fix: improve imageProxy error handling

apps/backend/src/lib/imageProxy.ts

@@ -11,6 +11,7 @@ const ipx = createIPX({
   storage: ipxFSStorage(),
   httpStorage: ipxHttpStorage({
     allowAllDomains: true,
+    ignoreCacheControl: true,
   }),
 });
 
@@ -28,6 +29,7 @@ export const imageProxyHandler = async (c: Context) => {
       status: 200,
       headers: {
         "x-cache": "HIT",
+        "x-image-proxy": "0.0.1",
         "Content-Type": cachedResponse.type,
         'cache-control': 'max-age=31536000, public, s-maxage=31536000',
       },
@@ -37,12 +39,23 @@ export const imageProxyHandler = async (c: Context) => {
   const response = await createIPXWebServer(ipx)(new Request(targetUrl))
 
   const clonedResponse = response.clone()
-  const data = await clonedResponse.blob()
+  let data = await clonedResponse.blob()
+
+  if (!response.ok) {
+    // Favicons with mimetype 'image/vnd.microsoft.icon' are not supported by IPX / sharp
+    // So we'll fetch it ourselves and cache it
+    const extractedFaviconUrl = targetUrl.match(/\/_\/(https:\/\/.*)/)
+    if (extractedFaviconUrl?.[1]) {
+      const rawFaviconResponse = await fetch(extractedFaviconUrl[1])
+      data = await rawFaviconResponse.blob()
+    }
+  }
 
-  if (response.ok) {
+  if (data.type.match(/^image/)) {
     cache.set(targetUrl, data)
   }
 
+  // TODO: Clone response body from raw retry to immediately return that
   return new Response(response.body, {
     status: response.status,
     statusText: response.statusText