#sass-inline-svg-utf8

Inline SVGs in your CSS as html-encoded UTF-8 with node-sass.

Inlining is good because fewer requests, html-encoded is good for SVG because it is smaller than base64 (by about 30% on average).

String replacement is good because you can use 'variables' in your SVG source files and replace them on a per-inlined-instance basis. Use case? You need a white, a black, and a blue arrow icon, and can create them on the fly when inling from a single source file. Good because if the arrow needs to be changed, you only have to change on file, not three.

Install

npm install --save-dev sass-inline-svg-utf8

Usage

var sass = require('node-sass');
var sassInlineSVG = require('sass-inline-svg-utf8');
var pathToSvgDir = path.resolve(__dirname,'./my-path-to-direcory-with-swg') 

sass.render({
  functions: sassInlineSVG(pathToSvgDir), //pathToSvgDir - optional.
  file: file,
  outfile: outfile
}, function(error, result) {
    /* Your code here */
});

In your Sass:

.myClass {
  //path can be relative to the directory, where you execute your build script
  background-image: inline-svg('./images/logo.svg');
}
.myClass {
  //you can provide path to the directory with svg files as a parameter to function and use reletive pathes
  background-image: inline-svg('logo.svg');
}
.myClass {
  //path can be relative to the current .sass file. 
  background-image: inline-svg('../images/logo.svg');
}

For optimal results and minimal filesize, run your SVGs through SVGO first (Actually, I'm on the fence whether to include SVGO optimization by default when inlining, but I’m not sure because of various settings/complexity). If you have a strong opinion on that, let’s dicuss here.

Advanced Usage w/ String replacement

In your SVG source, you can use variable strings to replace when inlining:

<path fill="fillcolor" […] />

In your Sass, you can pass a map of variables to replace as a second parameter:

.myClass {
  background-image: inline-svg('./images/arrow.svg', { fillcolor: '#000000'});
}

This will replace all occurences of fillcolor in the SVG file with #000000 in the inlined SVG.

If you want to use $-prepended variable names to match your Sass variables, quote them in the Sass map like { '$fillcolor': '#000000' }.

This will result in (not html encoded here for readability):

<path fill="#000000" […] />

So to create three instances of the same SVG source with different fill colors in your CSS:

.red-arrow {
  background-image: inline-svg( './images/arrow.svg', ( fillcolor: 'red'));
}

.blue-arrow {
  background-image: inline-svg( './images/arrow.svg', ( fillcolor: 'blue'));
}

.black-arrow {
  background-image: inline-svg( './images/arrow.svg', ( fillcolor: 'black'));
}

Using colors

To use non-named colors like hex, rgba etc., these need to be passed as a quoted string (this is down to the current behavior of node-sass/libsass):

.white-arrow {
  background-image: inline-svg( './images/arrow.svg', ( fillcolor: '#fff'));
}

Whn using variables that may contain colors, these need to be evaluated to be on the safe side:

.custom-arrow {
  background-image: inline-svg( './images/arrow.svg', ( fillcolor: #{$custom-color}));
}

I have opened this issue with node-sass to make the quoting/evaluating unnecessary (fingers crossed…)