Support kubelet environment file (#142)

* Support kubelet environment file

With 1.11 the kubelet packages now support an external kubelet
environment file. Update the placement of this configuration from the
kubelet.d directory to the /etc/{default|sysconfig}/kubelet file.

Signed-off-by: Craig Tracey <craigtracey@gmail.com>

* Support env vars in kubelet environment file

Add the capability to add environment vars to the kubelet's systemd
environment file. This will let folks add arbitrary env vars for things
like $HOME, etc.

Signed-off-by: Craig Tracey <craigtracey@gmail.com>

ansible/roles/kubernetes-common/defaults/main.yml

@@ -7,6 +7,7 @@ kubernetes_common_primary_interface: eth0
 
 # kubelet_extra_args is a dict of arg:value (ie. 'node-ip: 1.1.1.1' for '--node-ip=1.1.1.1')
 kubernetes_common_kubelet_extra_args: {}
+kubernetes_common_kubelet_env_vars: {}
 kubernetes_common_kubelet_config: {}
 
 kubernetes_common_kubeadm_config:

ansible/roles/kubernetes-common/tasks/main.yml

@@ -33,11 +33,18 @@
 - name: drop extra args kubelet config
   template:
     backup: True
+    dest: "/etc/{{ 'default' if ansible_os_family == 'Debian' else 'sysconfig' }}/kubelet"
+    src: etc/default/kubelet
+  notify:
+    - restart kubelet
+  when: kubernetes_common_primary_interface is defined or kubernetes_common_kubelet_extra_args is defined or kubernetes_common_kubelet_env_vars is defined
+
+- name: delete old kubelet extra args unit file
+  file:
     dest: /etc/systemd/system/kubelet.service.d/09-extra-args.conf
-    src: etc/systemd/system/kubelet.service.d/09-extra-args.conf
+    state: absent
   notify:
     - restart kubelet
-  when: kubernetes_common_primary_interface is defined or kubernetes_common_kubelet_extra_args is defined
 
 - name: ensure firewalld is running
   systemd:

ansible/roles/kubernetes-common/templates/etc/default/kubelet

@@ -0,0 +1,5 @@
+KUBELET_EXTRA_ARGS={% if kubernetes_common_primary_interface is defined %} --node-ip={{kubernetes_node_ip}}{% endif %}{% for k, v in kubernetes_common_kubelet_extra_args.items() %} --{{k}}='{{v}}'{%- endfor %}
+
+{% for k, v in kubernetes_common_kubelet_env_vars.items() %}
+{{k}}='{{v}}'
+{% endfor %}