PRE / POST hooks

storages/backends/base.py

@@ -0,0 +1,9 @@
+from django.core.files.base import File
+from django.core.files.storage import Storage
+
+class BaseFile(File):
+    pass
+
+class BaseStorage(Storage):
+    def pre_save(self, name, content):
+        return name, content

storages/backends/s3boto3.py

@@ -10,14 +10,14 @@
 from django.conf import settings as django_settings
 from django.core.exceptions import ImproperlyConfigured, SuspiciousOperation
 from django.core.files.base import File
-from django.core.files.storage import Storage
 from django.utils.deconstruct import deconstructible
 from django.utils.encoding import (
     filepath_to_uri, force_bytes, force_text, smart_text,
 )
 from django.utils.six.moves.urllib import parse as urlparse
 from django.utils.timezone import is_naive, localtime
 
+from storages.backends.base import BaseStorage, BaseFile
 from storages.utils import (
     check_location, get_available_overwrite_name, lookup_env, safe_join,
     setting,
@@ -37,7 +37,7 @@
 
 
 @deconstructible
-class S3Boto3StorageFile(File):
+class S3Boto3StorageFile(BaseFile):
 
     """
     The default file object used by the S3Boto3Storage backend.
@@ -168,7 +168,7 @@ def close(self):
 
 
 @deconstructible
-class S3Boto3Storage(Storage):
+class S3Boto3Storage(BaseStorage):
     """
     Amazon Simple Storage Service using Boto3
 
@@ -469,6 +469,7 @@ def _open(self, name, mode='rb'):
         return f
 
     def _save(self, name, content):
+        name, content = self.pre_save(name, content)
         cleaned_name = self._clean_name(name)
         name = self._normalize_name(cleaned_name)
         parameters = self.object_parameters.copy()