set container variables when needed

Only run container tasks when required to:
1. prior to undercloud
2. prior to overcloud-prep-containers
3. prior to standalone deployment

Closes-Bug: #1777896
Change-Id: I50054a95500747972454305001d34c4c97b71e7f

roles/container-prep/README.md

@@ -0,0 +1,9 @@
+container-prep
+==============
+
+The containers used by TripleO are now in use in multiple parts of the
+workflow.  This role is a common role for containers that can be used
+to setup either for the undercloud, standalone or overcloud-prep-containers.
+
+Role Variables
+--------------

roles/container-prep/defaults/main.yml

@@ -0,0 +1 @@
+---

roles/container-prep/meta/main.yml

@@ -0,0 +1,2 @@
+dependencies:
+  - extras-common

roles/container-prep/tasks/main.yml

@@ -0,0 +1,27 @@
+# Conditional facts to be set which are common to undercloud and overcloud
+- name: set docker_registry_namespace_used
+  set_fact:
+    docker_registry_namespace_used: "{{ docker_registry_namespace }}"
+
+- name: set container_build_id from get_build_command
+  set_fact:
+    container_build_id: "{{ get_build_command }}"
+  when: get_build_command is defined
+
+- name: set mixed upgrade container_build_id
+  set_fact:
+    container_build_id: "{{ overcloud_docker_image_tag }}"
+    docker_registry_namespace_used: "{{ overcloud_docker_registry_namespace }}"
+  when:
+  - container_build_id is not defined
+  - use_overcloud_mixed_upgrade|default(false)|bool
+
+- name: set container_build_id from docker_image_tag
+  set_fact:
+    container_build_id: "{{ docker_image_tag }}"
+  when: container_build_id is not defined
+
+- name: Set update_containers_append_tag for the play
+  set_fact:
+    update_containers_append_tag: "{{ lookup('pipe','date +-updated-%Y%m%d%H%M%S') }}"
+  when: update_containers is defined and update_containers|bool and update_containers_append_tag is undefined

roles/extras-common/tasks/main.yml

@@ -1,27 +0,0 @@
-# Conditional facts to be set which are common to undercloud and overcloud
-- name: set docker_registry_namespace_used
-  set_fact:
-    docker_registry_namespace_used: "{{ docker_registry_namespace }}"
-
-- name: set container_build_id from get_build_command
-  set_fact:
-    container_build_id: "{{ get_build_command }}"
-  when: get_build_command is defined
-
-- name: set mixed upgrade container_build_id
-  set_fact:
-    container_build_id: "{{ overcloud_docker_image_tag }}"
-    docker_registry_namespace_used: "{{ overcloud_docker_registry_namespace }}"
-  when:
-  - container_build_id is not defined
-  - use_overcloud_mixed_upgrade|default(false)|bool
-
-- name: set container_build_id from docker_image_tag
-  set_fact:
-    container_build_id: "{{ docker_image_tag }}"
-  when: container_build_id is not defined
-
-- name: Set update_containers_append_tag for the play
-  set_fact:
-    update_containers_append_tag: "{{ lookup('pipe','date +-updated-%Y%m%d%H%M%S') }}"
-  when: update_containers is defined and update_containers|bool and update_containers_append_tag is undefined

roles/overcloud-prep-containers/meta/main.yml

@@ -1,2 +1,3 @@
 dependencies:
   - extras-common
+  - container-prep

roles/standalone/meta/main.yml

@@ -1,2 +1,3 @@
 dependencies:
   - extras-common
+  - container-prep

roles/undercloud-deploy/meta/main.yml

@@ -1,2 +1,3 @@
 dependencies:
   - extras-common
+  - container-prep

roles/undercloud-setup/meta/main.yml

@@ -1,2 +1,3 @@
 dependencies:
   - extras-common
+  - container-prep