webpack.prod.js

// webpack.prod.js - production builds
const LEGACY_CONFIG = 'legacy';
const MODERN_CONFIG = 'modern';

// node modules
const git = require('git-rev-sync');
const glob = require('glob-all');
const merge = require('webpack-merge');
const moment = require('moment');
const path = require('path');
const webpack = require('webpack');

// webpack plugins
const BundleAnalyzerPlugin = require('webpack-bundle-analyzer').BundleAnalyzerPlugin;
const { CleanWebpackPlugin } = require('clean-webpack-plugin');
const CompressionPlugin = require('compression-webpack-plugin');
const CreateSymlinkPlugin = require('create-symlink-webpack-plugin');
const CriticalCssPlugin = require('critical-css-webpack-plugin');
const HtmlWebpackPlugin = require('html-webpack-plugin');
const ImageminWebpWebpackPlugin = require('imagemin-webp-webpack-plugin');
const MiniCssExtractPlugin = require('mini-css-extract-plugin');
const OptimizeCSSAssetsPlugin = require('optimize-css-assets-webpack-plugin');
const PurgecssPlugin = require('purgecss-webpack-plugin');
const SaveRemoteFilePlugin = require('save-remote-file-webpack-plugin');
const TerserPlugin = require('terser-webpack-plugin');
const WebappWebpackPlugin = require('webapp-webpack-plugin');
const WhitelisterPlugin = require('purgecss-whitelister');
const WorkboxPlugin = require('workbox-webpack-plugin');
const zopfli = require('@gfx/zopfli');

// config files
const common = require('./webpack.common.js');
const pkg = require('./package.json');
const settings = require('./webpack.settings.js');

// Custom PurgeCSS extractor for Tailwind that allows special characters in
// class names.
//
// https://github.com/FullHuman/purgecss#extractor
class TailwindExtractor {
    static extract(content) {
        return content.match(/[A-Za-z0-9-_:\/]+/g) || [];
    }
}

// Configure file banner
const configureBanner = () => {
    let commitHash = 'n/a';
    let branch = 'n/a';
    try {
        let commitHash = git.long();
        let branch = git.branch();
    } catch(error) {
        console.log('No git repository is associated with this project');
    }
    return {
        banner: [
            '/*!',
            ' * @project        ' + settings.name,
            ' * @name           ' + '[filebase]',
            ' * @author         ' + pkg.author.name,
            ' * @build          ' + moment().format('llll') + ' ET',
            ' * @release        ' + commitHash + ' [' + branch + ']',
            ' * @copyright      Copyright (c) ' + moment().format('YYYY') + ' ' + settings.copyright,
            ' *',
            ' */',
            ''
        ].join('\n'),
        raw: true
    };
};

// Configure Bundle Analyzer
const configureBundleAnalyzer = (buildType) => {
    if (buildType === LEGACY_CONFIG) {
        return {
            analyzerMode: 'static',
            reportFilename: 'report-legacy.html',
        };
    }
    if (buildType === MODERN_CONFIG) {
        return {
            analyzerMode: 'static',
            reportFilename: 'report-modern.html',
        };
    }
};

// Configure Compression webpack plugin
const configureCompression = () => {
    return {
        filename: '[path].gz[query]',
        test: /\.(js|css|html|svg)$/,
        threshold: 10240,
        minRatio: 0.8,
        deleteOriginalAssets: false,
        compressionOptions: {
            numiterations: 15,
            level: 9
        },
        algorithm(input, compressionOptions, callback) {
            return zopfli.gzip(input, compressionOptions, callback);
        }
    };
};

// Configure Critical CSS
const configureCriticalCss = () => {
    return (settings.criticalCssConfig.pages.map((row) => {
            const criticalSrc = settings.urls.critical + row.url;
            const criticalDest = settings.criticalCssConfig.base + row.template + settings.criticalCssConfig.suffix;
            let criticalWidth = settings.criticalCssConfig.criticalWidth;
            let criticalHeight = settings.criticalCssConfig.criticalHeight;
            // Handle Google AMP templates
            if (row.template.indexOf(settings.criticalCssConfig.ampPrefix) !== -1) {
                criticalWidth = settings.criticalCssConfig.ampCriticalWidth;
                criticalHeight = settings.criticalCssConfig.ampCriticalHeight;
            }
            console.log("source: " + criticalSrc + " dest: " + criticalDest);
            return new CriticalCssPlugin({
                base: './',
                src: criticalSrc,
                dest: criticalDest,
                extract: false,
                inline: false,
                minify: true,
                width: criticalWidth,
                height: criticalHeight,
            })
        })
    );
};

// Configure Clean webpack
const configureCleanWebpack = () => {
    return {
        cleanOnceBeforeBuildPatterns: settings.paths.dist.clean,
        verbose: true,
        dry: false
    };
};

// Configure Html webpack
const configureHtml = () => {
    return {
        templateContent: '',
        filename: 'webapp.html',
        inject: false,
    };
};

// Configure Image loader
const configureImageLoader = (buildType) => {
    if (buildType === LEGACY_CONFIG) {
        return {
            test: /\.(png|jpe?g|gif|svg|webp)$/i,
            use: [
                {
                    loader: 'file-loader',
                    options: {
                        name: 'img/[name].[hash].[ext]'
                    }
                }
            ]
        };
    }
    if (buildType === MODERN_CONFIG) {
        return {
            test: /\.(png|jpe?g|gif|svg|webp)$/i,
            use: [
                {
                    loader: 'file-loader',
                    options: {
                        name: 'img/[name].[hash].[ext]'
                    }
                },
                {
                    loader: 'img-loader',
                    options: {
                        plugins: [
                            require('imagemin-gifsicle')({
                                interlaced: true,
                            }),
                            require('imagemin-mozjpeg')({
                                progressive: true,
                                arithmetic: false,
                            }),
                            require('imagemin-optipng')({
                                optimizationLevel: 5,
                            }),
                            require('imagemin-svgo')({
                                plugins: [
                                    {convertPathData: false},
                                ]
                            }),
                        ]
                    }
                }
            ]
        };
    }
};

// Configure optimization
const configureOptimization = (buildType) => {
    if (buildType === LEGACY_CONFIG) {
        return {
            splitChunks: {
                cacheGroups: {
                    default: false,
                    common: false,
                    styles: {
                        name: settings.vars.cssName,
                        test: /\.(pcss|css|vue)$/,
                        chunks: 'all',
                        enforce: true
                    }
                }
            },
            minimizer: [
                new TerserPlugin(
                    configureTerser()
                ),
                new OptimizeCSSAssetsPlugin({
                    cssProcessorOptions: {
                        map: {
                            inline: false,
                            annotation: true,
                        },
                        safe: true,
                        discardComments: true
                    },
                })
            ]
        };
    }
    if (buildType === MODERN_CONFIG) {
        return {
            minimizer: [
                new TerserPlugin(
                    configureTerser()
                ),
            ]
        };
    }
};

// Configure Postcss loader
const configurePostcssLoader = (buildType) => {
    if (buildType === LEGACY_CONFIG) {
        return {
            test: /\.(pcss|css)$/,
            use: [
                MiniCssExtractPlugin.loader,
                {
                    loader: 'css-loader',
                    options: {
                        importLoaders: 2,
                        sourceMap: true
                    }
                },
                {
                    loader: 'resolve-url-loader'
                },
                {
                    loader: 'postcss-loader',
                    options: {
                        sourceMap: true
                    }
                }
            ]
        };
    }
    // Don't generate CSS for the modern config in production
    if (buildType === MODERN_CONFIG) {
        return {
            test: /\.(pcss|css)$/,
            loader: 'ignore-loader'
        };
    }
};

// Configure PurgeCSS
const configurePurgeCss = () => {
    let paths = [];
    // Configure whitelist paths
    for (const [key, value] of Object.entries(settings.purgeCssConfig.paths)) {
        paths.push(path.join(__dirname, value));
    }

    return {
        paths: glob.sync(paths),
        whitelist: WhitelisterPlugin(settings.purgeCssConfig.whitelist),
        whitelistPatterns: settings.purgeCssConfig.whitelistPatterns,
        extractors: [
            {
                extractor: TailwindExtractor,
                extensions: settings.purgeCssConfig.extensions
            }
        ]
    };
};

// Configure terser
const configureTerser = () => {
    return {
        cache: true,
        parallel: true,
        sourceMap: true
    };
};

// Configure Webapp webpack
const configureWebapp = () => {
    return {
        logo: settings.webappConfig.logo,
        prefix: settings.webappConfig.prefix,
        cache: false,
        inject: 'force',
        favicons: {
            appName: pkg.name,
            appDescription: pkg.description,
            developerName: pkg.author.name,
            developerURL: pkg.author.url,
            path: settings.paths.dist.base,
        }
    };
};

// Configure Workbox service worker
const configureWorkbox = () => {
    let config = settings.workboxConfig;

    return config;
};

// Production module exports
module.exports = [
    merge(
        common.legacyConfig,
        {
            output: {
                filename: path.join('./js', '[name]-legacy.[chunkhash].js'),
            },
            mode: 'production',
            devtool: 'source-map',
            optimization: configureOptimization(LEGACY_CONFIG),
            module: {
                rules: [
                    configurePostcssLoader(LEGACY_CONFIG),
                    configureImageLoader(LEGACY_CONFIG),
                ],
            },
            plugins: [
                new MiniCssExtractPlugin({
                    path: path.resolve(__dirname, settings.paths.dist.base),
                    filename: path.join('./css', '[name].[chunkhash].css'),
                }),
                new PurgecssPlugin(
                    configurePurgeCss()
                ),
                new webpack.BannerPlugin(
                    configureBanner()
                ),
                new HtmlWebpackPlugin(
                    configureHtml()
                ),
                new WebappWebpackPlugin(
                    configureWebapp()
                ),
                new CreateSymlinkPlugin(
                    settings.createSymlinkConfig,
                    true
                ),
                new SaveRemoteFilePlugin(
                    settings.saveRemoteFileConfig
                ),
                new CompressionPlugin(
                    configureCompression()
                ),
                new BundleAnalyzerPlugin(
                    configureBundleAnalyzer(LEGACY_CONFIG),
                ),
            ].concat(
                configureCriticalCss()
            )
        }
    ),
    merge(
        common.modernConfig,
        {
            output: {
                filename: path.join('./js', '[name].[chunkhash].js'),
            },
            mode: 'production',
            devtool: 'source-map',
            optimization: configureOptimization(MODERN_CONFIG),
            module: {
                rules: [
                    configurePostcssLoader(MODERN_CONFIG),
                    configureImageLoader(MODERN_CONFIG),
                ],
            },
            plugins: [
                new CleanWebpackPlugin(
                    configureCleanWebpack()
                ),
                new webpack.BannerPlugin(
                    configureBanner()
                ),
                new ImageminWebpWebpackPlugin(),
                new WorkboxPlugin.GenerateSW(
                    configureWorkbox()
                ),
                new CompressionPlugin(
                    configureCompression()
                ),
                new BundleAnalyzerPlugin(
                    configureBundleAnalyzer(MODERN_CONFIG),
                ),
            ]
        }
    ),
];