Merge pull request #547 from julianwachholz/fix/content-seekable

Fix: only seek files when possible

Author: vstoykov

imagekit/cachefiles/__init__.py

@@ -102,7 +102,8 @@ def _generate(self):
         actual_name = self.storage.save(self.name, content)
 
         # We're going to reuse the generated file, so we need to reset the pointer.
-        content.seek(0)
+        if not hasattr(content, "seekable") or content.seekable():
+            content.seek(0)
 
         # Store the generated file. If we don't do this, the next time the
         # "file" attribute is accessed, it will result in a call to the storage