fixtest: files present don't interfere with aws credentials

automated_test.py

@@ -52,7 +52,7 @@ def test_aws_credentials(aws_credentials):
     'AWS_SESSION_TOKEN': 'testing',
     'AWS_DEFAULT_REGION': 'us-east-1',
   }
-  assert secrets.aws_credentials() == expected
+  assert secrets.aws_credentials(skip_files=True) == expected
 
 @pytest.mark.parametrize("green", (False, True))
 @pytest.mark.parametrize("num_threads", (0, 5, 20))

cloudfiles/cloudfiles.py

@@ -456,6 +456,8 @@ def download(path):
     num_threads = self.num_threads
     if self.protocol == "file":
       num_threads = 1
+    elif self.protocol == "mem":
+      num_threads = 0
 
     results = schedule_jobs(
       fns=( partial(download, path) for path in paths ), 

cloudfiles/secrets.py

@@ -96,7 +96,7 @@ def google_credentials(bucket = ''):
 
 AWS_CREDENTIALS_CACHE:CredentialCacheType = defaultdict(dict)
 aws_credentials_path = secretpath('aws-secret.json')
-def aws_credentials(bucket = '', service = 'aws'):
+def aws_credentials(bucket = '', service = 'aws', skip_files=False):
   global AWS_CREDENTIALS_CACHE
 
   if service == 's3':
@@ -115,12 +115,13 @@ def aws_credentials(bucket = '', service = 'aws'):
     paths = [ secretpath('{}-{}-secret.json'.format(bucket, service)) ] + paths
 
   aws_credentials = {}
-  aws_credentials_path = secretpath(default_file_path)
-  for aws_credentials_path in paths:
-    if os.path.exists(aws_credentials_path):
-      with open(aws_credentials_path, 'r') as f:
-        aws_credentials = json.loads(f.read())
-      break
+  if not skip_files:
+    aws_credentials_path = secretpath(default_file_path)
+    for aws_credentials_path in paths:
+      if os.path.exists(aws_credentials_path):
+        with open(aws_credentials_path, 'r') as f:
+          aws_credentials = json.loads(f.read())
+        break
 
   if not aws_credentials:
     # did not find any secret json file, will try to find it in environment variables