,
el
)
`

You can also use JSON5 notation:

`

`

$3

| Option | Type | Default | Description |
| --------------------------------------- | --------------------- | ---------------------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| name | string | [hash]-[width].[ext] | Filename template for output files. |
| outputPath | string \| Function | undefined | Configure a custom output path for your file |
| publicPath | string \| Function | undefined | Configure a custom public path for your file. |
| context | string | this.options.context | Custom file context, defaults to webpack.config.js context |
| sizes | array | _original size_ | Specify all widths you want to use; if a specified size exceeds the original image's width, the latter will be used (i.e. images won't be scaled up). You may also declare a default sizes array in the loader options in your webpack.config.js. |
| size | integer | _original size_ | Specify one width you want to use; if the specified size exceeds the original image's width, the latter will be used (i.e. images won't be scaled up) |
| min | integer | | As an alternative to manually specifying sizes, you can specify min, max and steps, and the sizes will be generated for you. |
| max | integer | | See min above |
| steps | integer | 4 | Configure the number of images generated between min and max (inclusive) |
| quality | integer | 85 | JPEG and WEBP compression quality |
| format | string | _original format_ | Either png or jpg; use to convert to another format. webp and avif is also supported, but only by the sharp adapter |
| placeholder | boolean | false | A true or false value to specify wether to output a placeholder image as a data URI |
| placeholderSize | integer | 40 | A number value specifying the width of the placeholder image, if enabled with the option above |
| adapter | Adapter | JIMP | Specify which adapter to use. Can only be specified in the loader options. |
| disable | boolean | false | Disable processing of images by this loader (useful in development). srcSet and other attributes will still be generated but only for the original size. Note that the width and height attributes will both be set to 100 but the image will retain its original dimensions. |
| esModule | boolean | false | Use ES modules syntax. |
| emitFile | boolean | true | If true, emits a file (writes a file to the filesystem). If false, the loader will still return a object with the public URI but will not emit the file. It is often useful to disable this option for server-side packages. |
| cacheDirectory | string or boolean | false | Experimental: If true, this will cache the result object but not the image files. The images are only produced once, when they are not found in the results object cache, or when the options change (cache key). For Development you can set query parameter to ?cacheDirectory=false. |

#### Adapter-specific options

##### jimp

- background: number — Background fill when converting transparent to opaque images. Make sure this is a valid hex number, e.g. 0xFFFFFFFF)

##### sharp

- background: string — Background fill when converting transparent to opaque images. E.g. #FFFFFF or %23FFFFFF for webpack > 5
- format: webp — Conversion to the image/webp format. Recognizes the quality option.
- format: avif — Conversion to the image/avif format. Recognizes the quality option.
- progressive: boolean - Use progressive (interlace) scan for image/jpeg format.
- rotate: number - Rotates image more here

$3

Set a default sizes array, so you don't have to declare them with each require.

`js
module.exports = {
entry: {...},
output: {...},
module: {
rules: [
{
test: /\.(jpe?g|png|webp)$/i,
use: [
{
loader: "responsive-loader",
options: {
adapter: require('responsive-loader/sharp'),
sizes: [320, 640, 960, 1200, 1800, 2400],
placeholder: true,
placeholderSize: 20
},
},
],
}
]
},
}
`

$3

Type: Boolean or string
Default: false

Experimental: If true, this will cache the result object but not the image files. The images are only produced once, when they are not found in the results object cache, or when the options change (cache key). For Development you can set query parameter to individual images by using ?cacheDirectory=false.

Default cache directory might be .node_modules/.cache/responsive-loader

`js
module.exports = {
module: {
rules: [
{
test: /\.(jpe?g|png)$/i,
use: [
{
loader: 'responsive-loader',
options: {
esModule: true,
cacheDirectory: true,
publicPath: '/_next',
name: 'static/media/[name]-[hash:7]-[width].[ext]',
},
},
],
},
],
},
}
`

$3

Type: Boolean
Default: false

By default, responsive-loader generates JS modules that use the CommonJS syntax.
There are some cases in which using ES modules is beneficial, like in the case of module concatenation and tree shaking.

You can enable a ES module syntax using:

webpack.config.js

`js
module.exports = {
module: {
rules: [
{
test: /\.(jpe?g|png)$/i,
use: [
{
loader: 'responsive-loader',
options: {
esModule: true,
},
},
],
},
],
},
}
`

$3

Maybe you want to use another image processing library or you want to change an existing one's behavior. You can write your own adapter with the following signature:

`js
type Adapter = (imagePath: string) => {
metadata: () => Promise<{width: number, height: number}>
resize: (config: {width: number, mime: string, options: Object}) => Promise<{data: Buffer, width: number, height: number}>
}
`

The resize method takes a single argument which has a width, mime and options property (which receives all loader options)

In your webpack config, require your adapter

`js
{
test: /\.(jpe?g|png)$/i,
loader: 'responsive-loader',
options: {
adapter: require('./my-adapter')
foo: 'bar' // will get passed to adapter.resize({width, mime, options: {foo: 'bar}})
}
}
`

Notes

- Doesn't support 1x, 2x` sizes, but you probably don't need it.

Usage Examples

$3

- https://github.com/dazuaz/responsive-loader-example

$3

- How to use responsive-loader with Pug. Thanks to the awesome pug-loader.

Please submit your own example to add here

[node]: https://img.shields.io/node/v/responsive-loader.svg
[node-url]: https://nodejs.org
[travis]: https://travis-ci.com/dazuaz/responsive-loader.svg?branch=master
[travis-url]: https://travis-ci.com/dazuaz/responsive-loader