Django 清除特定视图缓存
Django 只提供了清楚所有缓存的入口，而未提供清楚某个特定视图缓存的入口。由于需求需要，笔者研究Django缓存机制，找到了清除特定视图缓存的方法。
记录如下（以下代码均是按照Django源码所写）：
构造构造缓存的键，供查找缓存
def get_cache_key(request, url, cache, key_prefix=None):
"""
构造缓存的键，供查找缓存
:param request:
:param url:完整路由
:param key_prefix:如果设置，则按照设置，如果未设置，则按照默认
:param cache:
:return: 视图内容缓存，视图请求头缓存
"""
if key_prefix is None:
key_prefix = settings.CACHE_MIDDLEWARE_KEY_PREFIX
url = hashlib.md5(force_bytes(iri_to_uri(url)))
cache_key = 'views.decorators.cache.cache_header.%s.%s' % (
key_prefix, url.hexdigest())
cache_key_header = _i18n_cache_key_suffix(request, cache_key)
headerlist = cache.get(cache_key_header)
if headerlist is not None:
ctx = hashlib.md5()
for header in headerlist:
value = request.META.get(header)
if value is not None:
ctx.update(force_bytes(value))
cache_key = 'views.decorators.cache.cache_page.%s.%s.%s.%s' % (
key_prefix, 'GET', url.hexdigest(), ctx.hexdigest())
return _i18n_cache_key_suffix(request, cache_key), cache_key_header
else:
return None, None
用于删除缓存的视图
from django.conf import settings
from django.core.cache import caches
from the_van.utils.utils import get_cache_key
class SomeViewSet(ModelViewSet):
queryset = Some.objects.all()
serializer_class = SomeSerializer
@action(detail=False, methods=['get'])
def clear(self, request):
# 要清理缓存的路由
url = request.query_params.get('url', None)
if url is None:
return JsonResponse({'message': '请传入参数', 'status': 404, 'data': {}})
cache_alias = settings.CACHE_MIDDLEWARE_ALIAS
key_prefix = settings.CACHE_MIDDLEWARE_KEY_PREFIX
cache = caches[cache_alias]
url = request.META['wsgi.url_scheme'] + '://' + request.META['HTTP_HOST'] + '/' + 'video/'
cache_key, cache_key_header = get_cache_key(request, url, cache, key_prefix=key_prefix)
if cache_key is None:
return JsonResponse({'message': '没有对应缓存', 'status': 200, 'data': {}})
cache.delete(cache_key)
cache.delete(cache_key_header)
return JsonResponse({'message': '清除缓存成功', 'status': 200, 'data': {}})
