Use libvirt-python from the distribution on Red Hat systems

The one in PyPI can easily get out of sync, causing breakages.
Since Red Hat systems move pretty quickly, just use the system
package (Bifrost creates the venv with system site packages).

Change-Id: I08da25aa73cdf3dc43886bc746431f6082e804a1

playbooks/roles/bifrost-create-vm-nodes/defaults/required_defaults_CentOS.yml

@@ -19,7 +19,6 @@ required_packages:
  - libvirt-daemon-driver-secret
  - libvirt-daemon-driver-storage
  - libvirt-daemon-kvm
- - pkgconfig
+ - python3-libvirt
- - libvirt-devel
  - edk2-ovmf
 test_vm_emulator: "/usr/libexec/qemu-kvm"

playbooks/roles/bifrost-create-vm-nodes/defaults/required_defaults_Fedora.yml

@@ -9,7 +9,6 @@ required_packages:
  - libvirt
  - libvirt-client
  - libvirt-daemon
- - pkgconfig
+ - python3-libvirt
- - libvirt-devel
  - python3-libselinux
  - edk2-ovmf

playbooks/roles/bifrost-create-vm-nodes/defaults/required_defaults_RedHat.yml

@@ -12,8 +12,7 @@ required_packages:
  - libvirt
  - libvirt-client
  - libvirt-daemon
- - pkgconfig
+ - python3-libvirt
- - libvirt-devel
  - libxslt-devel
  - libxml2-devel
  - edk2-ovmf

playbooks/roles/bifrost-create-vm-nodes/tasks/prepare_libvirt.yml

@@ -22,16 +22,22 @@
     - default_boot_mode != 'uefi'
     - test_vm_secure_boot | bool
 
-- name: install libvirt-python, gunicorn and lxml
+- name: install gunicorn and lxml
   include_role:
     name: bifrost-pip-install
   vars:
     package: "{{ item }}"
   loop:
-    - libvirt-python
     - gunicorn
     - lxml
 
+- name: install libvirt-python if needed
+  include_role:
+    name: bifrost-pip-install
+  vars:
+    package: libvirt-python
+  when: ansible_os_family != 'RedHat'
+
 - name: configure libvirt log filters for qemu
   blockinfile:
     path: /etc/libvirt/libvirtd.conf
@@ -161,6 +167,15 @@
     path: "{{ test_vm_logdir | dirname }}"
     mode: "0755"
 
+# NOTE(dtantsur): pypi version can easily get out of sync, we need to use
+# the version from the distribution.
+- name: edit libvirt-python out of upper constraints
+  lineinfile:
+    path: "{{ upper_constraints_file }}"
+    regexp: "^libvirt\\-python"
+    state: absent
+  when: ansible_os_family == 'RedHat'
+
 - name: install virtualbmc
   include_role:
     name: bifrost-pip-install