Update

Services/S3StorageService.cs

@@ -33,9 +33,11 @@ public sealed class S3StorageService(IAmazonS3 s3) : IStorageService
                 BucketName = bucket,
                 ContinuationToken = token
             }, ct);
-
-            items.AddRange(resp.S3Objects.Select(o => new ObjectItem(o.Key, o.Size, o.LastModified)));
-            token = (bool)resp.IsTruncated ? resp.NextContinuationToken : null;
+            if (resp.S3Objects != null)
+            {
+                items.AddRange(resp.S3Objects.Select(o => new ObjectItem(o.Key, o.Size, o.LastModified)));
+                token = (bool)resp.IsTruncated ? resp.NextContinuationToken : null;
+            }
         } while (token is not null);
 
         return items;
@@ -52,4 +54,24 @@ public sealed class S3StorageService(IAmazonS3 s3) : IStorageService
         };
         await _s3.PutObjectAsync(req, ct);
     }
+
+
+    public async Task<(Stream Stream, string ContentType, long? ContentLength)> GetObjectAsync(
+        string bucket, string key, CancellationToken ct = default)
+    {
+        var resp = await _s3.GetObjectAsync(new GetObjectRequest
+        {
+            BucketName = bucket,
+            Key = key
+        }, ct);
+
+        // ResponseStream NICHT kopieren, sondern direkt zurückgeben (Server streamt es weiter)
+        var contentType = string.IsNullOrWhiteSpace(resp.Headers.ContentType)
+            ? "application/octet-stream"
+            : resp.Headers.ContentType;
+
+        long? len = resp.Headers.ContentLength >= 0 ? resp.Headers.ContentLength : null;
+        return (resp.ResponseStream, contentType, len);
+    }
+
 }