import datetime
import re
+try:
+ from hashlib import md5
+except:
+ from md5 import new as md5
from urllib import quote_plus, urlencode
from django.db import models, IntegrityError, connection, transaction
from django.utils.http import urlquote as django_urlquote
import logging
+if not hasattr(cache, 'get_many'):
+ #put django 1.2 code here
+ pass
+
class LazyQueryList(object):
def __init__(self, model, items):
- self.model = model
self.items = items
+ self.model = model
def __getitem__(self, k):
- return self.model.objects.get(id=self.items[k])
+ return self.model.objects.get(id=self.items[k][0])
def __iter__(self):
for id in self.items:
- yield self.model.objects.get(id=id)
+ yield self.model.objects.get(id=id[0])
def __len__(self):
return len(self.items)
+class ToFetch(str):
+ pass
+
class CachedQuerySet(models.query.QuerySet):
+
def lazy(self):
- if len(self.query.extra) == 0:
- return LazyQueryList(self.model, list(self.values_list('id', flat=True)))
+ if not len(self.query.aggregates):
+ values_list = ['id']
+
+ if len(self.query.extra):
+ extra_keys = self.query.extra.keys()
+ values_list += extra_keys
+
+ return LazyQueryList(self.model, list(self.values_list(*values_list)))
else:
return self
+ def obj_from_datadict(self, datadict):
+ obj = self.model()
+ obj.__dict__.update(datadict)
+
+ if hasattr(obj, '_state'):
+ obj._state.db = 'default'
+
+ return obj
+
+ def _base_clone(self):
+ return self._clone(klass=models.query.QuerySet)
+
def get(self, *args, **kwargs):
- try:
- pk = [v for (k,v) in kwargs.items() if k in ('pk', 'pk__exact', 'id', 'id__exact'
- ) or k.endswith('_ptr__pk') or k.endswith('_ptr__id')][0]
- except:
- pk = None
+ key = self.model.infer_cache_key(kwargs)
- if pk is not None:
- key = self.model.cache_key(pk)
+ if key is not None:
obj = cache.get(key)
if obj is None:
- obj = super(CachedQuerySet, self).get(*args, **kwargs)
- obj.__class__.objects.cache_obj(obj)
+ obj = self._base_clone().get(*args, **kwargs)
+ obj.cache()
else:
- d = obj.__dict__
+ obj = self.obj_from_datadict(obj)
+ obj.reset_original_state()
return obj
- return super(CachedQuerySet, self).get(*args, **kwargs)
+ return self._base_clone().get(*args, **kwargs)
+
+ def _fetch_from_query_cache(self, key):
+ invalidation_key = self.model._get_cache_query_invalidation_key()
+ cached_result = cache.get_many([invalidation_key, key])
+
+ if not invalidation_key in cached_result:
+ self.model._set_query_cache_invalidation_timestamp()
+ return None
+
+ if (key in cached_result) and(cached_result[invalidation_key] < cached_result[key][0]):
+ return cached_result[key][1]
+
+ return None
+
+ def count(self):
+ cache_key = self.model._generate_cache_key("CNT:%s" % self._get_query_hash())
+ result = self._fetch_from_query_cache(cache_key)
+
+ if result is not None:
+ return result
+
+ result = super(CachedQuerySet, self).count()
+ cache.set(cache_key, (datetime.datetime.now(), result), 60 * 60)
+ return result
+
+ def iterator(self):
+ cache_key = self.model._generate_cache_key("QUERY:%s" % self._get_query_hash())
+ on_cache_query_attr = self.model.value_to_list_on_cache_query()
+
+ to_return = None
+ to_cache = {}
+
+ key_list = self._fetch_from_query_cache(cache_key)
+
+ if key_list is None:
+ if not len(self.query.aggregates):
+ values_list = [on_cache_query_attr]
+
+ if len(self.query.extra):
+ values_list += self.query.extra.keys()
+
+ key_list = [v[0] for v in self.values_list(*values_list)]
+ to_cache[cache_key] = (datetime.datetime.now(), key_list)
+ else:
+ to_return = list(super(CachedQuerySet, self).iterator())
+ to_cache[cache_key] = (datetime.datetime.now(), [row.__dict__[on_cache_query_attr] for row in to_return])
+
+ if (not to_return) and key_list:
+ row_keys = [self.model.infer_cache_key({on_cache_query_attr: attr}) for attr in key_list]
+ cached = cache.get_many(row_keys)
+
+ to_return = [
+ (ck in cached) and self.obj_from_datadict(cached[ck]) or ToFetch(key_list[i]) for i, ck in enumerate(row_keys)
+ ]
+
+ if len(cached) != len(row_keys):
+ to_fetch = [str(tr) for tr in to_return if isinstance(tr, ToFetch)]
+
+ fetched = dict([(str(r.__dict__[on_cache_query_attr]), r) for r in
+ models.query.QuerySet(self.model).filter(**{"%s__in" % on_cache_query_attr: to_fetch})])
+
+ to_return = [(isinstance(tr, ToFetch) and fetched[str(tr)] or tr) for tr in to_return]
+ to_cache.update(dict([(self.model.infer_cache_key({on_cache_query_attr: attr}), r._as_dict()) for attr, r in fetched.items()]))
+
+
+ if len(to_cache):
+ cache.set_many(to_cache, 60 * 60)
+
+ if to_return:
+ for row in to_return:
+ if hasattr(row, 'leaf'):
+ yield row.leaf
+ else:
+ yield row
+
+ def _get_query_hash(self):
+ return md5(str(self.query)).hexdigest()
+
-from action import Action
class CachedManager(models.Manager):
use_for_related_fields = True
- int_cache_re = re.compile('^_[\w_]+cache$')
def get_query_set(self):
return CachedQuerySet(self.model)
- def cache_obj(self, obj):
- int_cache_keys = [k for k in obj.__dict__.keys() if self.int_cache_re.match(k)]
- d = obj.__dict__
- for k in int_cache_keys:
- if not isinstance(obj.__dict__[k], Action):
- del obj.__dict__[k]
-
- cache.set(self.model.cache_key(obj.id), obj, 60 * 60)
-
def get_or_create(self, *args, **kwargs):
try:
return self.get(*args, **kwargs)
class DenormalizedField(object):
- def __init__(self, manager, **kwargs):
+ def __init__(self, manager, *args, **kwargs):
self.manager = manager
- self.filter = kwargs
+ self.filter = (args, kwargs)
def setup_class(self, cls, name):
- dict_name = '_%s_cache_' % name
+ dict_name = '_%s_dencache_' % name
def getter(inst):
val = inst.__dict__.get(dict_name, None)
if val is None:
- val = getattr(inst, self.manager).filter(**self.filter).count()
+ val = getattr(inst, self.manager).filter(*self.filter[0], **self.filter[1]).count()
inst.__dict__[dict_name] = val
- inst.__class__.objects.cache_obj(inst)
+ inst.cache()
return val
def reset_cache(inst):
inst.__dict__.pop(dict_name, None)
- inst.__class__.objects.cache_obj(inst)
+ inst.uncache()
cls.add_to_class(name, property(getter))
cls.add_to_class("reset_%s_cache" % name, reset_cache)
def __init__(self, *args, **kwargs):
super(BaseModel, self).__init__(*args, **kwargs)
- self._original_state = dict([(k, v) for k,v in self.__dict__.items() if not k in kwargs])
+ self.reset_original_state(kwargs.keys())
- @classmethod
- def cache_key(cls, pk):
- return '%s.%s:%s' % (settings.APP_URL, cls.__name__, pk)
+ def reset_original_state(self, reset_fields=None):
+ self._original_state = self._as_dict()
+
+ if reset_fields:
+ self._original_state.update(dict([(f, None) for f in reset_fields]))
def get_dirty_fields(self):
- missing = object()
- return dict([(k, self._original_state.get(k, None)) for k,v in self.__dict__.items()
- if self._original_state.get(k, missing) == missing or self._original_state[k] != v])
+ return [f.name for f in self._meta.fields if self._original_state[f.attname] != self.__dict__[f.attname]]
- def save(self, *args, **kwargs):
+ def _as_dict(self):
+ return dict([(name, getattr(self, name)) for name in
+ ([f.attname for f in self._meta.fields] + [k for k in self.__dict__.keys() if k.endswith('_dencache_')])
+ ])
+
+ def _get_update_kwargs(self):
+ return dict([
+ (f.name, getattr(self, f.name)) for f in self._meta.fields if self._original_state[f.attname] != self.__dict__[f.attname]
+ ])
+
+ def save(self, full_save=False, *args, **kwargs):
put_back = [k for k, v in self.__dict__.items() if isinstance(v, models.expressions.ExpressionNode)]
- super(BaseModel, self).save()
+
+ if hasattr(self, '_state'):
+ self._state.db = 'default'
+
+ if self.id and not full_save:
+ self.__class__.objects.filter(id=self.id).update(**self._get_update_kwargs())
+ else:
+ super(BaseModel, self).save()
if put_back:
try:
logging.error("Unable to read %s from %s" % (", ".join(put_back), self.__class__.__name__))
self.uncache()
- self._original_state = dict(self.__dict__)
+ self.reset_original_state()
+ self._set_query_cache_invalidation_timestamp()
self.cache()
- def cache(self):
- self.__class__.objects.cache_obj(self)
-
- def uncache(self):
- cache.delete(self.cache_key(self.pk))
-
- def delete(self):
- self.uncache()
- super(BaseModel, self).delete()
-
-
-class ActiveObjectManager(models.Manager):
- use_for_related_fields = True
- def get_query_set(self):
- return super(ActiveObjectManager, self).get_query_set().filter(canceled=False)
-
-class UndeletedObjectManager(models.Manager):
- def get_query_set(self):
- return super(UndeletedObjectManager, self).get_query_set().filter(deleted=False)
-
-class GenericContent(models.Model):
- content_type = models.ForeignKey(ContentType)
- object_id = models.PositiveIntegerField()
- content_object = generic.GenericForeignKey('content_type', 'object_id')
-
- class Meta:
- abstract = True
- app_label = 'forum'
-
-class MetaContent(BaseModel):
- node = models.ForeignKey('Node', null=True, related_name='%(class)ss')
-
- def __init__(self, *args, **kwargs):
- if 'content_object' in kwargs:
- kwargs['node'] = kwargs['content_object']
- del kwargs['content_object']
-
- super (MetaContent, self).__init__(*args, **kwargs)
-
- @property
- def content_object(self):
- return self.node.leaf
-
- class Meta:
- abstract = True
- app_label = 'forum'
-
-from user import User
-
-class UserContent(models.Model):
- user = models.ForeignKey(User, related_name='%(class)ss')
+ @classmethod
+ def _get_cache_query_invalidation_key(cls):
+ return cls._generate_cache_key("INV_TS")
- class Meta:
- abstract = True
- app_label = 'forum'
+ @classmethod
+ def _set_query_cache_invalidation_timestamp(cls):
+ cache.set(cls._get_cache_query_invalidation_key(), datetime.datetime.now(), 60 * 60 * 24)
+ for base in filter(lambda c: issubclass(c, BaseModel) and (not c is BaseModel), cls.__bases__):
+ base._set_query_cache_invalidation_timestamp()
-class DeletableContent(models.Model):
- deleted = models.BooleanField(default=False)
- deleted_at = models.DateTimeField(null=True, blank=True)
- deleted_by = models.ForeignKey(User, null=True, blank=True, related_name='deleted_%(class)ss')
+ @classmethod
+ def _generate_cache_key(cls, key, group=None):
+ if group is None:
+ group = cls.__name__
- active = UndeletedObjectManager()
+ return '%s:%s:%s' % (settings.APP_URL, group, key)
- class Meta:
- abstract = True
- app_label = 'forum'
+ def cache_key(self):
+ return self._generate_cache_key(self.id)
- def mark_deleted(self, user):
- if not self.deleted:
- self.deleted = True
- self.deleted_at = datetime.datetime.now()
- self.deleted_by = user
- self.save()
- return True
- else:
- return False
+ @classmethod
+ def value_to_list_on_cache_query(cls):
+ return 'id'
- def unmark_deleted(self):
- if self.deleted:
- self.deleted = False
- self.save()
- return True
- else:
- return False
+ @classmethod
+ def infer_cache_key(cls, querydict):
+ try:
+ pk = [v for (k,v) in querydict.items() if k in ('pk', 'pk__exact', 'id', 'id__exact'
+ ) or k.endswith('_ptr__pk') or k.endswith('_ptr__id')][0]
-mark_canceled = django.dispatch.Signal(providing_args=['instance'])
+ return cls._generate_cache_key(pk)
+ except:
+ return None
-class CancelableContent(models.Model):
- canceled = models.BooleanField(default=False)
+ def cache(self):
+ cache.set(self.cache_key(), self._as_dict(), 60 * 60)
- def cancel(self):
- if not self.canceled:
- self.canceled = True
- self.save()
- mark_canceled.send(sender=self.__class__, instance=self)
- return True
-
- return False
+ def uncache(self):
+ cache.delete(self.cache_key())
- class Meta:
- abstract = True
- app_label = 'forum'
+ def delete(self):
+ self.uncache()
+ self._set_query_cache_invalidation_timestamp()
+ super(BaseModel, self).delete()
+from user import User
from node import Node, NodeRevision, NodeManager
+from action import Action
projects / osqa.git / blobdiff