Function check_dependencies

django/contrib/admin/checks.py:56–174

Check that the admin's dependencies are correctly installed.

(**kwargs)

def check_dependencies(**kwargs):
    """
    Check that the admin's dependencies are correctly installed.
    """
    from django.contrib.admin.sites import all_sites

    if not apps.is_installed("django.contrib.admin"):
        return []
    errors = []
    app_dependencies = (
        ("django.contrib.contenttypes", 401),
        ("django.contrib.auth", 405),
        ("django.contrib.messages", 406),
    )
    for app_name, error_code in app_dependencies:
        if not apps.is_installed(app_name):
            errors.append(
                checks.Error(
                    "'%s' must be in INSTALLED_APPS in order to use the admin "
                    "application." % app_name,
                    id="admin.E%d" % error_code,
                )
            )
    for engine in engines.all():
        if isinstance(engine, DjangoTemplates):
            django_templates_instance = engine.engine
            break
    else:
        django_templates_instance = None
    if not django_templates_instance:
        errors.append(
            checks.Error(
                "A 'django.template.backends.django.DjangoTemplates' instance "
                "must be configured in TEMPLATES in order to use the admin "
                "application.",
                id="admin.E403",
            )
        )
    else:
        if (
            "django.contrib.auth.context_processors.auth"
            not in django_templates_instance.context_processors
            and _contains_subclass(
                "django.contrib.auth.backends.ModelBackend",
                settings.AUTHENTICATION_BACKENDS,
            )
        ):
            errors.append(
                checks.Error(
                    "'django.contrib.auth.context_processors.auth' must be "
                    "enabled in DjangoTemplates (TEMPLATES) if using the default "
                    "auth backend in order to use the admin application.",
                    id="admin.E402",
                )
            )
        if (
            "django.contrib.messages.context_processors.messages"
            not in django_templates_instance.context_processors