Setting up Cotton with Django Template Partials

Both packages come with an auto-setup feature, but to get the packages working together we need to opt instead for the corresponding 'SimpleAppConfig' from each package:

INSTALLED_APPS = [
    "django_cotton.apps.SimpleAppConfig",
    "template_partials.apps.SimpleAppConfig",
]

This means we need to modify the TEMPLATES block ourselves to add the loaders and tags we need for each package. The loaders should be applied in a specific way so the packages work together, whilst still benefiting from Django's cached loader system.

TEMPLATES = [
    {
        "BACKEND": "django.template.backends.django.DjangoTemplates",
        "DIRS": [BASE_DIR / "templates"],
        "OPTIONS": {
            "loaders": [
                (
                    "template_partials.loader.Loader",
                    [
                        (
                            "django.template.loaders.cached.Loader",
                            [
                                "django_cotton.cotton_loader.Loader",
                                "django.template.loaders.filesystem.Loader",
                                "django.template.loaders.app_directories.Loader",
                            ],
                        )
                    ],
                )
            ],
            "context_processors": [
                # no changes
            ],
            "builtins": [
                "django_cotton.templatetags.cotton",
                "template_partials.templatetags.partials",
            ],
        },
    },
]

Because we're specifying loaders manually, Django prevents us from using the APPS_DIRS setting. This means we need to specify the path to the templates directory(s) manually.