k8s-clusters/ansible/build-k3s-cluster.yml

- name: debug stuff
  hosts: all
  tasks:
    - name: set token fact for k3s-nodes hosts
      run_once: true
      with_items: '{{ groups["k3s-nodes"] }}'
      delegate_to: '{{ item }}'
      set_fact:
        fake_hostname: '{{ hostvars[item]["inventory_hostname"] }} for {{ item }}'

    - name: debug token fact for k3s-nodes hosts
      run_once: true
      with_items: '{{ groups["k3s-nodes"] }}'
      delegate_to: '{{ item }}'
      debug:
        msg: '{{ hostvars[item]["fake_hostname"] }} for {{ inventory_hostname }}'

- name: install k3s on k3s-nodes
  hosts: k3s-nodes
  gather_facts: yes
  roles:
    - role: k3s-node

# TODO: ensure odd number of k3s-control-nodes hosts

- name: intialize k3s cluster on first control plane node
  hosts: k3s-control-nodes[0]
  tasks:
    - name: create config directory
      file:
        recurse: yes
        path: /etc/rancher/k3s/
        state: directory
        mode: '0700'

    - name: copy initial config
      become: true
      copy:
        src: ./templates/k3s-initial-server-config.yaml
        dest: /etc/rancher/k3s/config.yaml

    - name: run initial k3s server
      become: true
      ansible.builtin.command: systemctl enable --now k3s

    - name: fetch token
      become: true
      slurp: 
        src: /var/lib/rancher/k3s/server/node-token
      register: slurped_k3s_node_token

    - name: set token fact for initial node
      set_fact:
        k3s_node_token: '{{ slurped_k3s_node_token.content | b64decode }}'

- name: configure remaining nodes
  hosts: k3s-nodes,!k3s-control-nodes[0]
  gather_facts: no
  tasks:
    - name: debug info
      ansible.builtin.debug:
        msg: '{{ ansible_facts }}'

    # - name: debug token fact for k3s-nodes hosts
    #   run_once: true
    #   debug:
    #     msg: '{{ hostvars[groups["k3s-control-nodes"][0]]["k3s_node_token"] }}'

    - name: set token fact
      set_fact:
        k3s_node_token: '{{ hostvars[groups["k3s-control-nodes"][0]]["k3s_node_token"] }}'

    - name: configure k3s server with token
      lineinfile:
        path: /etc/systemd/system/k3s.service.env
        state: present
        line: K3S_TOKEN={{ k3s_node_token }}
        create: yes

    - name: configure k3s agent with token
      lineinfile:
        path: /etc/systemd/system/k3s-agent.service.env
        state: present
        line: K3S_TOKEN={{ k3s_node_token }}
        create: yes

    - name: create config directory
      file:
        recurse: yes
        path: /etc/rancher/k3s/
        state: directory
        mode: '0700'

    - name: configure k3s server endpoint
      lineinfile:
        path: /etc/rancher/k3s/config.yaml
        state: present
        line: 'server: https://{{ hostvars[groups["k3s-control-nodes"][0]]["ansible_default_ipv4"]["address"] }}:6443'
        create: yes

    # TODO: assert token is valid?
    # - name: debug info2
    #   ansible.builtin.debug:
    #     msg: '{{ k3s_node_token }}'
    # TODO: wait for initial control node to come up?

- name: start remaining control nodes
  hosts: k3s-control-nodes,!k3s-control-nodes[0]
  tasks:
    - name: run k3s
      become: true
      ansible.builtin.command: systemctl enable --now k3s

- name: start remaining agent nodes
  hosts: k3s-agent-nodes
  tasks:
    - name: run k3s
      become: true
      ansible.builtin.command: systemctl enable --now k3s-agent