Babel Preset SVGR
SVGR is the most popular library for
importing SVG images into React applications (~5.8M weekly downloads).
It provides SVG Webpack loader, Node API, and CLI tool, but there was no
way to use it with Babel (see https://github.com/smooth-code/svgr/issues/306,
https://github.com/smooth-code/svgr/issues/252).
This preset allows to transform SVG files into React components with
SVGR and Babel. It works with any Babel setup (Babel CLI, @babel/node
,
@babel/register
, Webpack babel-loader
). If you use Hot Module Reloading
in React, SVGs handled by this preset are correctly reloaded when changed.
Content
Setup
-
Install the preset
npm install --save-dev @dr.pogodin/babel-preset-svgr
Depending on your setup, you may need to use --save
flag to save it as
a regular dependency, rather than the development one.
-
Add the preset to your Babel config, e.g.
{
"presets": [
"@babel/env",
"@babel/react",
"@dr.pogodin/babel-preset-svgr"
]
}
-
Instruct Babel to transform SVG files.
-
If you use Webpack and babel-loader
, add SVG rule inside Webpack config
as:
module.exports = {
module: {
rules: [{
test: /\.(jsx?|svg)$/
exclude: [/node_modules/],
loader: 'babel-loader',
options: {
}
}]
}
}
With such setup you don't need to use @svgr/webpack
loader for SVG files,
Babel will take care about everything.
-
If you use @babel/node
, or @babel/register
you need to add .svg
into
their extensions
option. For @babel/node
use the flag
--extensions '.js','.jsx','.svg'
, for @babel/register
use
extensions: ['.js', '.jsx', '.svg']
array inside the options object.
-
If you use Babel CLI and specify individual file(s) to compile, it will
work out of the box for SVGs. If you use it to compile entire directories
you'll need a dedicated compilation pass for SVG files with the flags
--extensions '.svg' --keep-file-extension
. In this dedicated pass
Babel will only compile SVG assets, and it will keep their extensions.
In a separate pass you'll compile JS(X) files as usual. The dedicated
pass is necessary, as Babel currently either replaces all output file
extensions to .js
, or keeps all original ones. In our case we need
to keep .svg
extensions only
(corresponding feature request in the Babel repo).
Under the Hood
This preset wraps the standard Babel parser into a simple logic which checks
for .svg
extensions of input, and if met, it runs the input code through SVGR
before passing it to the Babel parser. For other file types it passes
the code directly into Babel parser.
If your project already depends on a customized Babel parser, you can provide
its path via the parser
option of this preset. It will require()
and use
your parser then.
You also can pass in custom SVGR options via svgr
field.
BEWARE: According to SVGR recommendations, three plugins mentioned below
(@svgr/plugin-svgo
, @svgr/plugin-jsx
, and @svgr/plugin-prettier
) are used
by default, if you specify no custom SVGR options. The first two of them are
MUST TO HAVE for successful SVG to JSX transformation, thus if you configure
custom plugins, don't foget to include these two explicitly.
Example of options usage:
{
"presets": [
"@babel/env",
"@babel/react",
["@dr.pogodin/babel-preset-svgr", {
"parser": "custom-babel-parser",
"mimicCreateReactApp": true,
"svgr": {
"plugins": [
"@svgr/plugin-svgo",
"@svgr/plugin-jsx",
"@svgr/plugin-prettier"
]
}
}]
]
}
Compatibility with Create React App
Create React App sets up webpack to transform SVG components in the following
way:
- The React component itself is exported as
ReactComponent
named export. - The original SVG path is exported as the default export.
Thus, users import SVG assets like:
import originalPath, { ReactComponent } from './asset.svg';
This preset mimics such behavior when mimicCreateReactApp
option is set:
{
"presets": [
"@babel/env",
"@babel/react",
["@dr.pogodin/babel-preset-svgr", {
"mimicCreateReactApp": true
}]
]
}
By default, originalPath
will be equal to the absolute path of each asset.
In some cases you may want in different, and to cover such cases an object with
additional options can be passed to mimicCreateReactApp
:
module.exports = {
presets: [
'@babel/env',
'@babel/react',
['@dr.pogodin/babel-preset-svgr', {
mimicCreateReactApp: {
pathsRelativeTo: __dirname,
pathsTransform: (path) => `some/prefix/${path}`,
},
}],
],
};
- If
pathsRelativeTo
option is set, originalPath
will be relative to its
value. If pathsRelativeTo
is relative, it is resolved from the current
working directory. - If
pathsTransform
options is set, it should be a function which takes one
argument - the originalPath
, and returns the path that should be output into
the transformed SVG.
Of course, __dirname
and functions can be used only inside JS variation of
Babel config, thus the example above displays .babelrc.js
file, which can be
used instead of .babelrc
starting from Babel@7.