修复回忆录图片重试状态透传与前端展示

api/tests/test_pdf_service_images.py

@@ -5,6 +5,7 @@ from unittest.mock import AsyncMock, patch, MagicMock
 from PIL import Image
 
 from api.services.pdf_service import PDFService
+from api.services import pdf_service as pdf_service_module
 
 
 class PDFServiceImagesTest(unittest.IsolatedAsyncioTestCase):
@@ -108,3 +109,44 @@ class PDFServiceImagesTest(unittest.IsolatedAsyncioTestCase):
         self.assertGreater(len(pdf_bytes), 100)
         self.assertNotIn(b"IMAGE:", pdf_bytes)
         mock_client.get.assert_called_once_with("https://signed.example.com/0.png?sig=123")
+
+    @patch("api.services.pdf_service.httpx.AsyncClient")
+    @patch("api.services.pdf_service.TencentCosStorageService")
+    async def test_generate_pdf_skips_private_cos_url_when_signing_fails(
+        self,
+        storage_cls,
+        async_client_cls,
+    ):
+        mock_client = AsyncMock()
+        async_client_cls.return_value.__aenter__ = AsyncMock(return_value=mock_client)
+        async_client_cls.return_value.__aexit__ = AsyncMock(return_value=False)
+        storage = MagicMock()
+        storage.get_download_url.side_effect = pdf_service_module.CosDownloadUrlError(
+            "cos unavailable", retryable=True, request_id="req-err"
+        )
+        storage_cls.from_env.return_value = storage
+
+        service = PDFService()
+        book = type("BookStub", (), {"title": "我的回忆录"})()
+        chapter = type(
+            "ChapterStub",
+            (),
+            {
+                "title": "童年的夏天",
+                "content": "那条路我一直记得。\n\n{{{{IMAGE:南方小镇的青石板路}}}}\n\n奶奶常坐在那里。",
+                "images": [
+                    {
+                        "index": 0,
+                        "placeholder": "{{{{IMAGE:南方小镇的青石板路}}}}",
+                        "url": "https://life-echo-dev-1319381411.cos.ap-shanghai.myqcloud.com/memoirs/u1/c1/0.png",
+                        "storage_key": "memoirs/u1/c1/0.png",
+                        "status": "completed",
+                    }
+                ],
+            },
+        )()
+
+        pdf_bytes = await service.generate_pdf(book, [chapter])
+
+        self.assertGreater(len(pdf_bytes), 100)
+        mock_client.get.assert_not_called()