Make build-test-packages more resilient

OVB failures due to
- ansible_user variable was used instead of ansible_user_id, the first
one being unreliable as is may only be user defined (or undefined).
- lack of become on tasks that needed it

Fixes problem identified by molecule testing
- lack of idempotence on few tasks
- failure when ansible_user variale was not defined

Change-Id: I11adec7104a59bfa29b00c702eb9b7eb6a5c6766
Depends-On: Iade08ee92d7f48e07a625678d2a1c6ac1cd1982b
Partial-Bug: https://tree.taiga.io/project/tripleo-ci-board/task/358
Closes-Bug: #1802825

playbooks/ovb-setup.yml

@@ -14,13 +14,12 @@
 - name: Setup the undercloud
   hosts: undercloud
   gather_facts: yes
-  vars:
-    ansible_user: root
   roles:
     - undercloud-setup
   tasks:
     - name: Add eth2 interface from eth2.conf
       command: os-net-config -c {{ working_dir }}/eth2.conf -v
+      become: yes
       when:
         - network_isolation|bool
         - use_testenv_broker|default(false)|bool

roles/build-test-packages/tasks/dlrn-build.yml

@@ -38,6 +38,7 @@
     rdopkg findpkg -s $PROJECT_NAME -l rdoinfo | grep ^name | awk '{print $2}'
   args:
       chdir: '{{ build_repo_dir }}/DLRN'
+  changed_when: false
 
 - debug:
     msg: "WARNING: Unable to build {{ artg_change.project }}. No pkg found."

roles/build-test-packages/tasks/main.yml

@@ -29,6 +29,7 @@
         - mock
         - openssl-devel
         - redhat-rpm-config
+        - rsync
         - rpm-build
         - rpmdevtools
         - sqlite
@@ -41,6 +42,8 @@
 
 - name: Check if virtualenv is in the system
   shell: "{{ python_cmd }} -m virtualenv --version"
+  args:
+    warn: no
   register: virtualenv_exist
   changed_when: false
   failed_when: false
@@ -65,21 +68,23 @@
 - name: Add user to mock group
   become: yes
   user:
-    name: '{{ ansible_user }}'
+    name: '{{ ansible_user_id }}'
     groups: mock
     append: yes
 
-- name: Remove data files from previous runs
-  file:
-    path: '{{ build_repo_dir }}/DLRN'
-    state: absent
-  when: not dlrn_pre_installed|bool
-
 - name: Ensure DLRN dir is present
   file:
     path: '{{ build_repo_dir }}/DLRN/'
     state: directory
 
+- name: Remove data files from previous runs
+  shell:
+    rm -rf '{{ build_repo_dir }}/DLRN/*'
+  args:
+    warn: no
+  register: result
+  changed_when: result.stdout or result.stderr
+
 - name: drop in the templated version of projects.ini
   template:
     src: projects.ini.j2
@@ -116,7 +121,10 @@
   when: dlrn_pre_installed|bool
 
 - name: copy the DLRN scripts in the virtualenv to the scripts dir
-  shell: "/usr/bin/cp -Rv {{ build_repo_dir }}/dlrn-venv/share/dlrn/scripts {{ build_repo_dir }}/DLRN/"
+  synchronize:
+    src: "{{ build_repo_dir }}/dlrn-venv/share/dlrn/scripts"
+    dest: "{{ build_repo_dir }}/DLRN"
+  delegate_to: "{{ inventory_hostname }}"
 
 - name: Fetch local rdoinfo copy
   git: