Move middleware utils into server/utils

server/utils/createBundle.js

@@ -0,0 +1,45 @@
+/**
+ * Creates a bundle object that is stored on req.bundle.
+ */
+function createBundle(webpackStats) {
+  const { publicPath, assetsByChunkName } = webpackStats;
+
+  /**
+   * Returns a public URL to the given asset.
+   */
+  function createURL(asset) {
+    return publicPath + asset;
+  }
+
+  /**
+   * Returns an array of URLs to all assets in the given chunks.
+   */
+  function getAssets(chunks = ["main"]) {
+    return (Array.isArray(chunks) ? chunks : [chunks])
+      .reduce((memo, chunk) => memo.concat(assetsByChunkName[chunk] || []), [])
+      .map(createURL);
+  }
+
+  /**
+   * Returns an array of URLs to all JavaScript files in the given chunks.
+   */
+  function getScripts(...chunks) {
+    return getAssets(...chunks).filter(asset => /\.js$/.test(asset));
+  }
+
+  /**
+   * Returns an array of URLs to all CSS files in the given chunks.
+   */
+  function getStyles(...chunks) {
+    return getAssets(...chunks).filter(asset => /\.css$/.test(asset));
+  }
+
+  return {
+    createURL,
+    getAssets,
+    getScripts,
+    getStyles
+  };
+}
+
+module.exports = createBundle;