- 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)
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
sass.render({
...
outFile: yourPathTotheFile,
}, function(error, result) {
if(!error){
fs.writeFile(yourPathTotheFile, result.css, function(err){
if(!err){
}
});
}
});
});
outputStyle
- Type:
String
- Default:
nested
- Values:
nested
, expanded
, compact
, compressed
Determines the output format of the final CSS style.
precision
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.
- 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
Special: Setting the sourceMap
option requires also setting the outFile
option
Enables the outputting of a source map during render
and renderSync
. When sourceMap === true
, the value of outFile
is used as the target output location for the source map. 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 mapstats
(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 filestart
(Number) - Date.now() before the compilationend
(Number) - Date.now() after the compilationduration
(Number) - end - startincludedFiles
(Array) - Absolute paths to all related scss files in no particular order.
Examples
var sass = require('node-sass');
sass.render({
file: '/path/to/myFile.scss',
data: 'body{background:blue; a{color:black;}}',
importer: function(url, prev, done) {
someAsyncFunction(url, prev, function(result){
done({
file: result.path,
contents: result.data
});
});
var result = someSyncFunction(url, prev);
return {file: result.path, contents: result.data};
},
includePaths: [ 'lib/', 'mod/' ],
outputStyle: 'compressed'
}, function(error, result) {
if (error) {
console.log(error.status);
console.log(error.column);
console.log(error.message);
console.log(error.line);
}
else {
console.log(result.css.toString());
console.log(result.stats);
console.log(result.map.toString());
console.log(JSON.stringify(result.map));
}
});
var result = sass.renderSync({
file: '/path/to/file.scss',
data: 'body{background:blue; a{color:black;}}',
outputStyle: 'compressed',
outFile: '/to/my/output.css',
sourceMap: true,
importer: function(url, prev, done) {
someAsyncFunction(url, prev, function(result){
done({
file: result.path,
contents: result.data
});
});
var result = someSyncFunction(url, prev);
return {file: result.path, contents: result.data};
}
}));
console.log(result.css);
console.log(result.map);
console.log(result.stats);
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:
var sass = require('node-sass');
console.log(sass.info);
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 has created a Brackets extension based on node-sass: https://github.com/jasonsanjose/brackets-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's official sass plugin uses node-sass by default, and automatically falls back to ruby if use of Compass is detected: https://github.com/brunch/sass-brunch
Connect/Express middleware
Recompile .scss
files automatically for connect and express based http servers.
This functionality has been moved to node-sass-middleware
in node-sass v1.0.0
DocPad Plugin
@10xLaCroixDrinker wrote a DocPad plugin that compiles .scss
files using node-sass: https://github.com/10xLaCroixDrinker/docpad-plugin-nodesass
Duo.js extension
@stephenway has created an extension that transpiles Sass to CSS using node-sass with duo.js
https://github.com/duojs/sass
Grunt extension
@sindresorhus has created a set of grunt tasks based on node-sass: https://github.com/sindresorhus/grunt-sass
Gulp extension
@dlmanning has created a gulp sass plugin based on node-sass: https://github.com/dlmanning/gulp-sass
Harp
@sintaxi’s Harp web server implicitly compiles .scss
files using node-sass: https://github.com/sintaxi/harp
Metalsmith plugin
@stevenschobert has created a metalsmith plugin based on node-sass: https://github.com/stevenschobert/metalsmith-sass
Meteor plugin
@fourseven has created a meteor plugin based on node-sass: https://github.com/fourseven/meteor-scss
Mimosa module
@dbashford has created a Mimosa module for sass which includes node-sass: https://github.com/dbashford/mimosa-sass
Example App
There is also an example connect app here: https://github.com/andrew/node-sass-example
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:
git clone --recursive https://github.com/sass/node-sass.git
cd node-sass
npm install
node scripts/build -f
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] <input> [output]
Or:
cat <input> | node-sass > output
Example:
node-sass src/style.scss dest/style.css
Options:
-w, --watch Watch a directory or file
-r, --recursive Recursively watch directories or files
-o, --output Output directory
-x, --omit-source-map-url Omit source map URL comment from output
-i, --indented-syntax Treat data from stdin as sass code (versus scss)
-q, --quiet Suppress log output except on error
-v, --version Prints version info
--output-style CSS output style (nested | expanded | compact | compressed)
--indent-type Indent type for output CSS (space | tab)
--indent-width Indent width; number of spaces or tabs (maximum value: 10)
--linefeed Linefeed style (cr | crlf | lf | lfcr)
--source-comments Include debug info in output
--source-map Emit source map
--source-map-contents Embed include contents in map
--source-map-embed Embed sourceMappingUrl as data URI
--source-map-root Base path, will be emitted in source-map as is
--include-path Path to look for imported files
--follow Follow symlinked directories
--precision The amount of precision allowed in decimal numbers
--error-bell Output a bell character on errors
--importer Path to .js file containing custom importer
--functions Path to .js file containing custom functions
--help Print usage info
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 |
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/
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:
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.