Allow overriding the default base image for convert-image

This change will allow basing the undercloud image off overcloud-full
(as convert-image does not yet support whole disk images) while still
using the supported uefi images for the overcloud.

Change-Id: Ia255383e8fa5b15c3b2318e0e8f624c7ce775fe1

roles/convert-image/README.md

@@ -6,6 +6,7 @@ not needing to maintain/host a specific undercloud image.
 
 ## Variables
 
+* `convert_image_base`: -- base image to convert into an undercloud image
 * `convert_image_working_dir`: -- directory to be used for image conversion
 * `convert_image_template`: jinja template for the script which does the
   conversion

roles/convert-image/defaults/main.yml

@@ -19,3 +19,6 @@ convert_image_install_pkgs:
 convert_image_tempest_plugins: []
 convert_image_host_memory: 2048
 guest_partition: /dev/sda
+
+# Image to use as base
+convert_image_base: "{{ overcloud_image }}"

roles/convert-image/tasks/main.yml

@@ -4,9 +4,9 @@
     src: "{{ convert_image_template }}"
     dest: "{{ convert_image_working_dir }}/convert_image.sh"
 
-- name: "check if we have an {{ overcloud_image }}.qcow2 to start from"
+- name: "check if we have an {{ convert_image_base }}.qcow2 to start from"
   stat:
-    path: "{{ convert_image_working_dir }}/{{ overcloud_image }}.qcow2"
+    path: "{{ convert_image_working_dir }}/{{ convert_image_base }}.qcow2"
   register: overcloud_full_qcow2
 
 # This tasks is not be used in CI or on any public systems
@@ -14,15 +14,15 @@
 - name: set root password for image
   command: >
     virt-customize --smp 2 -m {{ convert_image_host_memory }}
-    -a {{ convert_image_working_dir }}/{{ overcloud_image }}.qcow2
+    -a {{ convert_image_working_dir }}/{{ convert_image_base }}.qcow2
     --root-password password:{{ overcloud_full_root_pwd }}
   when:
     - overcloud_full_root_pwd is defined
     - overcloud_full_qcow2.stat.exists
 
-- name: "copy {{ overcloud_image }}.qcow2 to undercloud.qcow2"
+- name: "copy {{ convert_image_base }}.qcow2 to undercloud.qcow2"
   command: >
-    cp {{ convert_image_working_dir }}/{{ overcloud_image }}.qcow2
+    cp {{ convert_image_working_dir }}/{{ convert_image_base }}.qcow2
        {{ convert_image_working_dir }}/undercloud.qcow2
   changed_when: true
   when: overcloud_full_qcow2.stat.exists and overcloud_as_undercloud|bool

roles/libvirt/setup/undercloud/tasks/convert_image.yml

@@ -2,3 +2,5 @@
 - name: indirect role include (workaround to https://github.com/ansible/ansible/issues/19472)
   include_role:
     name: convert-image
+  vars:
+    convert_image_base: "{{ undercloud_base_image | default(overcloud_image) }}"