Do not 500 when upstream provider is unavailable

api/catalog/api/views/media_views.py

@@ -9,9 +9,12 @@
 from django.http.response import HttpResponse
 from rest_framework import status
 from rest_framework.decorators import action
+from rest_framework.exceptions import APIException
 from rest_framework.response import Response
 from rest_framework.viewsets import ReadOnlyModelViewSet
 
+from sentry_sdk import capture_exception
+
 from catalog.api.controllers import search_controller
 from catalog.api.models import ContentProvider
 from catalog.api.serializers.provider_serializers import ProviderSerializer
@@ -20,6 +23,11 @@
 from catalog.custom_auto_schema import CustomAutoSchema
 
 
+class UpstreamThumbnailException(APIException):
+    status_code = status.HTTP_424_FAILED_DEPENDENCY
+    default_detail = "Could not render thumbnail due to upstream provider error."
+
+
 class MediaViewSet(ReadOnlyModelViewSet):
     swagger_schema = CustomAutoSchema
 
@@ -189,9 +197,11 @@ def _thumbnail_proxy_comm(
 
             return upstream_response, res_status, content_type
         except (HTTPError, RemoteDisconnected, TimeoutError) as exc:
-            raise get_api_exception(f"Failed to render thumbnail: {exc}")
+            capture_exception(exc)
+            raise UpstreamThumbnailException(f"Failed to render thumbnail: {exc}")
         except Exception as exc:
-            raise get_api_exception(
+            capture_exception(exc)
+            raise UpstreamThumbnailException(
                 f"Failed to render thumbnail due to unidentified exception: {exc}"
             )
 

api/test/factory/models/image.py

@@ -0,0 +1,8 @@
+from test.factory.models.media import MediaFactory
+
+from catalog.api.models.image import Image
+
+
+class ImageFactory(MediaFactory):
+    class Meta:
+        model = Image

api/test/image_integration_test.py

@@ -20,6 +20,7 @@
     stats,
     thumb,
     thumb_compression,
+    thumb_error,
     thumb_full_size,
     thumb_webp,
     uuid_validation,
@@ -90,6 +91,10 @@ def test_image_thumb_full_size(image_fixture):
     thumb_full_size(image_fixture)
 
 
+def test_image_thumb_failure(image_fixture):
+    thumb_error(image_fixture)
+
+
 def test_audio_report(image_fixture):
     report("images", image_fixture)
 

api/test/unit/views/media_views_test.py

@@ -0,0 +1,40 @@
+from test.factory.models.image import ImageFactory
+from unittest import mock
+from urllib.error import HTTPError
+
+from rest_framework.test import APIClient
+
+import pytest
+
+from catalog.api.models.image import Image
+
+
+@pytest.fixture
+def api_client() -> APIClient:
+    return APIClient()
+
+
+@pytest.fixture
+def image() -> Image:
+    return ImageFactory.create()
+
+
+@pytest.mark.django_db
+def test_thumb_error(api_client, image):
+    error = None
+
+    def urlopen_503_response(url, **kwargs):
+        nonlocal error
+        error = HTTPError(url, 503, "Bad error upstream whoops", {}, None)
+        raise error
+
+    with mock.patch(
+        "catalog.api.views.media_views.urlopen"
+    ) as urlopen_mock, mock.patch(
+        "catalog.api.views.media_views.capture_exception", autospec=True
+    ) as mock_capture_exception:
+        urlopen_mock.side_effect = urlopen_503_response
+        response = api_client.get(f"/v1/images/{image.identifier}/thumb/")
+
+    assert response.status_code == 424
+    mock_capture_exception.assert_called_once_with(error)