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      • output.inlineStyles

      • Type:
      type InlineChunkTestFunction = (params: {
  size: number;
  name: string;
}) => boolean;

type InlineChunkTest = RegExp | InlineChunkTestFunction;

type InlineChunkConfig =
  | boolean
  | InlineChunkTest
  | { enable?: boolean | 'auto'; test: InlineChunkTest };
      • Default: false

      Whether to inline output style files (.css files) into HTML with <style> tags.

      Only matching stylesheets referenced by the generated HTML are inlined and removed from the output directory. CSS loaded by async chunks remains in separate files.

      Example

      By default, the following output files are generated:

      dist/html/main/index.html
dist/static/css/style.css
dist/static/js/main.js

      After enabling the output.inlineStyles option:

      rsbuild.config.ts
      export default {
  output: {
    inlineStyles: true,
  },
};

      The output files of production build will become:

      dist/html/main/index.html
dist/static/js/main.js

      And dist/static/css/style.css will be inlined in index.html:

      <html>
  <head>
    <style>
      /* content of dist/static/css/style.css */
    </style>
  </head>
  <body></body>
</html>
      Tip

      Setting inlineStyles: true is equivalent to setting inlineStyles.enable to 'auto'. This indicates that inline styles will only be enabled in production mode.

      Using RegExp

      To inline part of the CSS files, set inlineStyles to a regular expression that matches the URL of the CSS file that needs to be inlined.

      For example, to inline main.css into HTML, add the following configuration:

      rsbuild.config.ts
      export default {
  output: {
    inlineStyles: /[\\/]main\.\w+\.css$/,
  },
};
      Tip

      Production filenames include a hash value by default, such as static/css/main.18a568e5ab.css. In regular expressions, use \w+ to match the hash.

      Using function

      Set output.inlineStyles to a function that accepts the following parameters:

      • name: The filename, such as static/css/main.18a568e5ab.css.
      • size: The file size in bytes.

      To inline assets smaller than 10 kB, add the following configuration:

      rsbuild.config.ts
      export default {
  output: {
    inlineStyles({ size }) {
      return size < 10 * 1000;
    },
  },
};

      Options

      enable

      • Type: boolean | 'auto'
      • Default: false

      Whether to enable the inline styles feature. If set to 'auto', it will be enabled when the mode is 'production'.

      rsbuild.config.ts
      export default {
  output: {
    inlineStyles: {
      enable: 'auto',
      test: /[\\/]main\.\w+\.css$/,
    },
  },
};

      test

      • Type: RegExp | ((params: { size: number; name: string }) => boolean)

      The regular expression or function to match the CSS files that need to be inlined.

      rsbuild.config.ts
      export default {
  output: {
    inlineStyles: {
      enable: true,
      test: /[\\/]main\.\w+\.css$/,
    },
  },
};