Function fetch

serverless/cloudflare/src/index.ts:92–223

(
    request: Request,
    env: Env,
    ctx: ExecutionContext
  )

export default {
  async fetch(
    request: Request,
    env: Env,
    ctx: ExecutionContext
  ): Promise<Response> {
    if (request.method.toUpperCase() === "POST")
      return new Response(undefined, { status: 405 });

    const url = new URL(request.url);
    const { ok, name, tile, ext } = tile_path(url.pathname);

    const cache = caches.default;

    if (!ok) {
      return new Response("Invalid URL", { status: 404 });
    }

    let allowedOrigin = "";
    if (typeof env.ALLOWED_ORIGINS !== "undefined") {
      for (const o of env.ALLOWED_ORIGINS.split(",")) {
        if (o === request.headers.get("Origin") || o === "*") {
          allowedOrigin = o;
        }
      }
    }

    const cached = await cache.match(request.url);
    if (cached) {
      const respHeaders = new Headers(cached.headers);
      if (allowedOrigin)
        respHeaders.set("Access-Control-Allow-Origin", allowedOrigin);
      respHeaders.set("Vary", "Origin");

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

    const cacheableResponse = (
      body: ArrayBuffer | string | undefined,
      cacheableHeaders: Headers,
      status: number
    ) => {
      cacheableHeaders.set(
        "Cache-Control",
        env.CACHE_CONTROL || "public, max-age=86400"
      );

      const cacheable = new Response(body, {
        headers: cacheableHeaders,
        status: status,
      });

      ctx.waitUntil(cache.put(request.url, cacheable));

      const respHeaders = new Headers(cacheableHeaders);
      if (allowedOrigin)