GoScrobble/web/node_modules/url-loader/README.md

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<a href="https://github.com/webpack/webpack">
<img width="200" height="200" src="https://webpack.js.org/assets/icon-square-big.svg">
</a>
</div>
[![npm][npm]][npm-url]
[![node][node]][node-url]
[![deps][deps]][deps-url]
[![tests][tests]][tests-url]
[![chat][chat]][chat-url]
[![size][size]][size-url]
# url-loader
A loader for webpack which transforms files into base64 URIs.
## Getting Started
To begin, you'll need to install `url-loader`:
```console
$ npm install url-loader --save-dev
```
`url-loader` works like
[`file-loader`](https://github.com/webpack-contrib/file-loader), but can return
a DataURL if the file is smaller than a byte limit.
**index.js**
```js
import img from './image.png';
```
**webpack.config.js**
```js
module.exports = {
module: {
rules: [
{
test: /\.(png|jpg|gif)$/i,
use: [
{
loader: 'url-loader',
options: {
limit: 8192,
},
},
],
},
],
},
};
```
And run `webpack` via your preferred method.
## Options
| Name | Type | Default | Description |
| :---------------------------: | :-------------------------: | :-----------------------------------------------------------: | :---------------------------------------------------------------------------------- |
| **[`limit`](#limit)** | `{Boolean\|Number\|String}` | `true` | Specifying the maximum size of a file in bytes. |
| **[`mimetype`](#mimetype)** | `{Boolean\|String}` | based from [mime-types](https://github.com/jshttp/mime-types) | Sets the MIME type for the file to be transformed. |
| **[`encoding`](#encoding)** | `{Boolean\|String}` | `base64` | Specify the encoding which the file will be inlined with. |
| **[`generator`](#generator)** | `{Function}` | `() => type/subtype;encoding,base64_data` | You can create you own custom implementation for encoding data. |
| **[`fallback`](#fallback)** | `{String}` | `file-loader` | Specifies an alternative loader to use when a target file's size exceeds the limit. |
| **[`esModule`](#esmodule)** | `{Boolean}` | `true` | Use ES modules syntax. |
### `limit`
Type: `Boolean|Number|String`
Default: `undefined`
The limit can be specified via loader options and defaults to no limit.
#### `Boolean`
Enable or disable transform files into base64.
**webpack.config.js**
```js
module.exports = {
module: {
rules: [
{
test: /\.(png|jpg|gif)$/i,
use: [
{
loader: 'url-loader',
options: {
limit: false,
},
},
],
},
],
},
};
```
#### `Number|String`
A `Number` or `String` specifying the maximum size of a file in bytes.
If the file size is **equal** or **greater** than the limit [`file-loader`](https://github.com/webpack-contrib/file-loader) will be used (by default) and all query parameters are passed to it.
Using an alternative to `file-loader` is enabled via the `fallback` option.
**webpack.config.js**
```js
module.exports = {
module: {
rules: [
{
test: /\.(png|jpg|gif)$/i,
use: [
{
loader: 'url-loader',
options: {
limit: 8192,
},
},
],
},
],
},
};
```
### `mimetype`
Type: `Boolean|String`
Default: based from [mime-types](https://github.com/jshttp/mime-types)
Specify the `mimetype` which the file will be inlined with.
If unspecified the `mimetype` value will be used from [mime-types](https://github.com/jshttp/mime-types).
#### `Boolean`
The `true` value allows to generation the `mimetype` part from [mime-types](https://github.com/jshttp/mime-types).
The `false` value removes the `mediatype` part from a Data URL (if omitted, defaults to `text/plain;charset=US-ASCII`).
**webpack.config.js**
```js
module.exports = {
module: {
rules: [
{
test: /\.(png|jpg|gif)$/i,
use: [
{
loader: 'url-loader',
options: {
mimetype: false,
},
},
],
},
],
},
};
```
#### `String`
Sets the MIME type for the file to be transformed.
**webpack.config.js**
```js
module.exports = {
module: {
rules: [
{
test: /\.(png|jpg|gif)$/i,
use: [
{
loader: 'url-loader',
options: {
mimetype: 'image/png',
},
},
],
},
],
},
};
```
### `encoding`
Type: `Boolean|String`
Default: `base64`
Specify the `encoding` which the file will be inlined with.
If unspecified the `encoding` will be `base64`.
#### `Boolean`
If you don't want to use any encoding you can set `encoding` to `false` however if you set it to `true` it will use the default encoding `base64`.
**webpack.config.js**
```js
module.exports = {
module: {
rules: [
{
test: /\.svg$/i,
use: [
{
loader: 'url-loader',
options: {
encoding: false,
},
},
],
},
],
},
};
```
#### `String`
It supports [Node.js Buffers and Character Encodings](https://nodejs.org/api/buffer.html#buffer_buffers_and_character_encodings) which are `["utf8","utf16le","latin1","base64","hex","ascii","binary","ucs2"]`.
**webpack.config.js**
```js
module.exports = {
module: {
rules: [
{
test: /\.svg$/i,
use: [
{
loader: 'url-loader',
options: {
encoding: 'utf8',
},
},
],
},
],
},
};
```
### `generator`
Type: `Function`
Default: `(mimetype, encoding, content, resourcePath) => mimetype;encoding,base64_content`
You can create you own custom implementation for encoding data.
**webpack.config.js**
```js
module.exports = {
module: {
rules: [
{
test: /\.(png|html)$/i,
use: [
{
loader: 'url-loader',
options: {
// The `mimetype` and `encoding` arguments will be obtained from your options
// The `resourcePath` argument is path to file.
generator: (content, mimetype, encoding, resourcePath) => {
if (/\.html$/i.test(resourcePath)) {
return `data:${mimetype},${content.toString()}`;
}
return `data:${mimetype}${
encoding ? `;${encoding}` : ''
},${content.toString(encoding)}`;
},
},
},
],
},
],
},
};
```
### `fallback`
Type: `String`
Default: `'file-loader'`
Specifies an alternative loader to use when a target file's size exceeds the limit set in the `limit` option.
**webpack.config.js**
```js
module.exports = {
module: {
rules: [
{
test: /\.(png|jpg|gif)$/i,
use: [
{
loader: 'url-loader',
options: {
fallback: require.resolve('responsive-loader'),
},
},
],
},
],
},
};
```
The fallback loader will receive the same configuration options as url-loader.
For example, to set the quality option of a responsive-loader above use:
**webpack.config.js**
```js
module.exports = {
module: {
rules: [
{
test: /\.(png|jpg|gif)$/i,
use: [
{
loader: 'url-loader',
options: {
fallback: require.resolve('responsive-loader'),
quality: 85,
},
},
],
},
],
},
};
```
### `esModule`
Type: `Boolean`
Default: `true`
By default, `file-loader` generates JS modules that use the ES modules syntax.
There are some cases in which using ES modules is beneficial, like in the case of [module concatenation](https://webpack.js.org/plugins/module-concatenation-plugin/) and [tree shaking](https://webpack.js.org/guides/tree-shaking/).
You can enable a CommonJS module syntax using:
**webpack.config.js**
```js
module.exports = {
module: {
rules: [
{
test: /\.css$/,
use: [
{
loader: 'url-loader',
options: {
esModule: false,
},
},
],
},
],
},
};
```
## Examples
### SVG
SVG can be compressed into a more compact output, avoiding `base64`.
You can read about it more [here](https://css-tricks.com/probably-dont-base64-svg/).
You can do it using [mini-svg-data-uri](https://github.com/tigt/mini-svg-data-uri) package.
**webpack.config.js**
```js
const svgToMiniDataURI = require('mini-svg-data-uri');
module.exports = {
module: {
rules: [
{
test: /\.svg$/i,
use: [
{
loader: 'url-loader',
options: {
generator: (content) => svgToMiniDataURI(content.toString()),
},
},
],
},
],
},
};
```
## Contributing
Please take a moment to read our contributing guidelines if you haven't yet done so.
[CONTRIBUTING](./.github/CONTRIBUTING.md)
## License
[MIT](./LICENSE)
[npm]: https://img.shields.io/npm/v/url-loader.svg
[npm-url]: https://npmjs.com/package/url-loader
[node]: https://img.shields.io/node/v/url-loader.svg
[node-url]: https://nodejs.org
[deps]: https://david-dm.org/webpack-contrib/url-loader.svg
[deps-url]: https://david-dm.org/webpack-contrib/url-loader
[tests]: https://github.com/webpack-contrib/url-loader/workflows/url-loader/badge.svg
[tests-url]: https://github.com/webpack-contrib/url-loader/actions
[cover]: https://codecov.io/gh/webpack-contrib/url-loader/branch/master/graph/badge.svg
[cover-url]: https://codecov.io/gh/webpack-contrib/url-loader
[chat]: https://img.shields.io/badge/gitter-webpack%2Fwebpack-brightgreen.svg
[chat-url]: https://gitter.im/webpack/webpack
[size]: https://packagephobia.now.sh/badge?p=url-loader
[size-url]: https://packagephobia.now.sh/result?p=url-loader
```
```