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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.

Example

// filename: "sw.js"
import 'https://deno.land/x/fetch_event_adapter/listen.ts';

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

self.addEventListener('fetch', event => {
  const ip = event.request.headers.get("x-forwarded-for");
  event.respondWith(new Response(`Hello ${ip}`, { 
    headers: [['content-type', 'text/plain']],
  }));
});

Your script needs the --allow-net permissions. It also requires a --location, to know on which port to listen for incoming connections:

deno run --allow-net --location=http://localhost:8000 sw.js

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

deno run --allow-net --allow-read --location=https://localhost:8000 sw.js \
  --cert=./path/to/localhost.crt \
  --key=./path/to/localhost.key