import os import threading import time import warnings from django.core.signals import setting_changed from django.db import connections, router from django.db.utils import ConnectionRouter from django.dispatch import Signal, receiver from django.utils import timezone from django.utils.functional import empty template_rendered = Signal(providing_args=["template", "context"]) # Most setting_changed receivers are supposed to be added below, # except for cases where the receiver is related to a contrib app. # Settings that may not work well when using 'override_settings' (#19031) COMPLEX_OVERRIDE_SETTINGS = {'DATABASES'} @receiver(setting_changed) def clear_cache_handlers(**kwargs): if kwargs['setting'] == 'CACHES': from django.core.cache import caches caches._caches = threading.local() @receiver(setting_changed) def update_installed_apps(**kwargs): if kwargs['setting'] == 'INSTALLED_APPS': # Rebuild any AppDirectoriesFinder instance. from django.contrib.staticfiles.finders import get_finder get_finder.cache_clear() # Rebuild management commands cache from django.core.management import get_commands get_commands.cache_clear() # Rebuild get_app_template_dirs cache. from django.template.utils import get_app_template_dirs get_app_template_dirs.cache_clear() # Rebuild translations cache. from django.utils.translation import trans_real trans_real._translations = {} @receiver(setting_changed) def update_connections_time_zone(**kwargs): if kwargs['setting'] == 'TIME_ZONE': # Reset process time zone if hasattr(time, 'tzset'): if kwargs['value']: os.environ['TZ'] = kwargs['value'] else: os.environ.pop('TZ', None) time.tzset() # Reset local time zone cache timezone.get_default_timezone.cache_clear() # Reset the database connections' time zone if kwargs['setting'] in {'TIME_ZONE', 'USE_TZ'}: for conn in connections.all(): try: del conn.timezone except AttributeError: pass try: del conn.timezone_name except AttributeError: pass tz_sql = conn.ops.set_time_zone_sql() if tz_sql: with conn.cursor() as cursor: cursor.execute(tz_sql, [conn.timezone_name]) @receiver(setting_changed) def clear_routers_cache(**kwargs): if kwargs['setting'] == 'DATABASE_ROUTERS': router.routers = ConnectionRouter().routers @receiver(setting_changed) def reset_template_engines(**kwargs): if kwargs['setting'] in { 'TEMPLATES', 'TEMPLATE_DIRS', 'ALLOWED_INCLUDE_ROOTS', 'TEMPLATE_CONTEXT_PROCESSORS', 'TEMPLATE_DEBUG', 'TEMPLATE_LOADERS', 'TEMPLATE_STRING_IF_INVALID', 'DEBUG', 'FILE_CHARSET', 'INSTALLED_APPS', }: from django.template import engines try: del engines.templates except AttributeError: pass engines._templates = None engines._engines = {} from django.template.engine import Engine Engine.get_default.cache_clear() @receiver(setting_changed) def clear_serializers_cache(**kwargs): if kwargs['setting'] == 'SERIALIZATION_MODULES': from django.core import serializers serializers._serializers = {} @receiver(setting_changed) def language_changed(**kwargs): if kwargs['setting'] in {'LANGUAGES', 'LANGUAGE_CODE', 'LOCALE_PATHS'}: from django.utils.translation import trans_real trans_real._default = None trans_real._active = threading.local() if kwargs['setting'] in {'LANGUAGES', 'LOCALE_PATHS'}: from django.utils.translation import trans_real trans_real._translations = {} trans_real.check_for_language.cache_clear() @receiver(setting_changed) def file_storage_changed(**kwargs): file_storage_settings = { 'DEFAULT_FILE_STORAGE', 'FILE_UPLOAD_DIRECTORY_PERMISSIONS', 'FILE_UPLOAD_PERMISSIONS', 'MEDIA_ROOT', 'MEDIA_URL', } if kwargs['setting'] in file_storage_settings: from django.core.files.storage import default_storage default_storage._wrapped = empty @receiver(setting_changed) def complex_setting_changed(**kwargs): if kwargs['enter'] and kwargs['setting'] in COMPLEX_OVERRIDE_SETTINGS: # Considering the current implementation of the signals framework, # stacklevel=5 shows the line containing the override_settings call. warnings.warn("Overriding setting %s can lead to unexpected behavior." % kwargs['setting'], stacklevel=5) @receiver(setting_changed) def root_urlconf_changed(**kwargs): if kwargs['setting'] == 'ROOT_URLCONF': from django.core.urlresolvers import clear_url_caches, set_urlconf clear_url_caches() set_urlconf(None) @receiver(setting_changed) def static_storage_changed(**kwargs): if kwargs['setting'] in { 'STATICFILES_STORAGE', 'STATIC_ROOT', 'STATIC_URL', }: from django.contrib.staticfiles.storage import staticfiles_storage staticfiles_storage._wrapped = empty @receiver(setting_changed) def static_finders_changed(**kwargs): if kwargs['setting'] in { 'STATICFILES_DIRS', 'STATIC_ROOT', }: from django.contrib.staticfiles.finders import get_finder get_finder.cache_clear() @receiver(setting_changed) def auth_password_validators_changed(**kwargs): if kwargs['setting'] == 'AUTH_PASSWORD_VALIDATORS': from django.contrib.auth.password_validation import get_default_password_validators get_default_password_validators.cache_clear()