[Python] Wagtail: requests to the root URL of a multilang website cause error when DEBUG=False

I am building a bilingual Wagtail website, following directions in the Wagtail documentation.

With DEBUG = True in the website settings, all works as expected : one can navigate between english and french versions of the website, and the locale is reflected in the /en/ or /fr/ prefix in the URL. When requesting the root URL of the site https://example.com, the english home page is rendered and the URL has the prefix /en/ added automatically.

With DEBUG = False, requesting the root URL results in a server error. Adding the /en/ prefix manually still works.

The (rather long) backtrace of the error is here.

The website settings are the almost default ones, with additional multi-language configuration:

MIDDLEWARE = [
"django.contrib.sessions.middleware.SessionMiddleware",
"django.middleware.locale.LocaleMiddleware",
"django.middleware.common.CommonMiddleware",
"django.middleware.csrf.CsrfViewMiddleware",
"django.contrib.auth.middleware.AuthenticationMiddleware",
"django.contrib.messages.middleware.MessageMiddleware",
"django.middleware.clickjacking.XFrameOptionsMiddleware",
"django.middleware.security.SecurityMiddleware",
"wagtail.contrib.redirects.middleware.RedirectMiddleware",
]
USE_I18N = True
USE_L10N = True
WAGTAIL_I18N_ENABLED = True
USE_TZ = True
WAGTAILSIMPLETRANSLATION_SYNC_PAGE_TREE = True


The url configuration is:

urlpatterns = [
path("admin/", include(wagtailadmin_urls)),
path("documents/", include(wagtaildocs_urls)),
path("search/", search_views.search, name="search"),
] + i18n_patterns(
path('search/', search_views.search, name='search'),
path("", include(wagtail_urls)),
)


If needed, the full website settings are here.

Note that requesting the admin page at https://example.com/admin causes the same server error when DEBUG = False. Requesting https://example.com/admin/ works though... I tried changing Wagtail versions to v6.4.1 and v7.0.2, but it didn't change anything.

Continue reading...