molecule: add prepare playbook and bootstrap packages; guard apt repo for non-Debian

molecule/default/molecule.yml

@@ -18,4 +18,5 @@ platforms:
 provisioner:
   name: ansible
   playbooks:
+    prepare: ${MOLECULE_PREPARE_PLAYBOOK:-prepare.yml}
     converge: ${MOLECULE_PLAYBOOK:-converge.yml}

molecule/default/prepare.yml

@@ -0,0 +1,34 @@
+---
+- name: Prepare
+  hosts: all
+  gather_facts: true
+  tasks:
+    - name: Install python3-apt for Debian/Ubuntu
+      apt:
+        name: python3-apt
+        state: present
+        update_cache: yes
+      when: ansible_facts.os_family == 'Debian'
+
+    - name: Install common packages for RedHat family (best-effort)
+      block:
+        - name: Try to install python3-dnf
+          package:
+            name: python3-dnf
+            state: present
+
+        - name: Try to install python3-libselinux
+          package:
+            name: python3-libselinux
+            state: present
+      when: ansible_facts.os_family == 'RedHat'
+      ignore_errors: true
+
+    - name: Install packages for Suse family (best-effort)
+      block:
+        - name: Try to install python3-zypp
+          package:
+            name: python3-zypp
+            state: present
+      when: ansible_facts.os_family == 'Suse'
+      ignore_errors: true

tasks/main.yml

@@ -104,7 +104,7 @@
     repo: >-
       deb [arch={{ ansible_facts.architecture }}]
       {{ docker_repo_url }}/{{ ansible_facts['distribution'] | lower }}
-      {{ ansible_facts['lsb']['codename'] }} {{ docker_apt_release_channel }}
+      {{ ansible_facts['lsb']['codename'] | default(ansible_facts.get('distribution_release', '')) }}
     filename: "{{ docker_apt_filename }}"
     state: present
-  when: docker_add_repo | bool
+  when: docker_add_repo | bool and ansible_facts.os_family == 'Debian'