Source code for ferrosoft.apps.ferrobase.middleware.cache

#  Copyright (c) 2025 Ferrosoft GmbH. All rights reserved.
from asgiref.sync import iscoroutinefunction, markcoroutinefunction
from django.conf import settings
from django.http import HttpResponse




class CacheControlMiddleware:
    """Middleware that ensures every response carries a ``Cache-Control`` header.

    If the upstream view already set the header, it is left untouched.
    Otherwise the value is taken from ``settings.CACHE_CONTROL``, falling back
    to ``"no-store"`` so sensitive platform responses are never cached by
    default.
    """

    async_capable = True
    sync_capable = False

    _HEADER = "Cache-Control"
    _CONFIG = "CACHE_CONTROL"
    _DEFAULT = "no-store"

    def __init__(self, get_response):
        self.get_response = get_response
        if iscoroutinefunction(self.get_response):
            markcoroutinefunction(self)

    async def __call__(self, request):
        response: HttpResponse = await self.get_response(request)
        if self._HEADER not in response.headers:
            response.headers["Cache-Control"] = getattr(
                settings, self._CONFIG, self._DEFAULT
            )
        return response