DRF-Extension cache ignoring query parameters

Question

I am using drf-extension for caching my APIs. But it is not working as expected with cache_response decorator.

It caches the response for say /api/get-cities/?country=india . But when I hit /api/get-cities/?country=usa, I get the same response.

Here is the sample code:

settings.py

CACHES = {
   "default": {
       "BACKEND": "django_redis.cache.RedisCache",
       "LOCATION": "redis://127.0.0.1:6379/0",
       "OPTIONS": {
           "CLIENT_CLASS": "django_redis.client.DefaultClient"
       },
       "KEY_PREFIX": "city"
   }
}

REST_FRAMEWORK_EXTENSIONS = {
   'DEFAULT_USE_CACHE': 'default',
   'DEFAULT_CACHE_RESPONSE_TIMEOUT': 86400,
}

views.py

class GetCities(APIView):

    @cache_response()
    def get(self, request):
        country = request.GET.get("country", "")
        return get_cities_function(country)

Please help with this.

Answer 1

I was able to find a solution for the problem. I created my own keys in redis with the combination of api name and parameter name(in my case country). So when API is hit with query parameters, I check if a key exists corresponding to that, if it exists then cached response is returned.

class GetCities(APIView):

    def calculate_cache_key(self, view_instance, view_method, request, args, kwargs):
        api = view_instance.get_view_name().replace(' ', '')
        return "api:" + api + "country:" + str(request.GET.get("country", ""))

    @cache_response(key_func='calculate_cache_key')
    def get(self, request):
        country = request.GET.get("country", "")
        return get_cities_function(country)