Fixed #17379 -- Removed management commands deactivation of the locale.

django/apps/registry.py

@@ -124,6 +124,11 @@ class Apps:
     def check_apps_ready(self):
         """Raise an exception if all apps haven't been imported yet."""
         if not self.apps_ready:
+            from django.conf import settings
+            # If "not ready" is due to unconfigured settings, accessing
+            # INSTALLED_APPS raises a more helpful ImproperlyConfigured
+            # exception.
+            settings.INSTALLED_APPS
             raise AppRegistryNotReady("Apps aren't loaded yet.")
 
     def check_models_ready(self):

django/core/management/base.py

@@ -73,6 +73,21 @@ def handle_default_options(options):
         sys.path.insert(0, options.pythonpath)
 
 
+def no_translations(handle_func):
+    """Decorator that forces a command to run with translations deactivated."""
+    def wrapped(*args, **kwargs):
+        from django.utils import translation
+        saved_locale = translation.get_language()
+        translation.deactivate_all()
+        try:
+            res = handle_func(*args, **kwargs)
+        finally:
+            if saved_locale is not None:
+                translation.activate(saved_locale)
+        return res
+    return wrapped
+
+
 class OutputWrapper(TextIOBase):
     """
     Wrapper around stdout/stderr
@@ -171,19 +186,6 @@ class BaseCommand:
         is the list of application's configuration provided by the
         app registry.
 
-    ``leave_locale_alone``
-        A boolean indicating whether the locale set in settings should be
-        preserved during the execution of the command instead of translations
-        being deactivated.
-
-        Default value is ``False``.
-
-        Make sure you know what you are doing if you decide to change the value
-        of this option in your custom command if it creates database content
-        that is locale-sensitive and such content shouldn't contain any
-        translations (like it happens e.g. with django.contrib.auth
-        permissions) as activating any locale might cause unintended effects.
-
     ``stealth_options``
         A tuple of any options the command uses which aren't defined by the
         argument parser.
@@ -194,7 +196,6 @@ class BaseCommand:
     # Configuration shortcuts that alter various logic.
     _called_from_command_line = False
     output_transaction = False  # Whether to wrap the output in a "BEGIN; COMMIT;"
-    leave_locale_alone = False
     requires_migrations_checks = False
     requires_system_checks = True
     # Arguments, common to all commands, which aren't defined by the argument
@@ -323,16 +324,6 @@ class BaseCommand:
         if options.get('stderr'):
             self.stderr = OutputWrapper(options['stderr'], self.stderr.style_func)
 
-        saved_locale = None
-        if not self.leave_locale_alone:
-            # Deactivate translations, because django-admin creates database
-            # content like permissions, and those shouldn't contain any
-            # translations.
-            from django.utils import translation
-            saved_locale = translation.get_language()
-            translation.deactivate_all()
-
-        try:
         if self.requires_system_checks and not options.get('skip_checks'):
             self.check()
         if self.requires_migrations_checks:
@@ -347,9 +338,6 @@ class BaseCommand:
                     self.style.SQL_KEYWORD(connection.ops.end_transaction_sql()),
                 )
             self.stdout.write(output)
-        finally:
-            if saved_locale is not None:
-                translation.activate(saved_locale)
         return output
 
     def _run_checks(self, **kwargs):

django/core/management/commands/compilemessages.py

@@ -27,7 +27,6 @@ class Command(BaseCommand):
     help = 'Compiles .po files to .mo files for use with builtin gettext support.'
 
     requires_system_checks = False
-    leave_locale_alone = True
 
     program = 'msgfmt'
     program_options = ['--check-format']

django/core/management/commands/makemessages.py

@@ -207,7 +207,6 @@ class Command(BaseCommand):
     build_file_class = BuildFile
 
     requires_system_checks = False
-    leave_locale_alone = True
 
     msgmerge_options = ['-q', '--previous']
     msguniq_options = ['--to-code=utf-8']

django/core/management/commands/makemigrations.py

@@ -4,7 +4,9 @@ from itertools import takewhile
 
 from django.apps import apps
 from django.conf import settings
-from django.core.management.base import BaseCommand, CommandError
+from django.core.management.base import (
+    BaseCommand, CommandError, no_translations,
+)
 from django.db import DEFAULT_DB_ALIAS, connections, router
 from django.db.migrations import Migration
 from django.db.migrations.autodetector import MigrationAutodetector
@@ -51,6 +53,7 @@ class Command(BaseCommand):
             help='Exit with a non-zero status if model changes are missing migrations.',
         )
 
+    @no_translations
     def handle(self, *app_labels, **options):
         self.verbosity = options['verbosity']
         self.interactive = options['interactive']

django/core/management/commands/migrate.py

@@ -4,7 +4,9 @@ from importlib import import_module
 
 from django.apps import apps
 from django.core.checks import Tags, run_checks
-from django.core.management.base import BaseCommand, CommandError
+from django.core.management.base import (
+    BaseCommand, CommandError, no_translations,
+)
 from django.core.management.sql import (
     emit_post_migrate_signal, emit_pre_migrate_signal,
 )
@@ -58,6 +60,7 @@ class Command(BaseCommand):
         issues.extend(super()._run_checks(**kwargs))
         return issues
 
+    @no_translations
     def handle(self, *args, **options):
 
         self.verbosity = options['verbosity']

django/core/management/commands/runserver.py

@@ -25,7 +25,6 @@ class Command(BaseCommand):
 
     # Validation is called explicitly each time the server is reloaded.
     requires_system_checks = False
-    leave_locale_alone = True
     stealth_options = ('shutdown_message',)
 
     default_addr = '127.0.0.1'

django/core/management/templates.py

@@ -32,9 +32,6 @@ class TemplateCommand(BaseCommand):
     requires_system_checks = False
     # The supported URL schemes
     url_schemes = ['http', 'https', 'ftp']
-    # Can't perform any active locale changes during this command, because
-    # setting might not be available at all.
-    leave_locale_alone = True
     # Rewrite the following suffixes when determining the target filename.
     rewrite_template_suffixes = (
         # Allow shipping invalid .py files without byte-compilation.

docs/howto/custom-management-commands.txt

@@ -126,52 +126,30 @@ such as :option:`--verbosity` and :option:`--traceback`.
 Management commands and locales
 ===============================
 
-By default, the :meth:`BaseCommand.execute` method deactivates translations
+By default, management commands are executed with the current active locale.
-because some commands shipped with Django perform several tasks (for example,
-user-facing content rendering and database population) that require a
-project-neutral string language.
 
-If, for some reason, your custom management command needs to use a fixed locale,
+If, for some reason, your custom management command must run without an active
-you should manually activate and deactivate it in your
+locale (for example, to prevent translated content from being inserted into
-:meth:`~BaseCommand.handle` method using the functions provided by the I18N
+the database), deactivate translations using the ``@no_translations``
-support code::
+decorator on your :meth:`~BaseCommand.handle` method::
 
-    from django.core.management.base import BaseCommand, CommandError
+    from django.core.management.base import BaseCommand, no_translations
-    from django.utils import translation
 
     class Command(BaseCommand):
         ...
 
+        @no_translations
         def handle(self, *args, **options):
-
-            # Activate a fixed locale, e.g. Russian
-            translation.activate('ru')
-
-            # Or you can activate the LANGUAGE_CODE # chosen in the settings:
-            from django.conf import settings
-            translation.activate(settings.LANGUAGE_CODE)
-
-            # Your command logic here
             ...
 
-            translation.deactivate()
+Since translation deactivation requires access to configured settings, the
+decorator can't be used for commands that work without configured settings.
 
-Another need might be that your command simply should use the locale set in
+.. versionchanged:: 2.1
-settings and Django should be kept from deactivating it. You can achieve
-it by using the :data:`BaseCommand.leave_locale_alone` option.
 
-When working on the scenarios described above though, take into account that
+    The ``@no_translations`` decorator is new. In older versions, translations
-system management commands typically have to be very careful about running in
+    are deactivated before running a command unless the command's
-non-uniform locales, so you might need to:
+    ``leave_locale_alone`` attribute (now removed) is set to ``True``.
-
-* Make sure the :setting:`USE_I18N` setting is always ``True`` when running
-  the command (this is a good example of the potential problems stemming
-  from a dynamic runtime environment that Django commands avoid offhand by
-  deactivating translations).
-
-* Review the code of your command and the code it calls for behavioral
-  differences when locales are changed and evaluate its impact on
-  predictable behavior of your command.
 
 Testing
 =======
@@ -247,21 +225,6 @@ All attributes can be set in your derived class and can be used in
     A boolean; if ``True``, the entire Django project will be checked for
     potential problems prior to executing the command. Default value is ``True``.
 
-.. attribute:: BaseCommand.leave_locale_alone
-
-    A boolean indicating whether the locale set in settings should be preserved
-    during the execution of the command instead of translations being
-    deactivated.
-
-    Default value is ``False``.
-
-    Make sure you know what you are doing if you decide to change the value of
-    this option in your custom command if it creates database content that
-    is locale-sensitive and such content shouldn't contain any translations
-    (like it happens e.g. with :mod:`django.contrib.auth` permissions) as
-    activating any locale might cause unintended effects. See the `Management
-    commands and locales`_ section above for further details.
-
 .. attribute:: BaseCommand.style
 
     An instance attribute that helps create colored output when writing to

docs/releases/1.6.txt

@@ -193,7 +193,7 @@ Minor features
   option is now performed independently from handling of the locale that
   should be active during the execution of the command. The latter can now be
   influenced by the new
-  :attr:`~django.core.management.BaseCommand.leave_locale_alone` internal
+  ``BaseCommand.leave_locale_alone`` internal
   option. See :ref:`management-commands-and-locales` for more details.
 
 * The :attr:`~django.views.generic.edit.DeletionMixin.success_url` of

docs/releases/1.8.txt

@@ -1166,7 +1166,7 @@ Miscellaneous
   that Django includes) will no longer convert null values back to an empty
   string. This is consistent with other backends.
 
-* When the :attr:`~django.core.management.BaseCommand.leave_locale_alone`
+* When the ``BaseCommand.leave_locale_alone``
   attribute is ``False``, translations are now deactivated instead of forcing
   the "en-us" locale. In the case your models contained non-English strings and
   you counted on English translations to be activated in management commands,

docs/releases/2.1.txt

@@ -418,6 +418,11 @@ Miscellaneous
 * The database router :meth:`allow_relation` method is called in more cases.
   Improperly written routers may need to be updated accordingly.
 
+* Translations are no longer deactivated before running management commands.
+  If your custom command requires translations to be deactivated (for example,
+  to insert untranslated content into the database), use the new
+  :ref:`@no_translations decorator <management-commands-and-locales>`.
+
 .. _deprecated-features-2.1:
 
 Features deprecated in 2.1

tests/i18n/test_extraction.py

@@ -194,10 +194,6 @@ class BasicExtractorTests(ExtractorTests):
         self.assertMsgId("Get my line number", po_contents)
         self.assertLocationCommentPresent(self.PO_FILE, 'Get my line number', 'templates', 'test.html')
 
-    def test_force_en_us_locale(self):
-        """Value of locale-munging option used by the command is the right one"""
-        self.assertTrue(MakeMessagesCommand.leave_locale_alone)
-
     def test_extraction_error(self):
         msg = (
             'Translation blocks must not include other block tags: blocktrans '

tests/user_commands/management/commands/leave_locale_alone_true.py

@@ -1,10 +0,0 @@
-from django.core.management.base import BaseCommand
-from django.utils import translation
-
-
-class Command(BaseCommand):
-
-    leave_locale_alone = True
-
-    def handle(self, *args, **options):
-        return translation.get_language()

tests/user_commands/management/commands/no_translations.py

@@ -1,10 +1,9 @@
-from django.core.management.base import BaseCommand
+from django.core.management.base import BaseCommand, no_translations
 from django.utils import translation
 
 
 class Command(BaseCommand):
 
-    leave_locale_alone = False
+    @no_translations
-
     def handle(self, *args, **options):
         return translation.get_language()

tests/user_commands/tests.py

@@ -63,17 +63,16 @@ class CommandTests(SimpleTestCase):
             dance.Command.requires_system_checks = True
         self.assertIn("CommandError", stderr.getvalue())
 
-    def test_deactivate_locale_set(self):
+    def test_no_translations_deactivate_translations(self):
-        # Deactivate translation when set to true
+        """
+        When the Command handle method is decorated with @no_translations,
+        translations are deactivated inside the command.
+        """
+        current_locale = translation.get_language()
         with translation.override('pl'):
-            result = management.call_command('leave_locale_alone_false', stdout=StringIO())
+            result = management.call_command('no_translations', stdout=StringIO())
             self.assertIsNone(result)
-
+        self.assertEqual(translation.get_language(), current_locale)
-    def test_configured_locale_preserved(self):
-        # Leaves locale from settings when set to false
-        with translation.override('pl'):
-            result = management.call_command('leave_locale_alone_true', stdout=StringIO())
-            self.assertEqual(result, "pl")
 
     def test_find_command_without_PATH(self):
         """