feat: add production entry & template

lib/core/prodEntry.js

@@ -0,0 +1,34 @@
+import React from 'react';
+import {BrowserRouter, StaticRouter} from 'react-router-dom';
+import ReactDOM from 'react-dom';
+import ReactDOMServer from 'react-dom/server';
+
+import App from './App';
+import createHtml from './prodTemplate';
+
+// Client side render (e.g: running in browser) to become single-page application (SPA)
+if (typeof document !== 'undefined') {
+  ReactDOM.render(
+    <BrowserRouter>
+      <App />
+    </BrowserRouter>,
+    document.getElementById('app')
+  );
+}
+
+// Renderer for static-site-generator-webpack-plugin (async rendering via callbacks)
+export default function render(locals, callback) {
+  const context = {};
+  const body = ReactDOMServer.renderToString(
+    <StaticRouter location={locals.path} context={context}>
+      <App />
+    </StaticRouter>
+  );
+  const html = createHtml({
+    title: locals.title,
+    body,
+    bundlejs: locals.bundlejs,
+    lang: locals.lang
+  });
+  callback(null, html);
+}