centralize and complete the internal static vars (#82872)

changelogs/fragments/internal_static_vars.yml

@@ -0,0 +1,3 @@
+bugfixes:
+  - Consolidated the list of internal static vars, centralized them as constant and completed from some missing entries.
+  - Slight optimization to hostvars (instantiate template only once per host, vs per call to var).

lib/ansible/cli/inventory.py

@@ -25,26 +25,6 @@
 
 display = Display()
 
-INTERNAL_VARS = frozenset(['ansible_diff_mode',
-                           'ansible_config_file',
-                           'ansible_facts',
-                           'ansible_forks',
-                           'ansible_inventory_sources',
-                           'ansible_limit',
-                           'ansible_playbook_python',
-                           'ansible_run_tags',
-                           'ansible_skip_tags',
-                           'ansible_verbosity',
-                           'ansible_version',
-                           'inventory_dir',
-                           'inventory_file',
-                           'inventory_hostname',
-                           'inventory_hostname_short',
-                           'groups',
-                           'group_names',
-                           'omit',
-                           'playbook_dir', ])
-
 
 class InventoryCLI(CLI):
     ''' used to display or dump the configured inventory as Ansible sees it '''
@@ -247,7 +227,7 @@ def _get_group(self, gname):
     @staticmethod
     def _remove_internal(dump):
 
-        for internal in INTERNAL_VARS:
+        for internal in C.INTERNAL_STATIC_VARS:
             if internal in dump:
                 del dump[internal]
 

lib/ansible/constants.py

@@ -112,6 +112,46 @@ def __getitem__(self, y):
 DOCUMENTABLE_PLUGINS = CONFIGURABLE_PLUGINS + ('module', 'strategy', 'test', 'filter')
 IGNORE_FILES = ("COPYING", "CONTRIBUTING", "LICENSE", "README", "VERSION", "GUIDELINES", "MANIFEST", "Makefile")  # ignore during module search
 INTERNAL_RESULT_KEYS = ('add_host', 'add_group')
+INTERNAL_STATIC_VARS = frozenset(
+    [
+        "ansible_async_path",
+        "ansible_collection_name",
+        "ansible_config_file",
+        "ansible_dependent_role_names",
+        "ansible_diff_mode",
+        "ansible_config_file",
+        "ansible_facts",
+        "ansible_forks",
+        "ansible_inventory_sources",
+        "ansible_limit",
+        "ansible_play_batch",
+        "ansible_play_hosts",
+        "ansible_play_hosts_all",
+        "ansible_play_role_names",
+        "ansible_playbook_python",
+        "ansible_role_name",
+        "ansible_role_names",
+        "ansible_run_tags",
+        "ansible_skip_tags",
+        "ansible_verbosity",
+        "ansible_version",
+        "inventory_dir",
+        "inventory_file",
+        "inventory_hostname",
+        "inventory_hostname_short",
+        "groups",
+        "group_names",
+        "omit",
+        "hostvars",
+        "playbook_dir",
+        "play_hosts",
+        "role_name",
+        "role_names",
+        "role_path",
+        "role_uuid",
+        "role_names",
+    ]
+)
 LOCALHOST = ('127.0.0.1', 'localhost', '::1')
 MODULE_REQUIRE_ARGS = tuple(add_internal_fqcns(('command', 'win_command', 'ansible.windows.win_command', 'shell', 'win_shell',
                                                 'ansible.windows.win_shell', 'raw', 'script')))

lib/ansible/vars/hostvars.py

@@ -21,26 +21,9 @@
 
 from collections.abc import Mapping
 
+from ansible import constants as C
 from ansible.template import Templar, AnsibleUndefined
 
-STATIC_VARS = [
-    'ansible_version',
-    'ansible_play_hosts',
-    'ansible_dependent_role_names',
-    'ansible_play_role_names',
-    'ansible_role_names',
-    'inventory_hostname',
-    'inventory_hostname_short',
-    'inventory_file',
-    'inventory_dir',
-    'groups',
-    'group_names',
-    'omit',
-    'playbook_dir',
-    'play_hosts',
-    'role_names',
-    'ungrouped',
-]
 
 __all__ = ['HostVars', 'HostVarsVars']
 
@@ -134,10 +117,12 @@ class HostVarsVars(Mapping):
     def __init__(self, variables, loader):
         self._vars = variables
         self._loader = loader
+        # NOTE: this only has access to the host's own vars,
+        # so templates that depend on vars in other scopes will not work.
+        self._templar = Templar(variables=self._vars, loader=self._loader)
 
     def __getitem__(self, var):
-        templar = Templar(variables=self._vars, loader=self._loader)
-        return templar.template(self._vars[var], fail_on_undefined=False, static_vars=STATIC_VARS)
+        return self._templar.template(self._vars[var], fail_on_undefined=False, static_vars=C.INTERNAL_STATIC_VARS)
 
     def __contains__(self, var):
         return (var in self._vars)
@@ -150,5 +135,4 @@ def __len__(self):
         return len(self._vars.keys())
 
     def __repr__(self):
-        templar = Templar(variables=self._vars, loader=self._loader)
-        return repr(templar.template(self._vars, fail_on_undefined=False, static_vars=STATIC_VARS))
+        return repr(self._templar.template(self._vars, fail_on_undefined=False, static_vars=C.INTERNAL_STATIC_VARS))