fixup! fix(http): correctly cache blob responses in transfer cache

Previously, Blob values were passed to `Uint8Array` this resulted in silently producing an empty array (length = 0) without throwing an error, leading to empty cached data
angular · SkyZeroZx · Feb 11, 2026 · Feb 12, 2026 · Feb 13, 2026 · Feb 18, 2026
commit 6a0a9ed0b57c734f222f1d99081fb7675ddd02b6
diff --git a/packages/common/http/src/transfer_cache.ts b/packages/common/http/src/transfer_cache.ts
@@ -20,8 +20,8 @@ import {
   ɵtruncateMiddle as truncateMiddle,
   ɵRuntimeError as RuntimeError,
 } from '@angular/core';
-import {Observable, of, from} from 'rxjs';
-import {tap, concatMap} from 'rxjs/operators';
+import {Observable, of} from 'rxjs';
+import {concatMap} from 'rxjs/operators';
 
 import {RuntimeErrorCode} from './errors';
 import {HttpHeaders} from './headers';
@@ -266,41 +266,32 @@ export function transferCacheInterceptorFn(
   if (typeof ngServerMode !== 'undefined' && ngServerMode) {
     // Request not found in cache. Make the request and cache it if on the server.
     return event$.pipe(
-      concatMap((event: HttpEvent<unknown>) => {
+      concatMap(async (event: HttpEvent<unknown>) => {
         // Only cache successful HTTP responses.
         if (event instanceof HttpResponse) {
-          const storeInCache = (body: unknown) => {
-            transferState.set<TransferHttpResponse>(storeKey, {
-              [BODY]: body,
-              [HEADERS]: getFilteredHeaders(event.headers, headersToInclude),
-              [STATUS]: event.status,
-              [STATUS_TEXT]: event.statusText,
-              [REQ_URL]: requestUrl,
-              [RESPONSE_TYPE]: req.responseType,
-            });
-          };
-
+          let body = event.body;
           if (req.responseType === 'blob') {
-            // Convert Blob to ArrayBuffer asynchronously before caching.
             // Note: Blob is converted to ArrayBuffer because Uint8Array constructor
             // doesn't accept Blob directly, which would result in an empty array.
             // Type assertion is safe here: when responseType is 'blob', the body is guaranteed to be a Blob
-            return from((event.body as Blob).arrayBuffer()).pipe(
-              tap((arrayBuffer) => storeInCache(toBase64(arrayBuffer))),
-              concatMap(() => of(event)),
-            );
+            const arrayBuffer = await (event.body as Blob).arrayBuffer();
+            body = toBase64(arrayBuffer);
+          } else if (req.responseType === 'arraybuffer') {
+            // For arraybuffer, convert to base64; for other types (json, text), store as-is.
+            // Type assertion is safe here: when responseType is 'arraybuffer', the body is
+            // guaranteed to be an ArrayBuffer
+            body = toBase64(event.body as ArrayBufferLike);
           }
-
-          // For arraybuffer, convert to base64; for other types (json, text), store as-is.
-          // Type assertion is safe here: when responseType is 'arraybuffer', the body is
-          // guaranteed to be an ArrayBuffer
-          const body =
-            req.responseType === 'arraybuffer'
-              ? toBase64(event.body as ArrayBufferLike)
-              : event.body;
-          storeInCache(body);
+          transferState.set<TransferHttpResponse>(storeKey, {
+            [BODY]: body,
+            [HEADERS]: getFilteredHeaders(event.headers, headersToInclude),
+            [STATUS]: event.status,
+            [STATUS_TEXT]: event.statusText,
+            [REQ_URL]: requestUrl,
+            [RESPONSE_TYPE]: req.responseType,
+          });
         }
-        return of(event);
+        return event;
       }),
     );
   }