refactor(roles): add meta/argument_specs.yml to nine more roles

CONTRIBUTING requires every role to ship a `meta/argument_specs.yml`.
Add it for these nine roles whose `tasks/main.yml` is otherwise
already correct. No behaviour change.

Roles touched: `alternatives`, `elastic_agent`,
`elastic_agent_fleet_server`, `icinga_kubernetes_web`,
`icingaweb2_module_reporting`, `kernel_settings`, `lvm`, `mastodon`,
`proxysql`.

The specs cover the user-facing variables (those without the `__`
prefix) as documented in each role's README. Internal combine-pattern
slots (`__role_var`, `__dependent_var`, `__combined_var`) are not
declared, in line with the convention.

Author: markuslf

CHANGELOG.md

@@ -74,6 +74,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 * **role:hostname, role:kdump, role:timezone**: Add `meta/argument_specs.yml` so Ansible validates the role variables (types, choices) at role entry. No behaviour change.
 * **role:libmaxminddb, role:mod_maxminddb**: Add `meta/argument_specs.yml`. No behaviour change.
 * **role:apps, role:grafana_grizzly, role:mailto_root, role:motd**: Add `meta/argument_specs.yml`. No behaviour change.
+* **role:alternatives, role:elastic_agent, role:elastic_agent_fleet_server, role:icinga_kubernetes_web, role:icingaweb2_module_reporting, role:kernel_settings, role:lvm, role:mastodon, role:proxysql**: Add `meta/argument_specs.yml`. No behaviour change.
 * **role:icingaweb2_module_businessprocess**: README now documents the install behaviour (controller-side download, every-run-overwrite, idempotent module enable). Add `meta/argument_specs.yml`.
 * **role:icingaweb2_module_cube**: README now documents the install behaviour. Add `meta/argument_specs.yml`.
 * **role:icingaweb2_module_fileshipper**: README now documents the install behaviour and the `php-xml`/`php-yaml`/`php-zip` runtime dependency. Add `meta/argument_specs.yml`.

roles/alternatives/meta/argument_specs.yml

@@ -0,0 +1,49 @@
+argument_specs:
+  main:
+    options:
+
+      alternatives__alternatives:
+        type: 'list'
+        elements: 'dict'
+        required: true
+        description: >-
+          List of `update-alternatives` entries to manage.
+        options:
+
+          link:
+            type: 'str'
+            required: false
+            description: >-
+              Path to the symlink that should point at the real
+              executable. Mandatory on Red Hat-family. On Debian only
+              required when the alternative `name` is unknown to the
+              system.
+
+          name:
+            type: 'str'
+            required: true
+            description: 'The generic name of the alternative.'
+
+          path:
+            type: 'str'
+            required: false
+            description: 'Path to the real executable.'
+
+          priority:
+            type: 'int'
+            required: false
+            description: >-
+              Priority weight for `auto` mode (default fallback for
+              creation: 50).
+
+          state:
+            type: 'str'
+            required: false
+            default: 'selected'
+            choices:
+              - 'absent'
+              - 'auto'
+              - 'present'
+              - 'selected'
+            description: >-
+              `selected` (default), `present`, `auto`, or `absent`.

roles/elastic_agent/meta/argument_specs.yml

@@ -0,0 +1,44 @@
+argument_specs:
+  main:
+    options:
+
+      elastic_agent__enrollment_token:
+        type: 'str'
+        required: true
+        description: >-
+          Enrollment token from the Kibana Fleet UI / API used to
+          register this agent with Fleet Server.
+
+      elastic_agent__insecure:
+        type: 'bool'
+        required: false
+        default: false
+        description: >-
+          If `true`, skip TLS verification when enrolling against the
+          Fleet Server.
+
+      elastic_agent__service_enabled:
+        type: 'bool'
+        required: false
+        default: true
+        description: 'Whether elastic-agent.service is enabled at boot.'
+
+      elastic_agent__service_state:
+        type: 'str'
+        required: false
+        default: 'started'
+        choices:
+          - 'reloaded'
+          - 'restarted'
+          - 'started'
+          - 'stopped'
+        description: 'State of elastic-agent.service.'
+
+      elastic_agent__tags:
+        type: 'list'
+        elements: 'str'
+        required: false
+        default: []
+        description: >-
+          Optional list of tags attached to this agent (used for
+          policy assignment / filtering in Fleet).

roles/elastic_agent_fleet_server/meta/argument_specs.yml

@@ -0,0 +1,48 @@
+argument_specs:
+  main:
+    options:
+
+      elastic_agent_fleet_server__insecure:
+        type: 'bool'
+        required: false
+        default: false
+        description: >-
+          If `true`, skip TLS verification when enrolling against the
+          Elasticsearch / Kibana endpoint.
+
+      elastic_agent_fleet_server__policy_id:
+        type: 'str'
+        required: false
+        default: 'fleet-server-policy'
+        description: 'The Fleet Server policy ID to attach the agent to.'
+
+      elastic_agent_fleet_server__service_enabled:
+        type: 'bool'
+        required: false
+        default: true
+        description: 'Whether elastic-agent.service is enabled at boot.'
+
+      elastic_agent_fleet_server__service_state:
+        type: 'str'
+        required: false
+        default: 'started'
+        choices:
+          - 'reloaded'
+          - 'restarted'
+          - 'started'
+          - 'stopped'
+        description: 'State of elastic-agent.service.'
+
+      elastic_agent_fleet_server__service_token:
+        type: 'str'
+        required: true
+        description: >-
+          Service token created via the Elasticsearch API or Kibana
+          Fleet UI. Used to enroll this host as a Fleet Server.
+
+      elastic_agent_fleet_server__url:
+        type: 'str'
+        required: false
+        description: >-
+          Externally reachable URL of this Fleet Server. Defaults to
+          `https://{{ ansible_facts["nodename"] }}:8220`.

roles/icinga_kubernetes_web/meta/argument_specs.yml

@@ -0,0 +1,38 @@
+argument_specs:
+  main:
+    options:
+
+      icinga_kubernetes_web__database_host:
+        type: 'str'
+        required: false
+        description: >-
+          Hostname of the SQL database. Defaults to
+          `{{ icinga_kubernetes__database_host }}`.
+
+      icinga_kubernetes_web__database_login:
+        type: 'dict'
+        required: false
+        description: >-
+          Login credentials for the SQL database. Defaults to
+          `{{ icinga_kubernetes__database_login }}`.
+
+      icinga_kubernetes_web__database_name:
+        type: 'str'
+        required: false
+        description: >-
+          Name of the SQL database. Defaults to
+          `{{ icinga_kubernetes__database_name }}`.
+
+      icinga_kubernetes_web__url:
+        type: 'str'
+        required: false
+        description: >-
+          URL from which the module tarball is downloaded. Defaults to
+          `https://github.com/Icinga/icinga-kubernetes-web/archive/{{ icinga_kubernetes_web__version }}.tar.gz`.
+
+      icinga_kubernetes_web__version:
+        type: 'str'
+        required: true
+        description: >-
+          The module version to install. Possible options:
+          https://github.com/Icinga/icinga-kubernetes-web/releases.

roles/icingaweb2_module_reporting/meta/argument_specs.yml

@@ -0,0 +1,48 @@
+argument_specs:
+  main:
+    options:
+
+      icingaweb2_module_reporting__database_host:
+        type: 'str'
+        required: false
+        default: 'localhost'
+        description: 'Host of the SQL database server.'
+
+      icingaweb2_module_reporting__database_login:
+        type: 'dict'
+        required: true
+        description: >-
+          User account used by the Reporting module to access its SQL
+          database (currently MySQL).
+        options:
+
+          password:
+            type: 'str'
+            required: true
+            description: 'Password for the database user.'
+
+          username:
+            type: 'str'
+            required: true
+            description: 'Database username.'
+
+      icingaweb2_module_reporting__database_name:
+        type: 'str'
+        required: false
+        default: 'icinga_reporting'
+        description: 'Name of the SQL database.'
+
+      icingaweb2_module_reporting__service_enabled:
+        type: 'bool'
+        required: false
+        default: true
+        description: >-
+          Whether the icinga-reporting timer / cron is enabled at
+          boot.
+
+      icingaweb2_module_reporting__version:
+        type: 'str'
+        required: true
+        description: >-
+          The module version to install. Possible options:
+          https://github.com/Icinga/icingaweb2-module-reporting/releases.

roles/kernel_settings/meta/argument_specs.yml

@@ -0,0 +1,81 @@
+argument_specs:
+  main:
+    options:
+
+      kernel_settings__sysctl__group_var:
+        type: 'list'
+        elements: 'dict'
+        required: false
+        default: []
+        description: >-
+          Sysctl entries to apply (`name`/`value`). Group-level
+          override.
+
+      kernel_settings__sysctl__host_var:
+        type: 'list'
+        elements: 'dict'
+        required: false
+        default: []
+        description: >-
+          Sysctl entries to apply (`name`/`value`). Host-level
+          override.
+
+      kernel_settings__sysfs__group_var:
+        type: 'list'
+        elements: 'dict'
+        required: false
+        default: []
+        description: 'sysfs entries to apply. Group-level override.'
+
+      kernel_settings__sysfs__host_var:
+        type: 'list'
+        elements: 'dict'
+        required: false
+        default: []
+        description: 'sysfs entries to apply. Host-level override.'
+
+      kernel_settings__systemd_cpu_affinity__group_var:
+        type: 'str'
+        required: false
+        default: ''
+        description: >-
+          Comma-separated CPU list for systemd `CPUAffinity=`.
+          Group-level override.
+
+      kernel_settings__systemd_cpu_affinity__host_var:
+        type: 'str'
+        required: false
+        default: ''
+        description: >-
+          Comma-separated CPU list for systemd `CPUAffinity=`.
+          Host-level override.
+
+      kernel_settings__transparent_hugepages__group_var:
+        type: 'str'
+        required: false
+        default: ''
+        description: >-
+          Value for `transparent_hugepage/enabled`
+          (`always`/`madvise`/`never`). Group-level override.
+
+      kernel_settings__transparent_hugepages__host_var:
+        type: 'str'
+        required: false
+        default: ''
+        description: >-
+          Value for `transparent_hugepage/enabled`. Host-level override.
+
+      kernel_settings__transparent_hugepages_defrag__group_var:
+        type: 'str'
+        required: false
+        default: ''
+        description: >-
+          Value for `transparent_hugepage/defrag` (`always`, `defer`,
+          `defer+madvise`, `madvise`, `never`). Group-level override.
+
+      kernel_settings__transparent_hugepages_defrag__host_var:
+        type: 'str'
+        required: false
+        default: ''
+        description: >-
+          Value for `transparent_hugepage/defrag`. Host-level override.

roles/lvm/meta/argument_specs.yml

@@ -0,0 +1,37 @@
+argument_specs:
+  main:
+    options:
+
+      lvm__lvs__group_var:
+        type: 'list'
+        elements: 'dict'
+        required: false
+        default: []
+        description: >-
+          List of logical volumes to manage. Group-level override. See
+          README for the full subkey schema (`name`, `vg`, `size`,
+          `filesystem`, `mount_path`, ...).
+
+      lvm__lvs__host_var:
+        type: 'list'
+        elements: 'dict'
+        required: false
+        default: []
+        description: 'List of logical volumes to manage. Host-level override.'
+
+      lvm__vgs__group_var:
+        type: 'list'
+        elements: 'dict'
+        required: false
+        default: []
+        description: >-
+          List of volume groups to manage. Group-level override. See
+          README for the full subkey schema (`name`, `pvs`, `growpart`,
+          ...).
+
+      lvm__vgs__host_var:
+        type: 'list'
+        elements: 'dict'
+        required: false
+        default: []
+        description: 'List of volume groups to manage. Host-level override.'