Install openstackclient into virtualenv

There may be issues caused by updated OpenStack python libraries being
picked up by other services when we install python-openstackclient
globally. So instead install it into its own virtualenv and create a
symlink to the resulting binary.

Change-Id: I43d9baf13dda20d39d3c52faf1f2322eee4884a3
Partial-Bug: 1661708

recipes/client.rb

@@ -4,6 +4,7 @@
 # Recipe:: client
 #
 # Copyright 2014, IBM Corp.
+# Copyright 2017, cloudbau GmbH
 #
 # Licensed under the Apache License, Version 2.0 (the "License");
 # you may not use this file except in compliance with the License.
@@ -20,6 +21,15 @@
 
 python_runtime '2'
 
+python_virtualenv '/opt/osc' do
+  system_site_packages true
+end
+
 python_package 'python-openstackclient' do
   version node['openstack']['common']['client_version']
+  virtualenv '/opt/osc'
+end
+
+link '/usr/local/bin/openstack' do
+  to '/opt/osc/bin/openstack'
 end

spec/client_spec.rb

@@ -13,9 +13,19 @@ describe 'openstack-common::client' do
       expect(chef_run).to install_python_runtime('2')
     end
 
+    it do
+      expect(chef_run).to create_python_virtualenv('/opt/osc')
+        .with(system_site_packages: true)
+    end
+
     it do
       expect(chef_run).to install_python_package('python-openstackclient')
         .with(version: '3.6.0')
     end
+
+    it do
+      expect(chef_run).to create_link('/usr/local/bin/openstack')
+        .with(to: '/opt/osc/bin/openstack')
+    end
   end
 end