chore(cloud-function): send X-Robots-Tag: noindex on pimg (#13503)

* chore(cloud-function): set "X-Robots-Tag: noindex, nofollow" on ad images

* chore(cloud-function): check method on pimg endpoint

* chore(cloud-function): handle failed pimg fetch

Author: caugner

cloud-function/src/handlers/proxy-bsa.ts

@@ -101,18 +101,38 @@ export async function proxyBSA(req: Request, res: Response) {
       console.error(e);
     }
   } else if (pathname.startsWith("/pimg/")) {
+    if (req.method !== "GET") {
+      return res.sendStatus(405).end();
+    }
+
     const src = coder.decodeAndVerify(
       decodeURIComponent(pathname.substring("/pimg/".length))
     );
+
     if (!src) {
+      console.warn("[pimg] Invalid src");
       return res.sendStatus(400).end();
     }
-    const { buf, contentType } = await fetchImage(src);
+
+    const { status, buf, contentType } = await fetchImage(src);
+
+    if (status >= 400) {
+      console.warn(`[pimg] Image fetch failed: HTTP ${status}`);
+      return res
+        .status(status)
+        .set({
+          "cache-control": "no-store",
+          "content-type": contentType,
+        })
+        .end(Buffer.from(buf));
+    }
+
     return res
       .status(200)
       .set({
         "cache-control": "max-age=86400",
         "content-type": contentType,
+        "x-robots-tag": "noindex, nofollow",
       })
       .end(Buffer.from(buf));
   }

libs/pong/image.d.ts

@@ -1,4 +1,5 @@
 export function fetchImage(src: string): Promise<{
+  status: number;
   buf: ArrayBuffer;
   contentType: string;
 }>;

libs/pong/image.js

@@ -1,7 +1,8 @@
 /* global fetch */
 export async function fetchImage(src) {
-  const imageResponse = await fetch(src);
-  const imageBuffer = await imageResponse.arrayBuffer();
-  const contentType = imageResponse.headers.get("content-type");
-  return { buf: imageBuffer, contentType };
+  const res = await fetch(src);
+  const status = res.status;
+  const buf = await res.arrayBuffer();
+  const contentType = res.headers.get("content-type");
+  return { status, buf, contentType };
 }