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Deno Fetch Event Adapter

Dispatches global fetch events using Deno’s http module native HTTP server.

It is mostly intended as a temporary solution until Deno implements the Service Worker spec directly.

It works fine for local testing, developing Cloudflare Workers while offline, and similar use cases.


import '';

if (typeof FetchEvent !== 'undefined') console.log(true);

self.addEventListener('fetch', event => {
  event.respondWith(new Response('Hello World', { 
    status: 200, 
    headers: [['content-type', 'text/plain']],

Your script needs the --unstable (for native HTTP) and --allow-net permissions. It also requires a --location, to set the port w

deno run --allow-net --location=http://localhost:8000 mod.ts

If you set the --location to either HTTPS or port 443, you have to provide a --cert and a --key parameter. In that case, your script will also need the read permission to read the files:

deno run --allow-net --allow-read --location=https://localhost:8000 mod.ts \
  --cert=./path/to/localhost.key \