from django.conf import settings from django.contrib.sites.models import Site from django.db import models from django.db.models import loading from django.utils.translation import ugettext_lazy as _ from keyedcache import cache_key, cache_get, cache_set, NotCachedError from keyedcache.models import CachedObjectMixin from livesettings.overrides import get_overrides import logging log = logging.getLogger('configuration.models') __all__ = ['SettingNotSet', 'Setting', 'LongSetting', 'find_setting'] def _safe_get_siteid(site): if not site: try: site = Site.objects.get_current() siteid = site.id except: siteid = settings.SITE_ID else: siteid = site.id return siteid def find_setting(group, key, site=None): """Get a setting or longsetting by group and key, cache and return it.""" siteid = _safe_get_siteid(site) setting = None use_db, overrides = get_overrides(siteid) ck = cache_key('Setting', siteid, group, key) if use_db: try: setting = cache_get(ck) except NotCachedError, nce: if loading.app_cache_ready(): try: setting = Setting.objects.get(site__id__exact=siteid, key__exact=key, group__exact=group) except Setting.DoesNotExist: # maybe it is a "long setting" try: setting = LongSetting.objects.get(site__id__exact=siteid, key__exact=key, group__exact=group) except LongSetting.DoesNotExist: pass cache_set(ck, value=setting) else: grp = overrides.get(group, None) if grp and grp.has_key(key): val = grp[key] setting = ImmutableSetting(key=key, group=group, value=val) log.debug('Returning overridden: %s', setting) if not setting: raise SettingNotSet(key, cachekey=ck) return setting class SettingNotSet(Exception): def __init__(self, k, cachekey=None): self.key = k self.cachekey = cachekey self.args = [self.key, self.cachekey] class SettingManager(models.Manager): def get_query_set(self): all = super(SettingManager, self).get_query_set() siteid = _safe_get_siteid(None) return all.filter(site__id__exact=siteid) class ImmutableSetting(object): def __init__(self, group="", key="", value="", site=1): self.site = site self.group = group self.key = key self.value = value def cache_key(self, *args, **kwargs): return cache_key('OverrideSetting', self.site, self.group, self.key) def delete(self): pass def save(self, *args, **kwargs): pass def __repr__(self): return "ImmutableSetting: %s.%s=%s" % (self.group, self.key, self.value) class Setting(models.Model, CachedObjectMixin): site = models.ForeignKey(Site, verbose_name=_('Site')) group = models.CharField(max_length=100, blank=False, null=False) key = models.CharField(max_length=100, blank=False, null=False) value = models.CharField(max_length=255, blank=True) objects = SettingManager() def __nonzero__(self): return self.id is not None def cache_key(self, *args, **kwargs): return cache_key('Setting', self.site, self.group, self.key) def delete(self): self.cache_delete() super(Setting, self).delete() def save(self, force_insert=False, force_update=False): try: site = self.site except Site.DoesNotExist: self.site = Site.objects.get_current() super(Setting, self).save(force_insert=force_insert, force_update=force_update) self.cache_set() class Meta: unique_together = ('site', 'group', 'key') class LongSettingManager(models.Manager): def get_query_set(self): all = super(LongSettingManager, self).get_query_set() siteid = _safe_get_siteid(None) return all.filter(site__id__exact=siteid) class LongSetting(models.Model, CachedObjectMixin): """A Setting which can handle more than 255 characters""" site = models.ForeignKey(Site, verbose_name=_('Site')) group = models.CharField(max_length=100, blank=False, null=False) key = models.CharField(max_length=100, blank=False, null=False) value = models.TextField(blank=True) objects = LongSettingManager() def __nonzero__(self): return self.id is not None def cache_key(self, *args, **kwargs): # note same cache pattern as Setting. This is so we can look up in one check. # they can't overlap anyway, so this is moderately safe. At the worst, the # Setting will override a LongSetting. return cache_key('Setting', self.site, self.group, self.key) def delete(self): self.cache_delete() super(LongSetting, self).delete() def save(self, force_insert=False, force_update=False): try: site = self.site except Site.DoesNotExist: self.site = Site.objects.get_current() super(LongSetting, self).save(force_insert=force_insert, force_update=force_update) self.cache_set() class Meta: unique_together = ('site', 'group', 'key')