Set container build hash based on dlrn md5 checksum

Change-Id: Ia4895074b3b87d4bf117352a15aafc92655f80f1
Signed-off-by: Chandan Kumar (raukadah) <chkumar@redhat.com>

roles/container-prep/tasks/main.yml

@@ -15,7 +15,9 @@
 # get_build_command is passing the current hash
 # plus the latest dlrn hash and I'm not sure why
 # http://opendev.org/openstack/tripleo-ci/tree/roles/run-test/templates/oooq_common_functions.sh.j2#n155
-- when: get_build_command is defined
+- when:
+    - get_build_command is defined
+    - ansible_distribution_major_version is version(8, '<') or ansible_distribution == "RedHat"
   block:
     - name: execute build_command
       shell: |
@@ -31,6 +33,33 @@
       tags:
         - undercloud-install
 
+- when:
+    - get_build_command is defined
+    - ansible_distribution_major_version is version(8, '>=')
+    - ansible_distribution == "CentOS"
+  block:
+    - name: Get md5 checksum for centos-8
+      shell: |
+        set -euo pipefail
+        dlrn_base={{ dlrn_baseurl }}
+        if [ -e /etc/ci/mirror_info.sh ]; then
+          source /etc/ci/mirror_info.sh
+          NODEPOOL_RDO_PROXY=${NODEPOOL_RDO_PROXY:-https://trunk.rdoproject.org}
+          dlrn_base=${dlrn_base/https:\/\/trunk.rdoproject.org/$NODEPOOL_RDO_PROXY}
+        fi
+        curl -s --fail --show-error ${dlrn_base}/{{ dlrn_hash_tag }}/delorean.repo.md5
+      register: build_command_output
+      retries: 5
+      tags:
+        - undercloud-install
+
+    - name: set container_build_id from get_build_command - md5
+      set_fact:
+        container_build_id: "{{ build_command_output.stdout }}"
+        cacheable: true
+      tags:
+        - undercloud-install
+
 # docker_image_tag is set to the dlrn hash but uses the tag
 # as a backup default
 # "{{ dlrn_hash|default(dlrn_hash_tag) }}"