Move handling of secondary coredns into jinja

Loops inside the template rather than doing a separate task.

roles/kubernetes-apps/ansible/tasks/coredns.yml

@@ -16,29 +16,8 @@
     - { name: dns-autoscaler, file: dns-autoscaler-clusterrolebinding.yml, type: clusterrolebinding }
     - { name: dns-autoscaler, file: dns-autoscaler-sa.yml, type: sa }
   register: coredns_manifests
-  vars:
-    clusterIP: "{{ skydns_server }}"
   when:
     - dns_mode in ['coredns', 'coredns_dual']
     - inventory_hostname == groups['kube_control_plane'][0]
   tags:
     - coredns
-
-- name: Kubernetes Apps | Lay Down Secondary CoreDNS Template
-  template:
-    src: "{{ item.src }}.j2"
-    dest: "{{ kube_config_dir }}/{{ item.file }}"
-    mode: 0644
-  with_items:
-    - { name: coredns, src: coredns-deployment.yml, file: coredns-deployment-secondary.yml, type: deployment }
-    - { name: coredns, src: coredns-svc.yml, file: coredns-svc-secondary.yml, type: svc }
-    - { name: dns-autoscaler, src: dns-autoscaler.yml, file: coredns-autoscaler-secondary.yml, type: deployment }
-  register: coredns_secondary_manifests
-  vars:
-    clusterIP: "{{ skydns_server_secondary }}"
-    coredns_ordinal_suffix: "-secondary"
-  when:
-    - dns_mode == 'coredns_dual'
-    - inventory_hostname == groups['kube_control_plane'][0]
-  tags:
-    - coredns

roles/kubernetes-apps/ansible/templates/coredns-deployment.yml.j2

@@ -1,3 +1,4 @@
+{% for coredns_ordinal_suffix in coredns_ordinal_suffixes %}
 ---
 apiVersion: apps/v1
 kind: Deployment
@@ -121,3 +122,4 @@ spec:
             - key: hosts
               path: hosts
 {% endif %}
+{% endfor %}

roles/kubernetes-apps/ansible/templates/coredns-svc.yml.j2

@@ -1,3 +1,4 @@
+{% for coredns_ordinal_suffix in coredns_ordinal_suffixes %}
 ---
 apiVersion: v1
 kind: Service
@@ -15,7 +16,7 @@ metadata:
 spec:
   selector:
     k8s-app: kube-dns{{ coredns_ordinal_suffix }}
-  clusterIP: {{ clusterIP }}
+  clusterIP: {{ lookup('vars', 'skydns_server' + (coredns_ordinal_suffix | replace('-', '_'))) }}
   ports:
     - name: dns
       port: 53
@@ -28,3 +29,4 @@ spec:
     - name: metrics
       port: 9153
       protocol: TCP
+{% endfor %}

roles/kubernetes-apps/ansible/templates/dns-autoscaler.yml.j2

@@ -1,4 +1,3 @@
----
 # Copyright 2016 The Kubernetes Authors.
 #
 # Licensed under the Apache License, Version 2.0 (the "License");
@@ -13,6 +12,8 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
+{% for coredns_ordinal_suffix in coredns_ordinal_suffixes %}
+---
 apiVersion: apps/v1
 kind: Deployment
 metadata:
@@ -84,3 +85,4 @@ spec:
         - --configmap=dns-autoscaler{{ coredns_ordinal_suffix }}
         - --target=Deployment/coredns{{ coredns_ordinal_suffix }}
       serviceAccountName: dns-autoscaler
+{% endfor %}

roles/kubernetes-apps/ansible/vars/main.yml

@@ -0,0 +1 @@
+coredns_ordinal_suffixes: "{{ [''] + (dns_mode == 'coredns_dual' | ternary(['-secondary'], [])) }}"