some code for streamed downloads

1 files changed, 86 insertions, 0 deletions

diff --git a/client-web/source/sw/worker.ts b/client-web/source/sw/worker.ts
new file mode 100644
index 0000000..25f6bab
--- /dev/null
+++ b/client-web/source/sw/worker.ts
@@ -0,0 +1,86 @@
+/*
+    This file is part of keks-meet (https://codeberg.org/metamuffin/keks-meet)
+    which is licensed under the GNU Affero General Public License (version 3); see /COPYING.
+    Copyright (C) 2022 metamuffin <metamuffin@disroot.org>
+*/
+/// <reference no-default-lib="true"/>
+
+/// <reference lib="esnext" />
+/// <reference lib="webworker" />
+declare const self: ServiceWorkerGlobalScope; export { };
+
+console.log("hello from the keks-meet service worker");
+console.log(self.origin)
+
+// let cache: Cache;
+
+self.addEventListener("install", event => {
+    console.log("install");
+    self.skipWaiting()
+    event.waitUntil(caches.delete("v1"))
+})
+self.addEventListener("activate", _event => {
+    console.log("activate");
+    self.clients.claim()
+    // event.waitUntil((async () => {
+    //     cache = await caches.open("v1")
+    //     cache.addAll([
+    //         "/assets/bundle.js",
+    //         "/assets/sw.js",
+    //     ])
+    // })())
+})
+self.addEventListener("unload", () => {
+    console.log("unload")
+})
+
+const streams = new Map<string, { readable: ReadableStream, size: number }>()
+
+self.addEventListener("message", ev => {
+    console.log(ev);
+    const { path, size } = ev.data, port = ev.ports[0]
+    const readable = port_to_readable(port)
+    streams.set(path, { readable, size })
+})
+
+function port_to_readable(port: MessagePort): ReadableStream {
+    return new ReadableStream({
+        start(controller) {
+            console.log("ReadableStream started");
+            port.addEventListener("message", event => {
+                console.log(event.data);
+                if (event.data === "end") { controller.close() }
+                else if (event.data === "abort") controller.error("aborted")
+                else controller.enqueue(event.data)
+            })
+        },
+        cancel() { console.log("ReadableStream cancelled"); port.postMessage({ abort: true }) },
+    })
+}
+
+self.addEventListener("fetch", event => {
+    const { request } = event;
+    if (!request.url.startsWith(self.origin)) return
+    const path = request.url.substring(self.origin.length)
+    console.log(request.method, path);
+
+    const stream = streams.get(path)
+    if (stream) {
+        streams.delete(path)
+        console.log(`-> stream response`);
+        return event.respondWith(
+            new Response(
+                stream.readable,
+                {
+                    headers: new Headers({
+                        "Content-Type": "application/octet-stream; charset=utf-8", // TODO transmit and set accordingly
+                        "Content-Security-Policy": "default-src 'none'",
+                        "Content-Length": `${stream.size}`,
+                    })
+                }
+            )
+        )
+    }
+
+    event.respondWith(fetch(request))
+})