Support backend storage from field

thumbnails/fields.py

@@ -18,9 +18,7 @@ class ImageField(DjangoImageField):
     def __init__(self, *args, **kwargs):
         self.resize_source_to = kwargs.pop('resize_source_to', None)
         self.pregenerated_sizes = kwargs.pop('pregenerated_sizes', [])
-        if kwargs.get('storage'):
-            raise ValueError('Please define storage backend in settings.py instead on the field itself')
-        self.storage_backend = storage.get_backend()
+        self.storage_backend = storage.get_backend() or kwargs.get('storage')
         self.metadata_backend = metadata.get_backend()
         kwargs['storage'] = self.storage_backend
         super(ImageField, self).__init__(*args, **kwargs)

thumbnails/files.py

@@ -89,7 +89,7 @@ def get(self, size, create=True):
 
         if thumbnail is None:
             thumbnail = images.get(self.source_image.name, size,
-                                   self.metadata_backend, self.storage)
+                                   self.storage, self.metadata_backend)
 
             if thumbnail is None:
                 thumbnail = self.create(size)
@@ -103,15 +103,15 @@ def create(self, size):
         Creates and return a thumbnail of a given size.
         """
         thumbnail = images.create(self.source_image.name, size,
-                                  self.metadata_backend, self.storage)
+                                  self.storage, self.metadata_backend)
         return thumbnail
 
     def delete(self, size):
         """
         Deletes a thumbnail of a given size
         """
         images.delete(self.source_image.name, size,
-                      self.metadata_backend, self.storage)
+                      self.storage, self.metadata_backend)
 
         if self._thumbnails is not None and self._thumbnails.get(size):
             del(self._thumbnails[size])

thumbnails/images.py

@@ -66,14 +66,11 @@ def get_thumbnail_name(source_name, size):
     return os.path.join(conf.BASE_DIR, filename)
 
 
-def create(source_name, size, metadata_backend=None, storage_backend=None):
+def create(source_name, size, storage_backend, metadata_backend=None):
     """
     Creates a thumbnail file and its relevant metadata. Returns a
     Thumbnail instance.
     """
-
-    if storage_backend is None:
-        storage_backend = backends.storage.get_backend()
     if metadata_backend is None:
         metadata_backend = backends.metadata.get_backend()
 
@@ -91,12 +88,10 @@ def save(source_name, size, metadata_backend, storage_backend, image_file):
     return Thumbnail(metadata=metadata, storage=storage_backend)
 
 
-def get(source_name, size, metadata_backend=None, storage_backend=None):
+def get(source_name, size, storage_backend, metadata_backend=None):
     """
     Returns a Thumbnail instance, or None if thumbnail does not yet exist.
     """
-    if storage_backend is None:
-        storage_backend = backends.storage.get_backend()
     if metadata_backend is None:
         metadata_backend = backends.metadata.get_backend()
 
@@ -107,12 +102,10 @@ def get(source_name, size, metadata_backend=None, storage_backend=None):
         return Thumbnail(metadata=metadata, storage=storage_backend)
 
 
-def delete(source_name, size, metadata_backend=None, storage_backend=None):
+def delete(source_name, size, storage_backend, metadata_backend=None):
     """
     Deletes a thumbnail file and its relevant metadata.
     """
-    if storage_backend is None:
-        storage_backend = backends.storage.get_backend()
     if metadata_backend is None:
         metadata_backend = backends.metadata.get_backend()
 

thumbnails/management/commands/delete_thumbnails.py

@@ -38,8 +38,7 @@ def handle(self, path_to_model, field_name, size, *args, **kwargs):
         instances = model.objects.exclude(**exclude_args)
 
         metadata_backend = metadata.get_backend()
-        storage_backend = storage.get_backend()
 
         for instance in instances:
             field = getattr(instance, field_name)
-            images.delete(field.name, size, metadata_backend, storage_backend)
+            images.delete(field.name, size, field.thumbnails.storage, metadata_backend)

thumbnails/tests/test_images.py

@@ -42,7 +42,7 @@ def test_create(self):
         self.assertFalse(self.storage_backend.exists(thumbnail_name))
 
         thumbnail = images.create(self.source_name, 'small',
-                                  self.metadata_backend, self.storage_backend)
+                                  self.storage_backend, self.metadata_backend)
         self.assertTrue(self.storage_backend.exists(thumbnail.name))
         self.assertNotEqual(
             self.metadata_backend.get_thumbnail(self.source_name, 'small'),
@@ -55,15 +55,15 @@ def test_get(self):
         """
         self.assertEqual(
             images.get(self.source_name, 'default',
-                       self.metadata_backend, self.storage_backend),
+                       self.storage_backend, self.metadata_backend),
             None
         )
         thumbnail = images.create(self.source_name, 'default',
-                                  self.metadata_backend, self.storage_backend)
+                                  self.storage_backend, self.metadata_backend)
 
         self.assertEqual(
             images.get(self.source_name, 'default',
-                       self.metadata_backend, self.storage_backend),
+                       self.storage_backend, self.metadata_backend),
             thumbnail
         )
 
@@ -83,10 +83,10 @@ def test_delete(self):
         Ensure that ``delete`` works properly.
         """
         thumbnail = images.create(self.source_name, 'small',
-                                  self.metadata_backend, self.storage_backend)
+                                  self.storage_backend, self.metadata_backend)
 
         images.delete(self.source_name, 'small',
-                      self.metadata_backend, self.storage_backend)
+                      self.storage_backend, self.metadata_backend)
         self.assertFalse(self.storage_backend.exists(thumbnail.name))
         self.assertEqual(
             self.metadata_backend.get_thumbnail(self.source_name, 'small'),
@@ -95,7 +95,7 @@ def test_delete(self):
 
         # key with format is not defined in settings anymore
         thumbnail = images.create(self.source_name, 'source_with_format',
-                                  self.metadata_backend, self.storage_backend)
+                                  self.storage_backend, self.metadata_backend)
 
         thumbnail_size_data = {
             'small': {
@@ -107,7 +107,7 @@ def test_delete(self):
         with patch('thumbnails.images.conf.SIZES', thumbnail_size_data):
             # ensure error not happening, and its files and metadata are still removed
             images.delete(self.source_name, 'source_with_format',
-                          self.metadata_backend, self.storage_backend)
+                          self.storage_backend, self.metadata_backend)
             self.assertFalse(self.storage_backend.exists(thumbnail.name))
             self.assertIsNone(self.metadata_backend.get_thumbnail(self.source_name, 'source_with_format'))
 
@@ -128,7 +128,7 @@ def test_delete_with_no_thumbnails_file(self):
         self.assertFalse(os.path.exists(thumbnail_path))
 
         images.delete(self.source_name, size,
-                      self.metadata_backend, self.storage_backend)
+                      self.storage_backend, self.metadata_backend)
 
         # thumbnails and their metadata are also deleted
         self.assertEqual(len(os.listdir(avatar_folder)), 0)