make storage plugin dependency installation more flexible

inventory/byo/hosts.example

@@ -75,6 +75,10 @@ openshift_master_identity_providers=[{'name': 'htpasswd_auth', 'login': 'true',
 # default project node selector
 #osm_default_node_selector='region=primary'
 
+# default storage plugin dependencies to install, by default the ceph and
+# glusterfs plugin dependencies will be installed, if available.
+#osn_storage_plugin_deps=['ceph','glusterfs']
+
 # default selectors for router and registry services
 # openshift_router_selector='region=infra'
 # openshift_registry_selector='region=infra'

roles/openshift_facts/library/openshift_facts.py

@@ -469,6 +469,21 @@ def set_aggregate_facts(facts):
 
     return facts
 
+def set_node_plugin_facts_if_unset(facts):
+    """ Set Facts for node storage plugin dependencies if not set.
+
+        Args:
+            facts (dict): existing facts
+        Returns:
+            dict: the facts dict updated with the generated storage plugin
+            dependency facts
+    """
+    if 'node' in facts:
+        if 'storage_plugin_deps' not in facts['node']:
+            facts['node']['storage_plugin_deps'] = ['ceph', 'glusterfs']
+
+    return facts
+
 def set_deployment_facts_if_unset(facts):
     """ Set Facts that vary based on deployment_type. This currently
         includes common.service_type, common.config_base, master.registry_url,
@@ -814,6 +829,7 @@ class OpenShiftFacts(object):
         facts = set_identity_providers_if_unset(facts)
         facts = set_sdn_facts_if_unset(facts)
         facts = set_deployment_facts_if_unset(facts)
+        facts = set_node_plugin_facts_if_unset(facts)
         facts = set_aggregate_facts(facts)
         return dict(openshift=facts)
 

roles/openshift_node/tasks/main.yml

@@ -32,6 +32,7 @@
       schedulable: "{{ openshift_schedulable | default(openshift_scheduleable) | default(None) }}"
       docker_log_driver:  "{{ lookup( 'oo_option' , 'docker_log_driver'  )  | default('',True) }}"
       docker_log_options: "{{ lookup( 'oo_option' , 'docker_log_options' )  | default('',True) }}"
+      storage_plugin_deps: "{{ osn_storage_plugin_deps | default(None) }}"
 
 # We have to add tuned-profiles in the same transaction otherwise we run into depsolving
 # problems because the rpms don't pin the version properly.
@@ -39,15 +40,6 @@
   yum: pkg={{ openshift.common.service_type }}-node{{ openshift_version  }},tuned-profiles-{{ openshift.common.service_type }}-node{{ openshift_version  }} state=present
   register: node_install_result
 
-# TODO: allow for storage pre-requisites to be optional
-- name: Install storage plugin pre-requisites
-  yum:
-    pkg: "{{ item }}"
-    state: installed
-  with_items:
-  - glusterfs-fuse
-  - ceph-common
-
 - name: Install sdn-ovs package
   yum: pkg={{ openshift.common.service_type }}-sdn-ovs{{ openshift_version }} state=present
   register: sdn_install_result
@@ -133,15 +125,8 @@
   notify:
     - restart docker
 
-- name: Set sebooleans to allow storage plugin access from containers
-  seboolean:
-    name: "{{ item }}"
-    state: yes
-    persistent: yes
-  when: ansible_selinux and ansible_selinux.status == "enabled"
-  with_items:
-  - virt_use_nfs
-  - virt_use_fusefs
+- name: Additional storage plugin configuration
+  include: storage_plugins/main.yml
 
 - name: Start and enable node
   service: name={{ openshift.common.service_type }}-node enabled=yes state=started

roles/openshift_node/tasks/storage_plugins/ceph.yml

@@ -0,0 +1,5 @@
+---
+- name: Install Ceph storage plugin dependencies
+  yum:
+    pkg: ceph-common
+    state: installed

roles/openshift_node/tasks/storage_plugins/glusterfs.yml

@@ -0,0 +1,12 @@
+---
+- name: Install GlusterFS storage plugin dependencies
+  yum:
+    pkg: glusterfs-fuse
+    state: installed
+
+- name: Set seboolean to allow gluster storage plugin access from containers
+  seboolean:
+    name: virt_use_fusefs
+    state: yes
+    persistent: yes
+  when: ansible_selinux and ansible_selinux.status == "enabled"

roles/openshift_node/tasks/storage_plugins/main.yml

@@ -0,0 +1,17 @@
+---
+- pause:
+
+# The NFS storage plugin is always enabled since it doesn't require any
+# additional package dependencies
+- name: NFS storage plugin configuration
+  include: nfs.yml
+
+- name: GlusterFS storage plugin configuration
+  include: glusterfs.yml
+  when: "'glusterfs' in openshift.node.storage_plugin_deps"
+
+- name: Ceph storage plugin configuration
+  include: ceph.yml
+  when: "'ceph' in openshift.node.storage_plugin_deps"
+
+- pause:

roles/openshift_node/tasks/storage_plugins/nfs.yml

@@ -0,0 +1,7 @@
+---
+- name: Set seboolean to allow nfs storage plugin access from containers
+  seboolean:
+    name: virt_use_nfs
+    state: yes
+    persistent: yes
+  when: ansible_selinux and ansible_selinux.status == "enabled"