Drop CORS for some resource (Deno server)

index.ts

import { Application, Router } from "https://deno.land/x/oak/mod.ts";

const router = new Router();
router.get("/path/:file", async (context) => {
  if (context?.params?.file) {
    const data = await fetch(
      `https://cdn.somedomain.com/js/${context?.params?.file}`,
    );
    console.log(data);
    context.response.body = data.body;
  }
});

const app = new Application();
app.use((ctx, next) => {
  ctx.response.headers.set("Access-Control-Allow-Origin", "*");
  return next();
});
app.use(router.routes());
app.use(router.allowedMethods());

await app.listen({ port: 8000 });