refactor: remove Val Town references and update exit node documentation

apps_script/valtown.ts

@@ -1,88 +0,0 @@
-const PSK = "CHANGE_ME_TO_A_STRONG_SECRET";
-
-const STRIP_HEADERS = new Set([
-  "host",
-  "connection",
-  "content-length",
-  "transfer-encoding",
-  "proxy-connection",
-  "proxy-authorization",
-  "x-forwarded-for",
-  "x-forwarded-host",
-  "x-forwarded-proto",
-  "x-forwarded-port",
-  "x-real-ip",
-  "forwarded",
-  "via",
-]);
-
-function decodeBase64ToBytes(input: string): Uint8Array {
-  const bin = atob(input);
-  const out = new Uint8Array(bin.length);
-  for (let i = 0; i < bin.length; i++) out[i] = bin.charCodeAt(i);
-  return out;
-}
-
-function encodeBytesToBase64(bytes: Uint8Array): string {
-  let bin = "";
-  for (let i = 0; i < bytes.length; i++) bin += String.fromCharCode(bytes[i]);
-  return btoa(bin);
-}
-
-function sanitizeHeaders(h: unknown): Record<string, string> {
-  const out: Record<string, string> = {};
-  if (!h || typeof h !== "object") return out;
-  for (const [k, v] of Object.entries(h as Record<string, unknown>)) {
-    if (!k) continue;
-    if (STRIP_HEADERS.has(k.toLowerCase())) continue;
-    out[k] = String(v ?? "");
-  }
-  return out;
-}
-
-export default async function(req: Request): Promise<Response> {
-  try {
-    if (req.method !== "POST") {
-      return Response.json({ e: "method_not_allowed" }, { status: 405 });
-    }
-
-    const body = await req.json();
-    if (!body || typeof body !== "object") {
-      return Response.json({ e: "bad_json" }, { status: 400 });
-    }
-
-    const k = String((body as any).k ?? "");
-    const u = String((body as any).u ?? "");
-    const m = String((body as any).m ?? "GET").toUpperCase();
-    const h = sanitizeHeaders((body as any).h);
-    const b64 = (body as any).b;
-
-    if (k !== PSK) return Response.json({ e: "unauthorized" }, { status: 401 });
-    if (!/^https?:\/\//i.test(u)) return Response.json({ e: "bad url" }, { status: 400 });
-
-    let payload: Uint8Array | undefined;
-    if (typeof b64 === "string" && b64.length > 0) payload = decodeBase64ToBytes(b64);
-
-    const resp = await fetch(u, {
-      method: m,
-      headers: h,
-      body: payload,
-      redirect: "manual",
-    });
-
-    const data = new Uint8Array(await resp.arrayBuffer());
-    const respHeaders: Record<string, string> = {};
-    resp.headers.forEach((value, key) => {
-      respHeaders[key] = value;
-    });
-
-    return Response.json({
-      s: resp.status,
-      h: respHeaders,
-      b: encodeBytesToBase64(data),
-    });
-  } catch (err) {
-    const message = err instanceof Error ? err.message : String(err);
-    return Response.json({ e: message }, { status: 500 });
-  }
-}