svelte-preprocess-import-assets

svelte-preprocess-import-assets

Import assets directly in the markup. Supports Svelte 3, 4, and 5.

NOTE: Svelte 5 support is experimental and may break between versions.

Convert this:

<h1>Look at this image</h1>
<img src="./assets/cool-image.png" alt="cool image" />

Into this:

<script>
  import ___ASSET___0 from './assets/cool-image.png'
</script>

<h1>Look at this image</h1>
<img src={___ASSET___0} alt="cool image" />

Usage

Install with your package manager:

npm install --save-dev svelte-preprocess-import-assets

Include the preprocessor in your bundler's Svelte plugin preprocess option:

import { importAssets } from 'svelte-preprocess-import-assets'

svelte({ preprocess: [importAssets()] })

// or in svelte.config.js
export default {
  preprocess: [importAssets()],
  // ... other svelte options
}

API

The importAssets() function receives an optional options object for its first parameter. The object may contain these properties:

sources

• Type: AssetSource[] | ((defaultSources: AssetSource[]) => AssetSource[])

  interface AssetSource {
    tag: string
    srcAttributes?: string[]
    srcsetAttributes?: string[]
    filter?: (metadata: FilterMetadata) => boolean
  }
  
  interface FilterMetadata {
    tag: string
    attribute: string
    value: string
    attributes: Record<string, string>
  }
  

• Default: See DEFAULT_SOURCES in src/constants.js

  These are the sources to look for when scanning for imports. You can provide an entirely different list of sources, or declare a function to access the default sources and augment it. The supported tags and attributes are based on html-loader (except icon-uri). Component name as tag is also supported.

  {
    sources: (defaultSources) => {
      return [
        ...defaultSources,
        // Also scan `data-src` and `data-srcset` of an img tag
        {
          tag: 'img',
          srcAttributes: ['data-src'],
          srcsetAttributes: ['data-srcset'],
        },
      ]
    },
  }
  

importPrefix

• Type: string

• Default: ___ASSET___

  The string to be prefixed for asset import names, e.g. ___ASSET___0 and ___ASSET___1.

http

• Type: boolean

• Default: false

  Whether a URL with http/https protocol should be converted to an import.

urlFilter

• Type: (url: string) => boolean

  Whether a URL should be converted into an import.

  {
    // Include URLs with specific extensions only
    urlFilter: (url) => /\.(png|jpg|gif|webp)$/.test(url),
  }
  

Recipes

Ignore an element

<!-- svelte-preprocess-import-assets-ignore -->
<img src="./assets/cool-image.png" alt="cool image" />

Attributions

• svelte-assets-preprocessor: Initial motivation to reduce dependencies.

Sponsors

License

MIT

Changelog

1.1.0 - 2023-11-11

• Support Svelte 5
• Add estree-walker as dependency to support Svelte 5