Use MemcacheDict from MemcacheTool to support Transaction Manager

git-svn-id: https://svn.erp5.org/repos/public/erp5/trunk@29064 20353a03-c40f-0410-a6d1-a30d3c3de9de

product/ERP5Type/CachePlugins/DistributedRamCache.py

@@ -30,7 +30,7 @@
 """
 Memcached based cache plugin.
 """
-from thread import get_ident
+from threading import local
 from zLOG import LOG, WARNING
 from BaseCache import BaseCache
 from BaseCache import CacheEntry
@@ -40,11 +40,12 @@ from base64 import encodestring
 
 try:
   import memcache
+  from Products.ERP5Type.Tool.MemcachedTool import MemcachedDict
 except ImportError:
   LOG('DistributedRamCache', 0, 'unable to import memcache')
 
 ## global ditionary containing connection objects
-connection_pool = {}
+connection_pool = local()
 
 _MARKER = []
 
@@ -74,35 +75,14 @@ class DistributedRamCache(BaseCache):
     ## "MemCached: while expecting 'STORED', got unexpected response 'END'"
     ## messages in log files and can sometimes can block the thread. 
     ## For the moment we create a new conn object for every thread.
-    global connection_pool
-    thread_id = get_ident()
-
-    memcache_conn = connection_pool.get(thread_id, None)
-    if memcache_conn is not None:
     try:
-        stats = memcache_conn.get_stats()
-      except IndexError:
-        stats = ()
-      if not len(stats) or not len(stats[0][1]):
-        # create a new connection if the existing connection seems
-        # dead.
-        # XXX Since python-memcached does not raise an exception in such
-        # a case, we check here by calling get_stats(), but it will take
-        # a bit more time for each getCacheStorage() call.
-        LOG('DistributedRamCache', WARNING, 'the existing connection seems dead. a new connection will be created.')
-        memcache_conn.disconnect_all()
-        memcache_conn = None
-    if memcache_conn is None:
-      ## we don't have memcache_conn for this thread
-      memcache_conn = memcache.Client(self._servers.split('\n'),
-                              debug=self._debug_level,
+      dictionary = connection_pool.memcached_dict
+    except AttributeError:
+      dictionary = MemcachedDict(self._servers.split('\n'),
                                  server_max_key_length=self._server_max_key_length,
                                  server_max_value_length=self._server_max_value_length)
-      connection_pool[thread_id] = memcache_conn
-      return memcache_conn
-    else:
-      ## we have memcache_conn for this thread
-      return memcache_conn
+      connection_pool.memcached_dict = dictionary
+    return dictionary
 
   def checkAndFixCacheId(self, cache_id, scope):
     ## memcached doesn't support namespaces (cache scopes) so to "emmulate"
@@ -138,7 +118,7 @@ class DistributedRamCache(BaseCache):
     cache_storage = self.getCacheStorage()
     cache_id = self.checkAndFixCacheId(cache_id, scope)
     cache_entry = CacheEntry(value, cache_duration, calculation_time)
-    cache_storage.set(cache_id, cache_entry, cache_duration)
+    cache_storage.set(cache_id, cache_entry)
     self.markCacheMiss()
 
   def expireOldCacheEntries(self, forceCheck = False):
@@ -155,7 +135,7 @@ class DistributedRamCache(BaseCache):
   def delete(self, cache_id, scope):
     cache_storage = self.getCacheStorage()
     cache_id = self.checkAndFixCacheId(cache_id, scope)
-    cache_storage.delete(cache_id)
+    del cache_storage[cache_id]
 
   def has_key(self, cache_id, scope):
     cache_storage = self.getCacheStorage()