Don't retry on FileNotFound in celery, dramatiq

Author: amureki

pictures/tasks.py

@@ -33,15 +33,11 @@ def _process_picture(
     old = old or []
     storage = utils.reconstruct(*storage)
     if new:
-        try:
-            with storage.open(file_name) as fs:
-                with Image.open(fs) as img:
-                    for picture in new:
-                        picture = utils.reconstruct(*picture)
-                        picture.save(img)
-        except FileNotFoundError:
-            # The file no longer exists (for example, because it was deleted or replaced).
-            return
+        with storage.open(file_name) as fs:
+            with Image.open(fs) as img:
+                for picture in new:
+                    picture = utils.reconstruct(*picture)
+                    picture.save(img)
 
     for picture in old:
         picture = utils.reconstruct(*picture)
@@ -57,7 +53,9 @@ def _process_picture(
     pass
 else:
 
-    @dramatiq.actor(queue_name=conf.get_settings().QUEUE_NAME)
+    @dramatiq.actor(
+        queue_name=conf.get_settings().QUEUE_NAME, throws=(FileNotFoundError,)
+    )
     def process_picture_with_dramatiq(
         storage: tuple[str, list, dict],
         file_name: str,
@@ -91,6 +89,7 @@ def process_picture(  # noqa: F811
     @shared_task(
         ignore_results=True,
         retry_backoff=True,
+        dont_autoretry_for=(FileNotFoundError,),
     )
     def process_picture_with_celery(
         storage: tuple[str, list, dict],

tests/test_tasks.py

@@ -22,20 +22,5 @@ def test_process_picture__file_cannot_be_reopened(image_upload_file):
     )
 
 
-@pytest.mark.django_db
-def test_process_picture__file_missing(image_upload_file):
-    obj = SimpleModel.objects.create(picture=image_upload_file)
-    setattr(
-        obj.picture.file,
-        "open",
-        Mock(side_effect=FileNotFoundError("The file does not exist anymore.")),
-    )
-    tasks._process_picture(
-        obj.picture.storage.deconstruct(),
-        obj.picture.name,
-        new=[i.deconstruct() for i in obj.picture.get_picture_files_list()],
-    )
-
-
 def test_noop():
     tasks.noop()  # does nothing