inject_playbooks.md

Inject Playbook (inject_playbooks.yaml)

inject_playbooks.yaml is an example playbook (template) for injection. It is a no-op by default, used to override/modify parameters after the default parameters are loaded, without changing builtin playbooks or role code. KubeKey does not bundle this file; create it in your own project (or local playbook directory).

After creating it, reference it via the playbooks injection mechanism:

spec:
  playbooks:
    - order: 1.5                        # insert between the 1st and 2nd original plays
      path: hook/inject_playbooks.yaml # the injection playbook created in your local project

What you can do

• Use set_fact to override runtime variables of the current host (for a single host play).
• Use add_hostvars to write/override variables on multiple hosts in bulk (like set_fact but across hosts).
• Use debug to print variables and verify the injection took effect.

Full example

The file content is commented out by default; uncomment the relevant block to enable it:

- name: Inject | Inject and override playbook variables
  hosts:
    - all
  tasks:
    # Example 1: override a single variable (applies to all hosts of the current play)
    # - name: Inject | Override a single variable via set_fact
    #   set_fact:
    #     .kubernetes.version: "v1.31.0"

    # Example 2: override variables by group / host condition
    # - name: Inject | Override variables for a specific group
    #   set_fact:
    #     .kubernetes.container_manager: "containerd"
    #   when:
    #     - .groups.k8s_cluster | default list | has .inventory_hostname

    # Example 3: inject variables to multiple hosts in bulk (add_hostvars)
    # - name: Inject | Add host variables to multiple hosts
    #   add_hostvars:
    #     hosts: ["all"]
    #     vars:
    #       custom_label: "injected-by-hook"

    # Example 4: debug — confirm variable values before injection
    # - name: Inject | Debug current variables
    #   debug:
    #     msg: "kubernetes version is {{ .kubernetes.version }}"

Notes

• Injected variables are only valid during the current playbook run (runtime variables) and are not written back to your config file. For persistent customization, prefer declaring it in the config spec.
• Only enable the example when you truly need "recompute / conditional override after the default parameters are loaded".
• Create this file in your own project (or local playbook directory) and reference it by a relative path; the KubeKey builtin package no longer ships it.
• For order positioning, sorting rules, empty-path skipping, etc., see Inject Playbooks.