Configure Storybook to work with Next.js, TypeScript, and CSS Modules

README.md

In addition to the Storybook for React setup, you'll also need to install these packages:

npm i -D @babel/core babel-loader css-loader style-loader

main.js

const path = require('path');

module.exports = {
  stories: ['../stories/**/*.stories.js', '../stories/**/*.stories.tsx'],
  addons: ['@storybook/addon-actions', '@storybook/addon-links'],
  presets: [path.resolve(__dirname, './next-preset.js')]
};

next-preset.js

const path = require('path');

module.exports = {
  webpackFinal: async (baseConfig, options) => {
    // Modify or replace config. Mutating the original reference object can cause unexpected bugs.
    const { module = {} } = baseConfig;

    const newConfig = {
      ...baseConfig,
      module: {
        ...module,
        rules: [...(module.rules || [])]
      }
    };

    // TypeScript with Next.js
    newConfig.module.rules.push({
      test: /\.(ts|tsx)$/,
      include: [
        path.resolve(__dirname, '../components'),
        path.resolve(__dirname, '../stories')
      ],
      use: [
        {
          loader: 'babel-loader',
          options: {
            presets: ['next/babel'],
            plugins: ['react-docgen']
          }
        }
      ]
    });
    newConfig.resolve.extensions.push('.ts', '.tsx');

    //
    // CSS Modules
    // Many thanks to https://github.com/storybookjs/storybook/issues/6055#issuecomment-521046352
    //

    // First we prevent webpack from using Storybook CSS rules to process CSS modules
    newConfig.module.rules.find(
      rule => rule.test.toString() === '/\\.css$/'
    ).exclude = /\.module\.css$/;

    // Then we tell webpack what to do with CSS modules
    newConfig.module.rules.push({
      test: /\.module\.css$/,
      include: path.resolve(__dirname, '../components'),
      use: [
        'style-loader',
        {
          loader: 'css-loader',
          options: {
            importLoaders: 1,
            modules: true
          }
        }
      ]
    });

    return newConfig;
  }
};

preview.js

// If you need global CSS, you can import it here and Storybook will automatically include it in all stories.
// You don't need this if you don't have any global CSS.
import '../src/styles.css';

@joebartels - Thank you! - This is the only config I could get to work with SB v6.4, next 11, and SCSS.

@justincy Thank you for your guide!

I made a minimal example using Next.js(v11) + Storybook(v6.3) + CSS Modules.
It works with .module.css and .module.scss.
with-storybook-css-modules-app

It is configured with webpack5 (note: storybook is experimental now).
I'm referring to @joebartels' configuration. Thanks!

// .storybook/main.js
const path = require('path')

module.exports = {
  stories: ['../stories/*.stories.@(ts|tsx|js|jsx|mdx)'],
  addons: ['@storybook/addon-links', '@storybook/addon-essentials'],
  webpackFinal: async (config) => {
    config.module.rules.push({
      test: /\.scss$/,
      use: [
        'style-loader',
        {
          loader: 'css-loader',
          options: {
            modules: {
              auto: true,
            },
          },
        },
        'sass-loader',
      ],
      include: path.resolve(__dirname, '../'),
    })
    return config
  },
  core: {
    builder: 'webpack5',
  },
}

Thank you @joebartels, I've one question left regarding your config. Does your config also support *.module.css files or only *.module.scss. I ran into several issues when trying to work with *.module.scss in my next-scss-tailwind-postcss setup when using modules that do not need to be .scss files necessarily.

FTR: In the end I renamed all my *.module.css files, but I wonder what's happening here. It worked without issues in next itself. 🤷

For those who do not need Sass, I created an example repo with Next.js + Storybook + Tailwind + CSS Module support that does not require to modify the webpackFinal config.

Here is a git diff that focus on the setup.

@tidusia Thanks, your config worked like a charm. I have one question though, why is babel-core and babel-loader needed as mentioned in your diff.

Also, I would like to point out, that if you are using path aliases via typescript, be sure to check this part of the documentation:
https://storybook.js.org/docs/riot/configure/webpack#typescript-module-resolution

you saved my day

Amazing, thank you!