Dont confuse image archive pdf with actual image

src/documents/tests/test_api_ocr_templates.py

@@ -2,6 +2,7 @@
 
 import json
 import subprocess
+from io import BytesIO
 from pathlib import Path
 from unittest.mock import patch
 
@@ -1384,6 +1385,26 @@ class TestOcrTemplatePreviewAPI(DirectoriesMixin, APITestCase):
         self.assertEqual(response.content, b"image contents")
         render.assert_not_called()
 
+    def test_renders_pdf_archive_for_an_image_upload(self):
+        document = DocumentFactory(
+            owner=self.user,
+            mime_type="image/png",
+            archive_filename="archived-image.pdf",
+            page_count=1,
+        )
+        with Image.new("RGB", (100, 100), "white") as image:
+            image.save(document.source_path, format="PNG")
+            image.save(document.archive_path, format="PDF")
+
+        response = self.client.get(self.preview_url(document))
+
+        self.assertEqual(response.status_code, status.HTTP_200_OK)
+        self.assertEqual(response["Content-Type"], "image/png")
+        self.assertNotEqual(response.content, document.source_path.read_bytes())
+        with Image.open(BytesIO(response.content)) as rendered:
+            self.assertEqual(rendered.format, "PNG")
+            rendered.verify()
+
     @patch("documents.views.subprocess.run")
     def test_renders_the_requested_pdf_page(self, render):
         def render_page(command, **kwargs):

src/documents/views.py

@@ -5892,13 +5892,13 @@ class OcrTemplateViewSet(BulkPermissionMixin, PassUserMixin, ModelViewSet[OcrTem
                 f"Page {page_num} out of range (document has {document.page_count} pages)",
             )
 
-        doc_path = document.archive_path or document.source_path
-        if not doc_path or not Path(doc_path).is_file():
+        archive_path = document.archive_path
+        doc_path = archive_path or document.source_path
+        if not doc_path.is_file():
             raise Http404("Document file not found")
 
-        if document.mime_type and document.mime_type.startswith("image/"):
-            content = Path(doc_path).read_bytes()
-            return HttpResponse(content, content_type=document.mime_type)
+        if archive_path is None and document.mime_type.startswith("image/"):
+            return HttpResponse(doc_path.read_bytes(), content_type=document.mime_type)
 
         with tempfile.TemporaryDirectory(dir=settings.SCRATCH_DIR) as tmp_dir:
             output_prefix = Path(tmp_dir) / "page"