command - Add option to disable argument var expansion (#80512)

* command - Add option to disable argument var expansion

* Use test char that isn't an escape sequence

changelogs/fragments/command-expand-args.yml

@@ -0,0 +1,2 @@
+minor_changes:
+- command - Add option ``expand_argument_vars`` to disable argument expansion and use literal values - https://github.com/ansible/ansible/issues/54162

lib/ansible/modules/command.py

@@ -40,6 +40,14 @@ attributes:
     raw:
       support: full
 options:
+  expand_argument_vars:
+    description:
+      - Expands the arguments that are variables, for example C($HOME) will be expanded before being passed to the
+        command to run.
+      - Set to C(false) to disable expansion and treat the value as a literal argument.
+    type: bool
+    default: true
+    version_added: "2.16"
   free_form:
     description:
       - The command module takes a free form string as a command to run.
@@ -235,6 +243,7 @@ def main():
             argv=dict(type='list', elements='str'),
             chdir=dict(type='path'),
             executable=dict(),
+            expand_argument_vars=dict(type='bool', default=True),
             creates=dict(type='path'),
             removes=dict(type='path'),
             # The default for this really comes from the action plugin
@@ -254,6 +263,7 @@ def main():
     stdin = module.params['stdin']
     stdin_add_newline = module.params['stdin_add_newline']
     strip = module.params['strip_empty_ends']
+    expand_argument_vars = module.params['expand_argument_vars']
 
     # we promissed these in 'always' ( _lines get autoaded on action plugin)
     r = {'changed': False, 'stdout': '', 'stderr': '', 'rc': None, 'cmd': None, 'start': None, 'end': None, 'delta': None, 'msg': ''}
@@ -321,7 +331,8 @@ def main():
     if not module.check_mode:
         r['start'] = datetime.datetime.now()
         r['rc'], r['stdout'], r['stderr'] = module.run_command(args, executable=executable, use_unsafe_shell=shell, encoding=None,
-                                                               data=stdin, binary_data=(not stdin_add_newline))
+                                                               data=stdin, binary_data=(not stdin_add_newline),
+                                                               expand_user_and_vars=expand_argument_vars)
         r['end'] = datetime.datetime.now()
     else:
         # this is partial check_mode support, since we end up skipping if we get here

lib/ansible/plugins/action/shell.py

@@ -4,6 +4,7 @@
 from __future__ import (absolute_import, division, print_function)
 __metaclass__ = type
 
+from ansible.errors import AnsibleActionFail
 from ansible.plugins.action import ActionBase
 
 
@@ -15,6 +16,11 @@ class ActionModule(ActionBase):
         # Shell module is implemented via command with a special arg
         self._task.args['_uses_shell'] = True
 
+        # Shell shares the same module code as command. Fail if command
+        # specific options are set.
+        if "expand_argument_vars" in self._task.args:
+            raise AnsibleActionFail(f"Unsupported parameters for ({self._task.action}) module: expand_argument_vars")
+
         command_action = self._shared_loader_obj.action_loader.get('ansible.legacy.command',
                                                                    task=self._task,
                                                                    connection=self._connection,

test/integration/targets/command_shell/tasks/main.yml

@@ -284,6 +284,30 @@
     that:
       - "command_result6.stdout == '9cd0697c6a9ff6689f0afb9136fa62e0b3fee903'"
 
+- name: check default var expansion
+  command: /bin/sh -c 'echo "\$TEST"'
+  environment:
+    TEST: z
+  register: command_result7
+
+- name: assert vars were expanded
+  assert:
+    that:
+      - command_result7.stdout == '\\z'
+
+- name: check disabled var expansion
+  command: /bin/sh -c 'echo "\$TEST"'
+  args:
+    expand_argument_vars: false
+  environment:
+    TEST: z
+  register: command_result8
+
+- name: assert vars were not expanded
+  assert:
+    that:
+      - command_result8.stdout == '$TEST'
+
 ##
 ## shell
 ##
@@ -546,3 +570,16 @@
       - command_strip.stderr == 'hello \n '
       - command_no_strip.stdout== 'hello \n \r\n'
       - command_no_strip.stderr == 'hello \n \r\n'
+
+- name: run shell with expand_argument_vars
+  shell: echo 'hi'
+  args:
+    expand_argument_vars: false
+  register: shell_expand_failure
+  ignore_errors: true
+
+- name: assert shell with expand_arguments_vars failed
+  assert:
+    that:
+      - shell_expand_failure is failed
+      - "shell_expand_failure.msg == 'Unsupported parameters for (shell) module: expand_argument_vars'"