Add el7 specific jenkins packages.

inventory/group_vars/jenkins-slave

@@ -169,5 +169,6 @@ slave_packages_fedora:
 slave_packages_centos:
 # "setup" is just a placeholder value
 - setup
-# el7-only
-#    - python-webob1.4   # Required by bodhi2
+# Packages only installed on el7 slave
+el7-only:
+- python-webob1.4   # Required by bodhi2

roles/jenkins/slave/tasks/main.yml

@@ -43,6 +43,15 @@
   - jenkins/slave
   - packages
 
+- name: install el7 specific slave packages
+  yum: name={{ item }} state=installed
+  with_items: "{{ el7_only }}"
+  when: ansible_distribution_major_version|int == 7
+  tags:
+  - jenkins
+  - jenkins/slave
+  - packages
+
 - name: create jenkins user
   action: user name=jenkins state=present createhome=yes system=no groups=mock
   tags: