Programatically adjust container-prepare-parameters for standalone

This change will ensure we're programatically adjusting the
container-prepare-parameters.yaml file when running jobs in
standalone. While this change will ensure our file adjustments
are always YAML complient, it will also ensure we're only
writting the file once and not setting a "tag_from_label" to
null when running upstream jobs which causes a cache miss with
infra; a cache miss can result in ratelimit errors from docker
hub's anon-login restrictions.

Change-Id: I110dc536129b78e3794705ece5bc7bc5d1c44352
Signed-off-by: Kevin Carter <kecarter@redhat.com>

roles/standalone/tasks/main.yml

@@ -188,49 +188,66 @@
         add_repos_update: ",{{ add_repos_update | join(',') }}"
       when: add_repos_update|length > 0
 
+- name: Load the container params file data
+  slurp:
+    src: "{{ working_dir }}/containers-prepare-parameters.yaml"
+  register: containers_prepare_parameters
+
+- name: Parse container params
+  set_fact:
+    containers_prepare_parameters_yaml: "{{ containers_prepare_parameters['content'] | b64decode | from_yaml }}"
+
 # update params for container update
 - name: Add updates to container-prepare-parameters.yaml
   when:
     - standalone_container_prep_updates
     - not job.build_container_images|default(false)|bool
   block:
-    - name: Replace tag_from_label value
-      replace:
-        path: "{{ working_dir }}/containers-prepare-parameters.yaml"
-        regexp: " tag_from_label: (.*)"
-        replace: " tag_from_label: null"
-        backup: true
-
-    - name: Add settings to modify
-      blockinfile:
-        path: "{{ working_dir }}/containers-prepare-parameters.yaml"
-        state: present
-        backup: true
-        insertbefore: "(.*) tag_from_label: null"
-        block: |
-          #
-              push_destination: "{{ local_docker_registry_host }}:8787"
-              modify_role: tripleo-modify-image
-              modify_append_tag: "{{ update_containers_append_tag }}"
-              {% if osp_release is defined -%}
-              # no kolla labels are defined
-              {% else -%}
-              modify_only_with_labels:
-              - kolla_version
-              - tcib_managed
-              {% endif -%}
-              modify_vars:
-                tasks_from: yum_update.yml
-                yum_repos_dir_path: /etc/yum.repos.d
-                update_repo: "{{ standalone_container_prep_update_repo }}{{ add_repos_update|default('') }}"
+    - name: Generate modified containers file
+      set_fact:
+        containers_prepare_parameters_yaml: |-
+          {% set imageParams = [] %}
+          {% for item in containers_prepare_parameters_yaml['parameter_defaults']['ContainerImagePrepare'] %}
+          {%   set _ = item.__setitem__("push_destination", local_docker_registry_host ~ ":8787") %}
+          {%   set _ = item.__setitem__("modify_role", "tripleo-modify-image") %}
+          {%   set _ = item.__setitem__("modify_append_tag", update_containers_append_tag) %}
+          {% if not (osp_release is defined) %}
+          {%   set _ = item.__setitem__("modify_only_with_labels", ["kolla_version", "tcib_managed"]) %}
+          {% endif %}
+          {%   set _ = item.__setitem__(
+                "modify_vars",
+                {
+                  "tasks_from": "yum_update.yml",
+                  "yum_repos_dir_path": "/etc/yum.repos.d",
+                  "update_repo": standalone_container_prep_update_repo ~ add_repos_update | default('')
+                }
+              )
+          %}
+          {%   set _ = item.pop("tag_from_label", "") %}
+          {%   set _ = imageParams.append(item) %}
+          {% endfor %}
+          {% set defaults = {"ContainerImagePrepare": imageParams} %}
+          {{ {"parameter_defaults": defaults} }}
 
 - name: Update rhel_containers value
-  when: ansible_distribution == 'RedHat'
-  replace:
-    path: "{{ working_dir }}/containers-prepare-parameters.yaml"
-    regexp: "rhel_containers: false"
-    replace: "rhel_containers: true"
-    backup: true
+  when:
+    - ansible_distribution == 'RedHat'
+  set_fact:
+    containers_prepare_parameters_yaml: |-
+      {% set imageParams = [] %}
+      {% for item in (containers_prepare_parameters_yaml | from_yaml)['parameter_defaults']['ContainerImagePrepare'] %}
+      {%   if "set" in item %}
+      {%     set _ = item['set'].__setitem__("rhel_containers", true) %}
+      {%   endif %}
+      {%   set _ = imageParams.append(item) %}
+      {% endfor %}
+      {% set defaults = {"ContainerImagePrepare": imageParams} %}
+      {{ {"parameter_defaults": defaults} }}
+
+- name: Write containers-prepare-parameters.yaml
+  copy:
+    content: "{{ containers_prepare_parameters_yaml | to_nice_yaml }}"
+    dest: "{{ working_dir }}/containers-prepare-parameters.yaml"
 
 - name: Modify the insecure registry value when using podman
   when: