preact.config.js

import CopyWebpackPlugin from 'copy-webpack-plugin';
import swPrecachePlugin from 'preact-cli-sw-precache';
import projectVersion from 'project-version';
import path from 'path';

import swPrecacheConfig from './sw-precache-config';

export default function (config, env, helpers) {
    // Custom sw-precache-config
    swPrecachePlugin(config, swPrecacheConfig);

    // This plugin will copy the necessary WebcomponentsJS files to the build directory
    config.plugins.push(
        new CopyWebpackPlugin([
            {
                from: path.resolve(
                    __dirname,
                    'node_modules/@webcomponents/webcomponentsjs/**/*.js'
                ),
                to: '@webcomponents/webcomponentsjs/[name].[ext]',
            },
        ])
    );

    const API_CONFIG = {
        ACCOUNTS_SERVER: JSON.stringify('http://localhost:81'),

        CLIENT_ID: JSON.stringify('XXX'),
    };

    const definePlugin = helpers.getPluginsByName(config, 'DefinePlugin')[0].plugin;

    definePlugin.definitions = Object.assign(
        definePlugin.definitions,
        Object.assign(
            {
                VERSION: JSON.stringify(projectVersion),
            },
            API_CONFIG
        )
    );
}