django-dbtemplates/dbtemplates/utils/cache.py

75 lines
2.3 KiB
Python

from django.core.cache import get_cache
from django.contrib.sites.models import Site
from django.template.defaultfilters import slugify
from dbtemplates.conf import settings
def get_cache_backend():
return get_cache(settings.DBTEMPLATES_CACHE_BACKEND)
cache = get_cache_backend()
def get_cache_key(name, site_pk=None):
if site_pk is None:
site_pk = Site.objects.get_current().pk
return 'dbtemplates::%s::%s' % (slugify(name), site_pk)
def get_cache_notfound_key(name, site_pk=None):
return get_cache_key(name, site_pk) + '::notfound'
def remove_notfound_key(instance):
# Remove notfound key as soon as we save the template.
cache.delete(get_cache_notfound_key(instance.name))
def set_and_return(cache_key, content, display_name):
# Save in cache backend explicitly if manually deleted or invalidated
if cache:
cache.set(cache_key, content)
return (content, display_name)
def add_template_to_cache(instance, **kwargs):
"""
Called via Django's signals to cache the templates, if the template
in the database was added or changed.
"""
remove_cached_template(instance)
remove_notfound_key(instance)
cache.set(get_cache_key(instance.name), instance.content)
def invalidate_cache_for_sites(sender, instance, action, reverse,
model, pk_set, **kwargs):
if action != 'post_add':
return
if isinstance(instance, Site):
# model is dbtemplates.models.Template
site = instance
for template in model.objects.all():
if template.pk in pk_set:
cache.delete(get_cache_notfound_key(template.name, site.pk))
else:
cache.delete(get_cache_key(template.name, site.pk))
else:
# instance is of type dbtempaltes.models.Template
# model is django.contrib.sites.models.Site
template = instance
for site in model.objects.all():
if site.pk in pk_set:
cache.delete(get_cache_notfound_key(template.name, site.pk))
else:
cache.delete(get_cache_key(template.name, site.pk))
def remove_cached_template(instance, **kwargs):
"""
Called via Django's signals to remove cached templates, if the template
in the database was changed or deleted.
"""
cache.delete(get_cache_key(instance.name))