Support user defined kubeconfig, fix merging context (#266)

* Support user defined kubeconfig, fix merging context

Signed-off-by: Derek Nola <derek.nola@suse.com>

README.md

@@ -94,13 +94,16 @@ It is assumed that the control node has access to the internet. The playbook wil
 
 ## Kubeconfig
 
-After successful bringup, the kubeconfig of the cluster is copied to the control node  and set as default (`~/.kube/config`).
-Assuming you have [kubectl](https://kubernetes.io/docs/tasks/tools/#kubectl) installed, you to confirm access to your **Kubernetes** cluster use the following:
+After successful bringup, the kubeconfig of the cluster is copied to the control node  and merged with `~/.kube/config` under the `k3s-ansible` context.
+Assuming you have [kubectl](https://kubernetes.io/docs/tasks/tools/#kubectl) installed, you can confirm access to your **Kubernetes** cluster with the following:
 
 ```bash
+kubectl config use-context k3s-ansible
 kubectl get nodes
 ```
 
+If you wish for your kubeconfig to be copied elsewhere and not merged, you can set the `kubeconfig` variable in `inventory.yml` to the desired path.
+
 ## Local Testing
 
 A Vagrantfile is provided that provision a 5 nodes cluster using Vagrant (LibVirt or Virtualbox as provider). To use it:

roles/k3s_server/defaults/main.yml

@@ -2,3 +2,4 @@
 k3s_server_location: "/var/lib/rancher/k3s"
 systemd_dir: "/etc/systemd/system"
 api_port: 6443
+kubeconfig: ~/.kube/config.new

roles/k3s_server/tasks/main.yml

@@ -91,13 +91,33 @@
     - name: Copy kubectl config to local machine
       ansible.builtin.fetch:
         src: ~{{ ansible_user }}/.kube/config
-        dest: ~/.kube/config.new
+        dest: "{{ kubeconfig }}"
         flat: true
 
+    - name: Check whether kubectl is installed on control node
+      ansible.builtin.command: 'kubectl'
+      register: kubectl_installed
+      ignore_errors: yes
+      delegate_to: 127.0.0.1
+      become: false
+      changed_when: false
+
+    - name: Setup kubeconfig k3s-ansible context
+      when: kubeconfig == "~/.kube/config.new" && kubectl_installed.rc == 0
+      ansible.builtin.replace:
+        path: "{{ kubeconfig }}"
+        regexp: 'name: default'
+        replace: 'name: k3s-ansible'
+      delegate_to: 127.0.0.1
+      become: false
+
     - name: Merge with any existing kube config
+      when: kubeconfig == "~/.kube/config.new" && kubectl_installed.rc == 0
       ansible.builtin.shell: |
         TFILE=$(mktemp)
-        KUBECONFIG=~/.kube/config:~/.kube/config.new kubectl config view --flatten > ${TFILE}
+        KUBECONFIG=~/.kube/config.new kubectl rename-context default k3s-ansible
+        KUBECONFIG=~/.kube/config.new kubectl config set-context k3s-ansible --user=k3s-ansible --cluster=k3s-ansible
+        KUBECONFIG=~/.kube/config.new:~/.kube/config kubectl config view --flatten > ${TFILE}
         mv ${TFILE} ~/.kube/config
         rm ~/.kube/config.new
       delegate_to: 127.0.0.1