cf-dl.js

// A cloudflare worker that just proxies data from somewhere to you
// Credits to https://github.com/TheGreatAzizi/GitHub-High-Speed-Mirror
export default {
  async fetch(request, env, ctx) {
    // Parse the URL
    const url = new URL(request.url);
    const params = new URLSearchParams(url.search);
    if (!params.has("url")) return new Response("Invalid URL", { status: 400 });
    const target = params.get("url");

    // Request the URL
    const upstreamReq = new Request(target, {
      method: request.method,
      headers: {
        "User-Agent": "CF-Proxy",
        "Range": request.headers.get("Range") || ""
      },
      redirect: "follow"
    });
    const upstreamRes = await fetch(upstreamReq);

    // Stream back data
    const headers = new Headers(upstreamRes.headers);
    headers.set("Access-Control-Allow-Origin", "*");
    headers.set("X-Worker-Cache", "MISS");
    headers.set(
      "Content-Disposition",
      `attachment; filename="${getFilename(target, upstreamRes)}"`
    );

    return new Response(upstreamRes.body, {
      status: upstreamRes.status,
      headers
    });
  }
};

function getFilename(url, res) {
  const cd = res.headers.get("content-disposition");
  if (cd) {
    const m = cd.match(/filename="?([^"]+)"?/i);
    if (m) return m[1];
  }
  return url.split("/").pop() || "download";
}