lock cache key during update

This commit is contained in:
j 2016-02-26 17:09:01 +05:30
parent a026d42428
commit 75afa33a6e
3 changed files with 17 additions and 2 deletions

View File

@ -1,3 +1,4 @@
from threading import Lock
import time
class Cache(dict):
@ -5,6 +6,12 @@ class Cache(dict):
def __init__(self, ttl=10):
self._ttl = ttl
self._added = {}
self._lock = {}
def lock(self, key):
if key not in self._lock:
self._lock[key] = Lock()
self._lock[key].acquire()
def get(self, key):
now = time.time()
@ -12,12 +19,18 @@ class Cache(dict):
if value < now:
self._added.pop(k, None)
self.pop(k, None)
self._lock.pop(k, None)
if key in self._lock:
self._lock[key].acquire()
return dict.get(self, key)
def set(self, key, value, ttl=None):
ttl = ttl or self._ttl
self._added[key] = time.time() + ttl
dict.__setitem__(self, key, value)
q = self._lock.pop(key, None)
if q:
q.release()
def delete(self, key):
if key in self._added:

View File

@ -3,7 +3,6 @@
import json
import hashlib
import os
import unicodedata
from sqlalchemy.orm import load_only
from sqlalchemy.sql.expression import text
@ -52,11 +51,13 @@ def find(data):
key = 'group:' + hashlib.sha1(json.dumps(_keydata, sort_keys=True).encode('utf-8')).hexdigest()
g = state.cache.get(key)
if g is None:
state.cache.lock(key)
items = q['qs'].options(load_only('id'))
qs = models.Find.query.filter_by(key=q['group'])
if items.first():
qs = qs.filter(models.Find.item_id.in_(items))
for f in qs.values('value', 'findvalue', 'sortvalue'):
values = list(qs.values('value', 'findvalue', 'sortvalue'))
for f in values:
value = f[0]
findvalue = f[1]
sortvalue = f[2]

View File

@ -72,6 +72,7 @@ def findTitles(data):
key = 'title:' + hashlib.sha1(json.dumps(_keydata, sort_keys=True).encode('utf-8')).hexdigest()
titles = state.cache.get(key)
if titles is None:
state.cache.lock(key)
response['items'] = []
_titles = {}
for i in q['qs']: