update charts
diff --git a/charts/k8s-gerrit/tests/helpers/utils.py b/charts/k8s-gerrit/tests/helpers/utils.py
new file mode 100644
index 0000000..804217e
--- /dev/null
+++ b/charts/k8s-gerrit/tests/helpers/utils.py
@@ -0,0 +1,41 @@
+# Copyright (C) 2018 The Android Open Source Project
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+# http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+import random
+import string
+
+
+def check_if_ancestor_image_is_inherited(image, ancestor):
+ """Helper function that looks for a given ancestor image in the layers of a
+ provided image. It can be used to check, whether an image uses the expected
+ FROM-statement
+
+ Arguments:
+ image {docker.images.Image} -- Docker image object to be checked
+ ancestor {str} -- Complete name of the expected ancestor image
+
+ Returns:
+ boolean -- True, if ancestor is inherited by image
+ """
+
+ contains_tag = False
+ for layer in image.history():
+ contains_tag = layer["Tags"] is not None and ancestor in layer["Tags"]
+ if contains_tag:
+ break
+ return contains_tag
+
+
+def create_random_string(length=8):
+ return "".join([random.choice(string.ascii_letters) for n in range(length)]).lower()