feature: Prerender using webpack

package.json

@@ -73,6 +73,7 @@
   "devDependencies": {
     "babel-cli": "^6.24.0",
     "babel-eslint": "^7.2.1",
+    "babel-plugin-transform-runtime": "^6.23.0",
     "chrome-launcher": "^0.1.1",
     "chrome-remote-interface": "^0.23.2",
     "eslint": "^3.19.0",
@@ -81,6 +82,8 @@
     "html-webpack-exclude-assets-plugin": "0.0.5",
     "lodash": "^4.17.4",
     "ncp": "^2.0.0",
+    "node-sass": "^4.5.3",
+    "sass-loader": "^6.0.6",
     "tap-diff": "^0.1.1",
     "tape": "^4.6.3",
     "uuid": "^3.0.1"
@@ -134,7 +137,7 @@
     "rimraf": "^2.6.1",
     "script-ext-html-webpack-plugin": "^1.8.0",
     "simplehttp2server": "^2.0.0",
-    "sw-precache-webpack-plugin": "^0.11.0",
+    "sw-precache-webpack-plugin": "^0.11.2",
     "tmp": "0.0.31",
     "unfetch": "^3.0.0",
     "url-loader": "^0.5.8",

src/commands/build.js

@@ -2,9 +2,7 @@ import { resolve } from 'path';
 import promisify from 'es6-promisify';
 import rimraf from 'rimraf';
 import asyncCommand from '../lib/async-command';
-import webpackConfig from '../lib/webpack-config';
-import transformConfig from '../lib/transform-config';
-import runWebpack, { showStats, writeJsonStats } from '../lib/run-webpack';
+import runWebpack, { showStats, writeJsonStats } from '../lib/webpack/run-webpack';
 
 export default asyncCommand({
 	command: 'build [src] [dest]',
@@ -47,15 +45,12 @@ export default asyncCommand({
 	},
 
 	async handler(argv) {
-		let config = webpackConfig(argv);
-		await transformConfig(argv, config);
-
 		if (argv.clean) {
 			let dest = resolve(argv.cwd || process.cwd(), argv.dest || 'build');
 			await promisify(rimraf)(dest);
 		}
 
-		let stats = await runWebpack(false, config);
+		let stats = await runWebpack(false, argv);
 		showStats(stats);
 
 		if (argv.json) {

src/commands/watch.js

@@ -1,8 +1,6 @@
 import asyncCommand from '../lib/async-command';
-import webpackConfig from '../lib/webpack-config';
-import transformConfig from '../lib/transform-config';
 import getSslCert from '../lib/ssl-cert';
-import runWebpack, { showStats } from '../lib/run-webpack';
+import runWebpack, { showStats } from '../lib/webpack/run-webpack';
 
 export default asyncCommand({
 	command: 'watch [src]',
@@ -54,10 +52,7 @@ export default asyncCommand({
 			argv.https = ssl;
 		}
 
-		let config = webpackConfig(argv);
-		await transformConfig(argv, config);
-
-		let stats = await runWebpack(true, config, showStats);
+		let stats = await runWebpack(true, argv, showStats);
 		showStats(stats);
 	}
 });

src/lib/async-component-loader.js → src/lib/webpack/async-component-loader.js

@@ -16,7 +16,7 @@ module.exports.pitch = function(remainingRequest) {
 	}
 
 	return `
-		import async from ${JSON.stringify(path.resolve(__dirname, '../components/async'))};
+		import async from ${JSON.stringify(path.resolve(__dirname, '../../components/async'))};
 
 		function load(cb) {
 			require.ensure([], function(require) {

src/lib/webpack/dummy-loader.js

@@ -0,0 +1,3 @@
+module.exports = function(source, map) {
+  this.callback(null, source, map);
+};

src/lib/webpack/prerender.js

@@ -0,0 +1,27 @@
+import { resolve } from 'path';
+
+export default function prerender(outputDir, params) {
+	params = params || {};
+
+	let entry = resolve(outputDir, './ssr-build/ssr-bundle.js'),
+		url = params.url || '/';
+
+	global.location = { href:url, pathname:url };
+	global.history = {};
+
+	let m = require(entry),
+		app = m && m.default || m;
+
+	if (typeof app!=='function') {
+		// eslint-disable-next-line no-console
+		console.warn('Entry does not export a Component function/class, aborting prerendering.');
+		return '';
+	}
+
+	let preact = require('preact'),
+		renderToString = require('preact-render-to-string');
+
+	let html = renderToString(preact.h(app, { url }));
+
+	return html;
+}

src/lib/run-webpack.js → src/lib/webpack/run-webpack.js

@@ -1,25 +1,26 @@
-import { resolve } from 'path';
+import path from 'path';
 import fs from 'fs.promised';
 import webpack from 'webpack';
 import WebpackDevServer from 'webpack-dev-server';
 import chalk from 'chalk';
+import clientConfig from './webpack-client-config';
+import serverConfig from './webpack-server-config';
+import transformConfig from './transform-config';
 
-export default (watch=false, config, onprogress) => new Promise( (resolve, reject) => {
-	let compiler = webpack(config);
+export default async (watch=false, env, onprogress) => {
+	if (watch) {
+		return await devBuild(env, onprogress);
+	}
 
-	let done = (err, stats) => {
-		if (err || stats.hasErrors()) {
-			reject(err || stats.toJson().errors.join('\n'));
-		}
-		else {
-			// Timeout for plugins that work on `after-emit` event of webpack
-			setTimeout(()=>{
-				resolve(stats);
-			},20);
-		}
-	};
+	return await prodBuild(env);
+};
 
-	if (watch) {
+const devBuild = async (env, onprogress) => {
+	let config = clientConfig(env);
+	await transformConfig(env, config);
+
+	let compiler = webpack(config);
+	return await new Promise((resolve, reject) => {
 		let first = true;
 		compiler.plugin('done', stats => {
 			if (first) {
@@ -34,11 +35,34 @@ export default (watch=false, config, onprogress) => new Promise( (resolve, rejec
 
 		let server = new WebpackDevServer(compiler, config.devServer);
 		server.listen(config.devServer.port);
+	});
+};
+
+const prodBuild = async (env) => {
+	let compiler, client = clientConfig(env);
+
+	await transformConfig(env, client);
+
+	if (env.prerender) {
+		let ssrConfig = serverConfig(env);
+		await transformConfig(env, ssrConfig, true);
+		compiler = webpack([client, ssrConfig]);
+	} else {
+		compiler = webpack(client);
 	}
-	else {
-		compiler.run(done);
-	}
-});
+
+	return await new Promise((resolve, reject) => {
+		compiler.run((err, stats) => {
+			if (err || stats.hasErrors()) {
+				reject(err || stats.toJson().errors.join('\n'));
+			}
+			else {
+				// Timeout for plugins that work on `after-emit` event of webpack
+				setTimeout(()=>	resolve(stats), 20);
+			}
+		});
+	});
+};
 
 export function showStats(stats) {
 	let info = stats.toJson();
@@ -59,13 +83,15 @@ export function showStats(stats) {
 }
 
 export function writeJsonStats(stats) {
-	const outputPath = resolve(process.cwd(), 'stats.json');
-	const jsonStats = stats.toJson({
+	let outputPath = path.resolve(process.cwd(), 'stats.json');
+	let jsonStats = stats.toJson({
 		json: true,
 		chunkModules: true,
 		source: false,
 	});
 
+	jsonStats = (jsonStats.children && jsonStats.children[0]) || jsonStats;
+
 	jsonStats.modules.forEach(normalizeModule);
 	jsonStats.chunks.forEach(c => c.modules.forEach(normalizeModule));
 

src/lib/transform-config.js → src/lib/webpack/transform-config.js

@@ -4,7 +4,7 @@ import {
 	webpack,
 } from '@webpack-blocks/webpack2';
 
-export default async function (env, config) {
+export default async function (env, config, ssr = false) {
 	let transformerPath = path.resolve(env.cwd, env.config || './preact.config.js');
 
 	try {
@@ -22,7 +22,7 @@ export default async function (env, config) {
 	const m = require(transformerPath);
 	const transformer = m && m.default || m;
 	try {
-		await transformer(config, Object.assign({}, env), new WebpackConfigHelpers(env.cwd));
+		await transformer(config, Object.assign({}, env, { ssr }), new WebpackConfigHelpers(env.cwd));
 	} catch (err) {
 		throw new Error(`Error at ${transformerPath}: \n` + err);
 	}