Adding a config option to allow disabling locale settings upon module exec

Fixes #15138

docsite/rst/intro_configuration.rst

@@ -479,8 +479,22 @@ different locations::
 
 Most users will not need to use this feature.  See :doc:`developing_plugins` for more details
 
+.. _module_set_locale:
+
+module_set_locale
+=================
+
+This boolean value controls whether or not Ansible will prepend locale-specific environment variables (as specified
+via the :doc:`module_lang` configuration option). By default this is enabled, and results in the LANG and LC_MESSAGES
+being set when the module is executed on the given remote system.
+
+.. note::
+
+    The module_set_locale option was added in Ansible 2.1.
+
 .. _module_lang:
 
+
 module_lang
 ===========
 

examples/ansible.cfg

@@ -22,6 +22,7 @@
 #transport      = smart
 #remote_port    = 22
 #module_lang    = C
+#module_set_locale = True
 
 # plays will gather facts by default, which contain information about
 # the remote system.

lib/ansible/constants.py

@@ -140,6 +140,7 @@ DEFAULT_MODULE_NAME       = get_config(p, DEFAULTS, 'module_name',      None,
 DEFAULT_FORKS             = get_config(p, DEFAULTS, 'forks',            'ANSIBLE_FORKS',            5, integer=True)
 DEFAULT_MODULE_ARGS       = get_config(p, DEFAULTS, 'module_args',      'ANSIBLE_MODULE_ARGS',      '')
 DEFAULT_MODULE_LANG       = get_config(p, DEFAULTS, 'module_lang',      'ANSIBLE_MODULE_LANG',      os.getenv('LANG', 'en_US.UTF-8'))
+DEFAULT_MODULE_SET_LOCALE = get_config(p, DEFAULTS, 'module_set_locale','ANSIBLE_MODULE_SET_LOCALE',True, boolean=True)
 DEFAULT_MODULE_COMPRESSION= get_config(p, DEFAULTS, 'module_compression', None, 'ZIP_DEFLATED')
 DEFAULT_TIMEOUT           = get_config(p, DEFAULTS, 'timeout',          'ANSIBLE_TIMEOUT',          10, integer=True)
 DEFAULT_POLL_INTERVAL     = get_config(p, DEFAULTS, 'poll_interval',    'ANSIBLE_POLL_INTERVAL',    15, integer=True)

lib/ansible/plugins/shell/__init__.py

@@ -31,11 +31,15 @@ _USER_HOME_PATH_RE = re.compile(r'^~[_.A-Za-z0-9][-_.A-Za-z0-9]*$')
 class ShellBase(object):
 
     def __init__(self):
-        self.env = dict(
+        self.env = dict()
+        if C.DEFAULT_MODULE_SET_LOCALE:
+            self.env.update(
+                dict(
                     LANG        = C.DEFAULT_MODULE_LANG,
                     LC_ALL      = C.DEFAULT_MODULE_LANG,
                     LC_MESSAGES = C.DEFAULT_MODULE_LANG,
                 )
+            )
 
     def env_prefix(self, **kwargs):
         env = self.env.copy()