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   
 31 -class ZeoPoolBase(ZenDaemon): 
 32      """ 
 33      A multi-threaded daemon that maintains a pool of zeo connections 
 34      that it can hand out to its worker threads. 
 35      """ 
 36   
 37   
 38 -    def __init__(self, noopts=0, app=None, keeproot=False): 
 39          ZenDaemon.__init__(self, noopts, keeproot) 
 40          self.opendb() 
 41          self.openconn = self.getPoolSize() 
 42   
 43   
 44 -    def getConnection(self, path=None): 
 45          """Return a connection from the connection pool. If path is passed 
 46          return the object that the path points to. 
 47          """ 
 48          try: 
 49              self.poollock.acquire() 
 50              if not self.is_connected(): 
 51                  self.opendb() 
 52              connection=self.db.open() 
 53              root=connection.root() 
 54              app=root['Application'] 
 55              self._getContext(app) 
 56              app._p_jar.sync() 
 57              if path: 
 58                  return app.getObjByPath(path) 
 59              else: 
 60                  return app 
 61              self.openconn -= 1 
 62          finally: 
 63              self.poollock.release() 
 64   
 65   
 66 -    def opendb(self): 
 67          addr = (self.options.host, self.options.port) 
 68          self._storage=ClientStorage.ClientStorage(addr) 
 69          self.db=DB(self._storage) 
 70          self.poollock = Lock() 
 71   
 72   
 73 -    def closedb(self): 
 74          """Close all connections in both free an inuse pools. 
 75          """ 
 76          self.db.close() 
 77          self.db = None 
 78          self._storage = None 
 79   
 80   
 81 -    def is_connected(self): 
 82          """Are we connected to zeo. 
 83          """ 
 84          return not self._storage or self._storage.is_connected() 
 85   
 86   
 87 -    def getPoolSize(self): 
 88          """Return the target max pool size for this database. 
 89          """ 
 90          return self.db.getPoolSize() 
 91   
 92   
 93 -    def available(self): 
 94          """Return the number of available connection in our pool. 
 95          """ 
 96          if self.db._pools: 
 97              pool = self.db._pools[''] # trunk version pool 
 98              return len(pool.available) 
 99          return 0 
100   
101   
102 -    def _getContext(self, app): 
103          resp = HTTPResponse(stdout=None) 
104          env = { 
105              'SERVER_NAME':'localhost', 
106              'SERVER_PORT':'8080', 
107              'REQUEST_METHOD':'GET' 
108              } 
109          req = HTTPRequest(None, env, resp) 
110          app.__of__(RequestContainer(REQUEST = req)) 
111          return app 
112   
113   
114 -    def buildOptions(self): 
115          """basic options setup sub classes can add more options here""" 
116          ZenDaemon.buildOptions(self) 
117          self.parser.add_option('--host', 
118                      dest="host",default="localhost", 
119                      help="hostname of zeo server") 
120          self.parser.add_option('--port', 
121                      dest="port",type="int", default=8100, 
122                      help="port of zeo server") 
123