Eaiser package mgr overrides

also better delegation
added to docs of 'use'

changelogs/fragments/pkg_mgr_peek.yml

@@ -0,0 +1,2 @@
+minor_changes:
+  - package action now has a configuration and local fact that allow to override the package manager to use and not just rely on detection.

lib/ansible/config/base.yml

@@ -1779,6 +1779,16 @@ OLD_PLUGIN_CACHE_CLEARING:
   type: boolean
   default: False
   version_added: "2.8"
+PACKAGE_MANAGER_OVERRIDE:
+  name: Override the package manager
+  description:
+    - When set, allows overriding the detected package manager fact when using the package action.
+  env: [{name: ANSIBLE_PACKAGE_MANAGER_OVERRIDE}]
+  ini:
+    - {key: package_manager_override, section: defaults}
+  vars:
+    - name: ansible_package_manager_override
+  version_added: '2.17'
 PAGER:
   name: pager application to use
   default: less

lib/ansible/modules/package.py

@@ -40,6 +40,8 @@
     description:
       - The required package manager module to use (V(dnf), V(apt), and so on). The default V(auto) will use existing facts or try to autodetect it.
       - You should only use this field if the automatic selection is not working for some reason.
+      - Since version 2.17 you can override the automatic detection both via a local facts by setting 'pkg_mgr' or override both by using the
+        PACKAGE_MANAGER_OVERRIDE configuration settable via ANSIBLE_PACKAGE_MANAGER_OVERRIDE enviornment variable or ansible_package_manager_override variable.
     default: auto
 requirements:
     - Whatever is required for the package plugins specific for each system.

lib/ansible/plugins/action/package.py

@@ -16,6 +16,7 @@
 # along with Ansible.  If not, see <http://www.gnu.org/licenses/>.
 from __future__ import annotations
 
+from ansible import constants as C
 from ansible.errors import AnsibleAction, AnsibleActionFail
 from ansible.executor.module_common import get_action_args_with_defaults
 from ansible.module_utils.facts.system.pkg_mgr import PKG_MGRS
@@ -45,14 +46,20 @@ def run(self, tmp=None, task_vars=None):
         if module == 'auto':
             try:
                 if self._task.delegate_to:  # if we delegate, we should use delegated host's facts
-                    module = self._templar.template("{{hostvars['%s']['ansible_facts']['pkg_mgr']}}" % self._task.delegate_to)
+                    module = C.config.get_config_value('PACKAGE_MANAGER_OVERRIDE', variables=combine_vars(self._task.vars, task_vars.get('delegated_vars', {})))
+                    if module is None:
+                        dh = '%s' % self._task.delegate_to
+                        module = self._templar.template(f"{{hostvars['{dh}']['ansible_local']['pkg_mgr']|default(hostvars['{dh}']['ansible_facts']['pkg_mgr']})}}"
                 else:
-                    module = self._templar.template('{{ansible_facts.pkg_mgr}}')
+                    module = C.config.get_config_value('PACKAGE_MANAGER_OVERRIDE', variables=task_vars)
+                    if module is None:
+                        module = self._templar.template('{{ansible_local.pkg_mgr|default(ansible_facts.pkg_mgr)}}')
             except Exception:
                 pass  # could not get it from template!
 
         try:
             if module == 'auto':
+                # TODO: change to action 'gather_facts'
                 facts = self._execute_module(
                     module_name='ansible.legacy.setup',
                     module_args=dict(filter='ansible_pkg_mgr', gather_subset='!all'),