helm: 'changed' flag takes 'values' in consideration

Return `changed` `False` is the `values_files` match the `values` of
the existing deployment.

Closes: ansible-collections#274

changelogs/fragments/332_helm_changed_flag_takes_values_in_consideration.yaml

@@ -0,0 +1,3 @@
+---
+bugfixes:
+- helm - ``release_values`` makes ansible always show changed state (https://github.com/ansible-collections/community.kubernetes/issues/274)

molecule/default/roles/helm/tasks/tests_chart.yml

@@ -295,6 +295,22 @@
       - install.status.chart == "{{ chart_test }}-{{ chart_test_version }}"
       - "install.status['values'].revisionHistoryLimit == 0"
 
+- name: "Install {{ chart_test }} from {{ source }} with values_files (again)"
+  helm:
+    binary_path: "{{ helm_binary }}"
+    name: test
+    chart_ref: "{{ chart_source }}"
+    chart_version: "{{ chart_source_version | default(omit) }}"
+    namespace: "{{ helm_namespace }}"
+    values_files:
+      - "{{ role_path }}/files/values.yaml"
+  register: install
+
+- name: "Assert the result is consistent"
+  assert:
+    that:
+      - not (install is changed)
+
 - name: Remove helm namespace
   k8s:
     api_version: v1

plugins/modules/helm.py

@@ -387,6 +387,18 @@ def delete(command, release_name, purge, disable_hook):
     return delete_command
 
 
+def load_values_files(values_files):
+    values = {}
+    for values_file in values_files or []:
+        with open(values_file, 'r') as fd:
+            content = yaml.safe_load(fd)
+            if not isinstance(content, dict):
+                continue
+            for k, v in content.items():
+                values[k] = v
+    return values
+
+
 def main():
     global module
     module = AnsibleModule(
@@ -502,7 +514,12 @@ def main():
             # when deployed without an 'appVersion' chart value the 'helm list' command will return the entry `app_version: ""`
             appversion_is_same = (chart_app_version == released_app_version) or (chart_app_version is None and released_app_version == "")
 
-            if force or release_values != release_status['values'] \
+            if values_files:
+                values_match = release_status['values'] == load_values_files(values_files)
+            else:
+                values_match = release_status['values'] == release_values
+
+            if force or not values_match \
                     or (chart_info['name'] + '-' + chart_info['version']) != release_status["chart"] \
                     or not appversion_is_same:
                 helm_cmd = deploy(helm_cmd, release_name, release_values, chart_ref, wait, wait_timeout,