okd/playbooks/openstack/openshift-cluster/evaluate_groups.yml

---
# NOTE: to support scaling, the `masters` and `new_masters` (and analogous for
# `nodes` and `etcd`) groups must be exclusive.
#
# Since Ansible cannot remove a node from a group, the dynamic inventory
# can't e.g. tag all master nodes as part of the `masters` group and then
# add the new ones to `new_masters`. Creating new hosts means refreshing
# the inventory and that would mean bringing all the nodes (old and new)
# into the `masters` group. And that causes the scaleup playbook to fail.
#
# And since the playbooks can't pass data to the dynamic inventory, this
# new/old separation cannot happen there.
#
# So the inventory sets e.g. `openstack_master_nodes` and this playbook
# configures the actual source groups such as `masters`, `new_masters`,
# `nodes`, `etcd`, etc.
- name: Evaluate the OpenStack groups
  any_errors_fatal: true
  hosts: localhost
  connection: local
  gather_facts: no
  become: no
  tasks:
  # This will happen when we're deploying a cluster from scratch. Add all
  # nodes to the `masters` group.
  - name: Create a brand new masters group (no scaling)
    add_host:
      name: "{{ item }}"
      groups: masters
    with_items: "{{ groups.openstack_master_nodes | default([]) }}"
    changed_when: no
    when: >
      openshift_openstack_existing is undefined or
      openshift_openstack_existing.openstack_master_nodes is undefined or
      openshift_openstack_existing.openstack_master_nodes | length == 0

  # This will happen when we are scaling an existing cluster. Add the current
  # nodes to the `masters` groups.
  - name: Create pre-existing masters group
    add_host:
      name: "{{ item }}"
      groups: masters
    with_items: "{{ openshift_openstack_existing.openstack_master_nodes }}"
    changed_when: no
    when:
    - openshift_openstack_existing is defined
    - openshift_openstack_existing.openstack_master_nodes is defined
    - openshift_openstack_existing.openstack_master_nodes | length > 0

  # This will happen when we are scaling an existing cluster. Add the
  # newly-created nodes to the `new_masters` group.
  - name: Create new_masters group
    add_host:
      name: "{{ item }}"
      groups: new_masters
    with_items: "{{ groups.openstack_master_nodes | default([]) | difference(groups.masters) }}"
    changed_when: no
    when:
    - openshift_openstack_existing is defined
    - openshift_openstack_existing.openstack_master_nodes is defined
    - openshift_openstack_existing.openstack_master_nodes | length > 0

  - name: Create a brand new etcd group (no scaling)
    add_host:
      name: "{{ item }}"
      groups: etcd
    with_items: "{{ groups.openstack_etcd_nodes | default([]) }}"
    changed_when: no
    when: >
      openshift_openstack_existing is undefined or
      openshift_openstack_existing.openstack_etcd_nodes is undefined or
      openshift_openstack_existing.openstack_etcd_nodes | length == 0

  - name: Create pre-existing etcd group
    add_host:
      name: "{{ item }}"
      groups: etcd
    with_items: "{{ openshift_openstack_existing.openstack_etcd_nodes }}"
    changed_when: no
    when:
    - openshift_openstack_existing is defined
    - openshift_openstack_existing.openstack_etcd_nodes is defined
    - openshift_openstack_existing.openstack_etcd_nodes | length > 0

  - name: Create new_etcd group
    add_host:
      name: "{{ item }}"
      groups: new_etcd
    with_items: "{{ groups.openstack_etcd_nodes | default([]) | difference(groups.etcd) }}"
    changed_when: no
    when:
    - openshift_openstack_existing is defined
    - openshift_openstack_existing.openstack_etcd_nodes is defined
    - openshift_openstack_existing.openstack_etcd_nodes | length > 0

  - name: Create a brand new nodes group (no scaling)
    add_host:
      name: "{{ item }}"
      groups: nodes
    with_items: "{{ groups.openstack_nodes | default([]) }}"
    changed_when: no
    when: >
      openshift_openstack_existing is undefined or
      openshift_openstack_existing.openstack_nodes is undefined or
      openshift_openstack_existing.openstack_nodes | length == 0

  - name: Create pre-existing nodes group
    add_host:
      name: "{{ item }}"
      groups: nodes
    with_items: "{{ openshift_openstack_existing.openstack_nodes }}"
    changed_when: no
    when:
    - openshift_openstack_existing is defined
    - openshift_openstack_existing.openstack_nodes is defined
    - openshift_openstack_existing.openstack_nodes | length > 0

  - name: Create new_nodes group
    add_host:
      name: "{{ item }}"
      groups: new_nodes
    with_items: "{{ groups.openstack_nodes | default([]) | difference(groups.nodes) }}"
    changed_when: no
    when:
    - openshift_openstack_existing is defined
    - openshift_openstack_existing.openstack_nodes is defined
    - openshift_openstack_existing.openstack_nodes | length > 0

  # TODO(shadower): Do we need to add `new_glusterfs` as well? I saw no
  # mention in the code.
  - name: Create glusterfs group
    add_host:
      name: "{{ item }}"
      groups: glusterfs
    with_items: "{{ groups.openstack_cns_nodes | default([]) }}"
    changed_when: no