Embed workers into index

scripts/minifyJs.js

@@ -14,6 +14,30 @@ const JS_MINIFIER_CONFIG = {
   sourceMap: false,
 };
 
+const workerRegEx =
+  /new Worker\(\w+\.\w+\(new URL\(\w+\.\w+\+\w+\.\w+\(\d+\),\w+\.\w+\)\),\{name:"(\w+)"\}\)/;
+
+const inlineIndexWorkers = (code) => {
+  const [, workerName] = code.match(workerRegEx) || [];
+
+  if (workerName) {
+    const workerFilename = readdirSync(
+      join(OUT_PATH, "_next/static/chunks")
+    ).find((entry) => entry.startsWith(`${workerName}.`));
+    const workerSource = readFileSync(
+      join(OUT_PATH, "_next/static/chunks", workerFilename)
+    );
+    const base64Worker = Buffer.from(workerSource).toString("base64");
+
+    return code.replace(
+      workerRegEx,
+      `new Worker("data:application/javascript;base64,${base64Worker}",{name:"${workerName}"})`
+    );
+  }
+
+  return code;
+};
+
 const minifyJsFiles = (path) =>
   Promise.all(
     readdirSync(path).map(async (entry) => {
@@ -24,12 +48,22 @@ const minifyJsFiles = (path) =>
         minifyJsFiles(fullPath);
       } else if (extname(entry).toLowerCase() === ".js") {
         const js = readFileSync(fullPath);
-        const { code: minifiedJs, error } = await minify(
+        let { code: minifiedJs, error } = await minify(
           js.toString(),
           JS_MINIFIER_CONFIG
         );
 
         if (!error && minifiedJs?.length > 0) {
+          if (entry.startsWith("index-")) {
+            const changedCode = inlineIndexWorkers(minifiedJs);
+
+            if (minifiedJs === changedCode) {
+              throw new Error("Inlining worker failed!");
+            }
+
+            minifiedJs = changedCode;
+          }
+
           writeFileSync(fullPath, minifiedJs);
         }
       }