feat!: migrate to TypeScript and implement emulate using Miniflare

Signed-off-by: Pascal Vorwerk <info@fossores.de>

src/worker.ts

@@ -0,0 +1,75 @@
+import { Server } from "SERVER";
+import { manifest, prerendered, app_path } from "MANIFEST";
+import * as Cache from "worktop/cfw.cache";
+import type { Module } from "worktop/cfw";
+import type { Durable } from "worktop/cfw.durable";
+
+const server = new Server(manifest);
+
+const immutable = `/${app_path}/immutable/`;
+const version_file = `/${app_path}/version.json`;
+
+const worker: Module.Worker<{ ASSETS: Durable.Object }> = {
+	async fetch(req: Request, env, context): Promise<Response> {
+		// @ts-ignore
+		await server.init({ env });
+		// skip cache if "cache-control: no-cache" in request
+		let pragma = req.headers.get("cache-control") || "";
+		let res = !pragma.includes("no-cache") && (await Cache.lookup(req));
+		if (res) return res;
+
+		let { pathname, search } = new URL(req.url);
+		try {
+			pathname = decodeURIComponent(pathname);
+		} catch {
+			// ignore invalid URI
+		}
+
+		const stripped_pathname = pathname.replace(/\/$/, "");
+
+		// prerendered pages and /static files
+		let is_static_asset = false;
+		const filename = stripped_pathname.substring(1);
+		if (filename) {
+			is_static_asset =
+				manifest.assets.has(filename) ||
+				manifest.assets.has(filename + "/index.html");
+		}
+
+		let location =
+			pathname.at(-1) === "/" ? stripped_pathname : pathname + "/";
+
+		if (
+			is_static_asset ||
+			prerendered.has(pathname) ||
+			pathname === version_file ||
+			pathname.startsWith(immutable)
+		) {
+			res = await env.ASSETS.fetch(req);
+		} else if (location && prerendered.has(location)) {
+			if (search) location += search;
+			res = new Response("", {
+				status: 308,
+				headers: {
+					location,
+				},
+			});
+		} else {
+			// dynamically-generated pages
+			res = await server.respond(req, {
+				// @ts-ignore
+				platform: { env, context, caches, cf: req.cf },
+				getClientAddress() {
+					return req.headers.get("cf-connecting-ip")!;
+				},
+			});
+		}
+
+		// write to `Cache` only if response is not an error,
+		// let `Cache.save` handle the Cache-Control and Vary headers
+		pragma = res.headers.get("cache-control") || "";
+		return pragma && res.status < 400 ? Cache.save(req, res, context) : res;
+	},
+};
+
+export default worker;