AIO: Provide facility to exclude apt distributions

When using a mirror which compiles all apt sources into
a single repo with the intent of relying on that repo for
all package updates the /etc/apt/sources.list file must
contain only the base ubuntu repo.

This patch adds the ability to implement an AIO with
this kind of apt sources configuration, while keeping
the current configuration that's used for gating.

Change-Id: Ia9785a43c9027df86f3bc94f825aba3c43a96e4c

tests/roles/bootstrap-host/defaults/main.yml

@@ -196,6 +196,11 @@ bootstrap_host_data_disk_min_size: 50
 #bootstrap_host_ubuntu_repo: http://archive.ubuntu.com/ubuntu/
 #bootstrap_host_ubuntu_security_repo: http://archive.ubuntu.com/ubuntu/
 
+# Set the distribution suffixes that will be included in the apt repository configuration
+bootstrap_host_apt_distribution_suffix_list:
+  - updates
+  - backports
+
 # Set the components that will be included in the apt repository configuration
 bootstrap_host_apt_components:
   - main

tests/roles/bootstrap-host/tasks/install_packages.yml

@@ -37,18 +37,24 @@
     when:
       - bootstrap_host_ubuntu_security_repo is not defined
     changed_when: false
+    failed_when: false
     tags:
       - find-apt-security-repo
 
   - name: Set apt repo facts based on discovered information
     set_fact:
       bootstrap_host_ubuntu_repo: "{{ ubuntu_repo.stdout_lines[0] }}"
-      bootstrap_host_ubuntu_security_repo: "{{ ubuntu_security_repo.stdout_lines[0] }}"
     when:
       - bootstrap_host_ubuntu_repo is not defined
-      - bootstrap_host_ubuntu_security_repo is not defined
       - ubuntu_repo is defined
+
+  - name: Set apt security repo facts based on discovered information
+    set_fact:
+      bootstrap_host_ubuntu_security_repo: "{{ ubuntu_security_repo.stdout_lines[0] }}"
+    when:
+      - bootstrap_host_ubuntu_security_repo is not defined
       - ubuntu_security_repo is defined
+      - ubuntu_security_repo.stdout_lines | length > 0
 
   - name: Configure apt's sources.list (Ubuntu only)
     template:
@@ -58,7 +64,6 @@
     when:
       - ansible_distribution == 'Ubuntu'
       - bootstrap_host_ubuntu_repo is defined
-      - bootstrap_host_ubuntu_security_repo is defined
     register: apt_sources_configure
 
   - name: Update apt-cache

tests/roles/bootstrap-host/templates/apt-sources.list.j2

@@ -1,10 +1,16 @@
 # {{ ansible_managed }}
 
-# Base repositories
+# Base repository
 deb {{ bootstrap_host_ubuntu_repo }} {{ ansible_distribution_release }} {{ bootstrap_host_apt_components | join(" ") }}
-# Updates repositories
-deb {{ bootstrap_host_ubuntu_repo }} {{ ansible_distribution_release }}-updates {{ bootstrap_host_apt_components | join(" ") }}
-# Backports repositories
-deb {{ bootstrap_host_ubuntu_repo }} {{ ansible_distribution_release }}-backports {{ bootstrap_host_apt_components | join(" ") }}
-# Security repositories
+
+{% if bootstrap_host_apt_distribution_suffix_list | length > 0 %}
+# Additional distribution repositories
+{%   for suffix in bootstrap_host_apt_distribution_suffix_list %}
+deb {{ bootstrap_host_ubuntu_repo }} {{ ansible_distribution_release }}-{{ suffix }} {{ bootstrap_host_apt_components | join(" ") }}
+{%   endfor %}
+{% endif %}
+
+{% if bootstrap_host_ubuntu_security_repo is defined %}
+# Security repository
 deb {{ bootstrap_host_ubuntu_security_repo }} {{ ansible_distribution_release }}-security {{ bootstrap_host_apt_components | join(" ") }}
+{% endif %}