Source Code for Module ZenUtils.ZeoPoolBase

  1  ########################################################################### 
  2  # 
  3  # This program is part of Zenoss Core, an open source monitoring platform. 
  4  # Copyright (C) 2007, Zenoss Inc. 
  5  # 
  6  # This program is free software; you can redistribute it and/or modify it 
  7  # under the terms of the GNU General Public License version 2 as published by 
  8  # the Free Software Foundation. 
  9  # 
 10  # For complete information please visit: http://www.zenoss.com/oss/ 
 11  # 
 12  ########################################################################### 
 13   
 14  __doc__="""ZeoPoolBase 
 15   
 16  $Id: ZC.py,v 1.9 2004/02/16 17:19:31 edahl Exp $""" 
 17   
 18  __version__ = "$Revision: 1.9 $"[11:-2] 
 19   
 20  from threading import Lock 
 21   
 22  from ZEO import ClientStorage 
 23  from ZODB import DB 
 24  from ZPublisher.HTTPRequest import HTTPRequest 
 25  from ZPublisher.HTTPResponse import HTTPResponse 
 26  from ZPublisher.BaseRequest import RequestContainer 
 27   
 28  from ZenDaemon import ZenDaemon 
 29   
 30  from Products.ZenUtils.Utils import unused 
 31   
 32 -class ZeoPoolBase(ZenDaemon): 
 33      """ 
 34      A multi-threaded daemon that maintains a pool of zeo connections 
 35      that it can hand out to its worker threads. 
 36      """ 
 37   
 38   
 39 -    def __init__(self, noopts=0, app=None, keeproot=False): 
 40          ZenDaemon.__init__(self, noopts, keeproot) 
 41          unused(app) 
 42          self.opendb() 
 43          self.openconn = self.getPoolSize() 
 44   
 45   
 46 -    def getConnection(self, path=None): 
 47          """Return a connection from the connection pool. If path is passed 
 48          return the object that the path points to. 
 49          """ 
 50          try: 
 51              self.poollock.acquire() 
 52              if not self.is_connected(): 
 53                  self.opendb() 
 54              connection=self.db.open() 
 55              root=connection.root() 
 56              app=root['Application'] 
 57              self._getContext(app) 
 58              app._p_jar.sync() 
 59              if path: 
 60                  return app.getObjByPath(path) 
 61              else: 
 62                  return app 
 63              self.openconn -= 1 
 64          finally: 
 65              self.poollock.release() 
 66   
 67   
 68 -    def opendb(self): 
 69          addr = (self.options.host, self.options.port) 
 70          self._storage=ClientStorage.ClientStorage(addr) 
 71          self.db=DB(self._storage) 
 72          self.poollock = Lock() 
 73   
 74   
 75 -    def closedb(self): 
 76          """Close all connections in both free an inuse pools. 
 77          """ 
 78          self.db.close() 
 79          self.db = None 
 80          self._storage = None 
 81   
 82   
 83 -    def is_connected(self): 
 84          """Are we connected to zeo. 
 85          """ 
 86          return not self._storage or self._storage.is_connected() 
 87   
 88   
 89 -    def getPoolSize(self): 
 90          """Return the target max pool size for this database. 
 91          """ 
 92          return self.db.getPoolSize() 
 93   
 94   
 95 -    def available(self): 
 96          """Return the number of available connection in our pool. 
 97          """ 
 98          if self.db._pools: 
 99              pool = self.db._pools[''] # trunk version pool 
100              return len(pool.available) 
101          return 0 
102   
103   
104 -    def _getContext(self, app): 
105          resp = HTTPResponse(stdout=None) 
106          env = { 
107              'SERVER_NAME':'localhost', 
108              'SERVER_PORT':'8080', 
109              'REQUEST_METHOD':'GET' 
110              } 
111          req = HTTPRequest(None, env, resp) 
112          app.__of__(RequestContainer(REQUEST = req)) 
113          return app 
114   
115   
116 -    def buildOptions(self): 
117          """basic options setup sub classes can add more options here""" 
118          ZenDaemon.buildOptions(self) 
119          self.parser.add_option('--host', 
120                      dest="host",default="localhost", 
121                      help="hostname of zeo server") 
122          self.parser.add_option('--port', 
123                      dest="port",type="int", default=8100, 
124                      help="port of zeo server") 
125