Add hello world cf function

functions/hello-world.js

@@ -0,0 +1,13 @@
+export async function onRequest(context) {
+    // Contents of context object
+    const {
+        request, // same as existing Worker API
+        env, // same as existing Worker API
+        params, // if filename includes [id] or [[path]]
+        waitUntil, // same as ctx.waitUntil in existing Worker API
+        next, // used for middleware or to fetch assets
+        data, // arbitrary space for passing data between middlewares
+    } = context;
+
+    return new Response('Hello, worker!')
+}