How do I import all CSS files ins subdirectory with webpack / postcss @import '../Components/**/_partial.css';

Question

Using a Webpack and PostCSS environment I would like to import all CSS files in my Components folder and the subdirectory. I've tried both PostCSS plugins postcss-easy-import & postcss-import and know they both need to come first. Regular Imports with direct paths work, could it be that ** placeholders don't work?

Thanks in advance

Answer 1

The best practice to import css or scss files is importing all your css files or components in one main.css or scss file. Then import that file in your entry *.js file and finally set that *.js file in your webpack config file as an entry.

For example if you have a folder called SampleProject and a folder and file structure like this:

SampleProject
|
|--css
|  |--components
|  |  |--style1.css
|  |  |--style2.css
|  |  |--style3.css
|
|--js
|  |--components
|  |  |--script1.js
|  |  |--script2.js
|
main.css
index.js
index.html
webpack.prod.js
package.json

Then you can import all you 3 style files in your main.css file like below:

main.css

@import 'css/components/style1.css';
@import 'css/components/style2.css';
@import 'css/components/style3.css';

Then you can import the main.css file into index.js with other js chunks like this:

index.js

import './main.css';
import 'js/components/script1.js';
import 'js/components/script2.js';

Finally, you can use this index.js as an entry point into your webpack config file like this:

webpack.prod.js:

const webpack = require('webpack');
const path = require('path');
const MiniCssExtractPlugin = require('mini-css-extract-plugin');
const HtmlWebpackPlugin = require('html-webpack-plugin');
const { CleanWebpackPlugin } = require('clean-webpack-plugin');
const TerserJSPlugin = require('terser-webpack-plugin');
const OptimizeCSSAssetsPlugin = require('optimize-css-assets-webpack-plugin');

module.exports = {
  entry: {
    main: './index.js'
  },
  output: {
    path: path.join(__dirname, './build'), 
    filename: '[name].[chunkhash:8].bundle.js',
    chunkFilename: '[name].[chunkhash:8].chunk.js',
  },
  mode: 'production',
  module: {
    rules: [
      {
        test: /\.js$/,
        exclude: /node_modules/,
        use: {
          loader: 'babel-loader', 
        },
      },
      {
        test: /\.(sa|sc|c)ss$/,
        use: [
          MiniCssExtractPlugin.loader,
          'css-loader', 
          'postcss-loader', 
          //'sass-loader',
        ],
      },
      {
        test: /\.(png|svg|jpe?g|gif)$/i,
        use: [
          {
            loader: 'file-loader', 
            options: {
              name: '[name].[ext]',
              outputPath: 'assets/img',
              esModule: false,
            },
          },
        ],
      },
      {
        test: /\.(woff|woff2|eot|ttf|otf)$/,
        use: [
          {
            loader: 'file-loader', 
            options: {
              name: '[name].[ext]',
              outputPath: 'assets/font',
            },
          },
        ],
      },
      {
        test: /\.html$/i,
        use: {
          loader: 'html-loader',
          options: {
            attributes: {
              list: [
                {
                  tag: 'img',
                  attribute: 'src',
                  type: 'src',
                },
                {
                  tag: 'img',
                  attribute: 'srcset',
                  type: 'srcset',
                },
                {
                  tag: 'img',
                  attribute: 'data-src',
                  type: 'src',
                },
                {
                  tag: 'img',
                  attribute: 'data-srcset',
                  type: 'srcset',
                },
              ],

            },
          },
        },
      },
    ],
  },
  optimization: {
    minimizer: [new TerserJSPlugin(), new OptimizeCSSAssetsPlugin()],
    splitChunks: {
      cacheGroups: {
        commons: {
          test: /[\\/]node_modules[\\/]/,
          name: 'vendors',
          chunks: 'all',
        },
      },
      chunks: 'all',
    },
    runtimeChunk: {
      name: 'runtime',
    },
  },
  plugins: [
    // load jQuery
    new webpack.ProvidePlugin({
      $: 'jquery',
      jQuery: 'jquery',
    }),

    new CleanWebpackPlugin(),

    new MiniCssExtractPlugin({
      filename: '[name].[chunkhash:8].bundle.css',
      chunkFilename: '[name].[chunkhash:8].chunk.css',
    }),

    new HtmlWebpackPlugin({
      chunks: ['main'],
      template: 'index.html',
      filename: 'index.html',
    }),

  ],
};

And MiniCssExtractPlugin will extract all styles of your project automatically and save them as one file in build folder in root of your project.