Respect yml_multilines for JSON configs

At the moment there is no good way to have new lines ("\n") in JSON
files and not to convert the result to a list.
In the meanwhile this can be totally expected/required thing to do,
for example to define cloud-init vendor data [1]

[1] https://cloudinit.readthedocs.io/en/latest/reference/datasources/openstack.html#vendor-data

Related-Bug: #2073171
Change-Id: I00d74a26357a8458e38d9eb816a3f3eceeae1e0d

plugins/action/config_template.py

@@ -556,7 +556,8 @@ class ActionModule(ActionBase):
         merged_resultant = self._merge_dict(
             base_items=original_resultant,
             new_items=config_overrides,
-            list_extend=list_extend
+            list_extend=list_extend,
+            yml_multilines=yml_multilines
         )
         return json.dumps(
             merged_resultant,

tests/files/test_multiline_strs.json.expected

@@ -0,0 +1,8 @@
+{
+    "cloud-init": "#cloud-config\npackage_upgrade: True\npackages:\n - htop",
+    "list": [
+        "Curious cat investigates",
+        "a ball of yarn in sight"
+    ],
+    "string": "Freshly baked cookies\n, waiting to be enjoyed."
+}

tests/templates/test_multiline_strs.json

@@ -0,0 +1,3 @@
+{
+    "string": "Freshly baked cookies\n, waiting to be enjoyed."
+}

tests/test-json.yml

@@ -43,3 +43,26 @@
   assert:
     that:
       - "(content_no_overrides_file.content | b64decode | from_json) == (content_no_overrides_file_expected.content | b64decode | from_json)"
+
+
+# Values containing newlines should not be chopped into a list
+# when yml_multilines is set to True
+- name: Test multiline strings in json
+  config_template:
+    src: "{{ playbook_dir }}/templates/test_multiline_strs.json"
+    dest: "/tmp/multiline_strs.json"
+    config_overrides: "{{ test_multiline_strs_json_overrides }}"
+    config_type: json
+    yml_multilines: True
+- name: Read multiline_strs.json
+  slurp:
+    src: /tmp/multiline_strs.json
+  register: multiline_strs_file
+- debug:
+    msg: "Multiline JSON Strings - {{ multiline_strs_file.content | b64decode }}"
+- debug:
+    msg: "Multiline JSON Strings Expected - {{ multiline_strs_json_file_expected.content | b64decode }}"
+- name: Compare files
+  assert:
+    that:
+      - "(multiline_strs_json_file_expected.content | b64decode) == (multiline_strs_file.content | b64decode)"

tests/test.yml

@@ -63,6 +63,11 @@
         src: "{{ playbook_dir }}/files/test_multiline_strs.yml.expected"
       register: multiline_strs_file_expected
 
+    - name: Read expected test_multiline_strs.yml
+      slurp:
+        src: "{{ playbook_dir }}/files/test_multiline_strs.json.expected"
+      register: multiline_strs_json_file_expected
+
     - name: Read expected test_list_only.yml
       slurp:
         src: "{{ playbook_dir }}/files/test_list_only.yml.expected"
@@ -166,6 +171,9 @@
       new_multiline_str: |
         This should not
         be a list
+    test_multiline_strs_json_overrides:
+      "list": "Curious cat investigates\n, a ball of yarn in sight"
+      "cloud-init": "#cloud-config\npackage_upgrade: True\npackages:\n - htop"
     test_list_only_overrides:
       - things: stuff
     test_default_section_overrides: