Set empty aws credentials to None.

cms/envs/aws.py

@@ -156,9 +156,14 @@ SEGMENT_IO_KEY = AUTH_TOKENS.get('SEGMENT_IO_KEY')
 if SEGMENT_IO_KEY:
     MITX_FEATURES['SEGMENT_IO'] = ENV_TOKENS.get('SEGMENT_IO', False)
 
-
 AWS_ACCESS_KEY_ID = AUTH_TOKENS["AWS_ACCESS_KEY_ID"]
+if AWS_ACCESS_KEY_ID == "":
+    AWS_ACCESS_KEY_ID = None
+
 AWS_SECRET_ACCESS_KEY = AUTH_TOKENS["AWS_SECRET_ACCESS_KEY"]
+if AWS_SECRET_ACCESS_KEY == "":
+    AWS_SECRET_ACCESS_KEY = None
+
 DATABASES = AUTH_TOKENS['DATABASES']
 MODULESTORE = AUTH_TOKENS['MODULESTORE']
 CONTENTSTORE = AUTH_TOKENS['CONTENTSTORE']

lms/envs/aws.py

@@ -243,7 +243,13 @@ CC_PROCESSOR = AUTH_TOKENS.get('CC_PROCESSOR', CC_PROCESSOR)
 SECRET_KEY = AUTH_TOKENS['SECRET_KEY']
 
 AWS_ACCESS_KEY_ID = AUTH_TOKENS["AWS_ACCESS_KEY_ID"]
+if AWS_ACCESS_KEY_ID == "":
+    AWS_ACCESS_KEY_ID = None
+
 AWS_SECRET_ACCESS_KEY = AUTH_TOKENS["AWS_SECRET_ACCESS_KEY"]
+if AWS_SECRET_ACCESS_KEY == "":
+    AWS_SECRET_ACCESS_KEY = None
+
 AWS_STORAGE_BUCKET_NAME = AUTH_TOKENS.get('AWS_STORAGE_BUCKET_NAME', 'edxuploads')
 
 DATABASES = AUTH_TOKENS['DATABASES']