kubespray/roles/kubernetes/secrets/tasks/check-certs.yml

---
- name: "Check_certs | check if the certs have already been generated on first master"
  find:
    paths: "{{ kube_cert_dir }}"
    patterns: "*.pem"
  delegate_to: "{{groups['kube-master'][0]}}"
  register: kubecert_master
  run_once: true

- name: "Check_certs | Set default value for 'sync_certs', 'gen_certs', and 'secret_changed'  to false"
  set_fact:
    sync_certs: false
    gen_certs: false
    secret_changed: false

- name: "Check certs | check if a cert already exists on node"
  stat:
    path: "{{ kube_cert_dir }}/{{ item }}"
  register: kubecert_node
  with_items:
    - ca.pem
    - node-{{ inventory_hostname }}-key.pem

- name: "Check_certs | Set 'gen_certs' to true"
  set_fact:
    gen_certs: true
  when: "not item in kubecert_master.files|map(attribute='path') | list"
  run_once: true
  with_items: >-
       ['{{ kube_cert_dir }}/ca.pem',
       {% for host in groups['k8s-cluster'] %}
       '{{ kube_cert_dir }}/node-{{ host }}-key.pem'
       {% if not loop.last %}{{','}}{% endif %}
       {% endfor %}]

- name: "Check_certs | Set 'gen_node_certs' to true"
  set_fact:
    gen_node_certs: |-
      {
      {% set existing_certs = kubecert_master.files|map(attribute='path')|list|sort %}
      {% for host in groups['k8s-cluster'] -%}
        {% set host_cert = "%s/node-%s-key.pem"|format(kube_cert_dir, host) %}
        {% if host_cert in existing_certs -%}
        "{{ host }}": False,
        {% else -%}
        "{{ host }}": True,
        {% endif -%}
      {% endfor %}
      }
  run_once: true


- name: "Check_certs | Set 'sync_certs' to true"
  set_fact:
    sync_certs: true
  when: >-
      {%- set certs = {'sync': False} -%}
      {% if gen_node_certs[inventory_hostname] or    
        (not kubecert_node.results[0].stat.exists|default(False)) or
          (not kubecert_node.results[1].stat.exists|default(False)) or
            (kubecert_node.results[1].stat.checksum|default('') != kubecert_master.files|selectattr("path", "equalto", kubecert_node.results[1].stat.path)|first|map(attribute="checksum")|default('')) -%}
              {%- set _ = certs.update({'sync': True}) -%}
      {% endif %}
      {{ certs.sync }}