Source Code for Module gofer.rmi.tracker

  1  # Copyright (c) 2012 Red Hat, Inc. 
  2  # 
  3  # This software is licensed to you under the GNU General Public 
  4  # License as published by the Free Software Foundation; either version 
  5  # 2 of the License (GPLv2) or (at your option) any later version. 
  6  # There is NO WARRANTY for this software, express or implied, 
  7  # including the implied warranties of MERCHANTABILITY, 
  8  # NON-INFRINGEMENT, or FITNESS FOR A PARTICULAR PURPOSE. You should 
  9  # have received a copy of GPLv2 along with this software; if not, see 
 10  # http://www.gnu.org/licenses/old-licenses/gpl-2.0.txt. 
 11   
 12  """ 
 13  Request tracker classes. 
 14  """ 
 15   
 16  from threading import RLock 
 17   
 18  from gofer import Singleton, synchronized 
 19   
 20   
 21 -class Tracker: 
 22      """ 
 23      Request tracker used to track information about 
 24      active RMI requests. 
 25      @ivar __all: All known requests by serial number. 
 26      @type __all: set 
 27      @ivar __cancelled: Cancelled requests. 
 28      @type __cancelled: set 
 29      @ivar __mutex: The object mutex. 
 30      @type __mutex: RLock 
 31      """ 
 32   
 33      __metaclass__ = Singleton 
 34   
 35 -    def __init__(self): 
 36          self.__all = dict() 
 37          self.__cancelled = set() 
 38          self.__mutex = RLock() 
 39   
 40      @synchronized 
 41 -    def add(self, sn, locator): 
 42          """ 
 43          Add a serial number (make know) for tracking. 
 44          @param sn: An RMI serial number. 
 45          @type sn: str 
 46          @param locator:  The object used by find() to match 
 47              on RMI requests. 
 48          @type locator: object 
 49          """ 
 50          self.__all[sn] = locator 
 51   
 52      @synchronized 
 53 -    def find(self, criteria): 
 54          """ 
 55          Find serial numbers matching user defined (any) data. 
 56          @param criteria: The object used to match RMI requests. 
 57          @type criteria: L{gofer.rmi.criteria.Criteria} 
 58          @return: The list of matching serial numbers. 
 59          @rtype: list 
 60          """ 
 61          matched = [] 
 62          for sn, locator in self.__all.items(): 
 63              if criteria.match(locator): 
 64                  matched.append(sn) 
 65          return matched 
 66   
 67      @synchronized 
 68 -    def cancel(self, sn): 
 69          """ 
 70          Notify the tracker that an RMI request has been cancelled. 
 71          @param sn: An RMI serial number. 
 72          @type sn: str 
 73          @return: The cancelled serial number (if not already cancelled). 
 74          @rtype: str 
 75          """ 
 76          if sn in self.__all: 
 77              if sn not in self.__cancelled: 
 78                  self.__cancelled.add(sn) 
 79                  return sn 
 80          else: 
 81              raise Exception, 'serial number (%s), not-found' % sn 
 82   
 83      @synchronized 
 84 -    def cancelled(self, sn): 
 85          """ 
 86          Get whether an RMI request has been cancelled. 
 87          @param sn: An RMI serial number. 
 88          @type sn: str 
 89          @return: True if cancelled. 
 90          @rtype: bool 
 91          """ 
 92          return sn in self.__cancelled 
 93   
 94      @synchronized 
 95 -    def remove(self, sn): 
 96          """ 
 97          Discontinue tracking an RMI request. 
 98          @param sn: An RMI serial number. 
 99          @type sn: str 
100          """ 
101          self.__all.pop(sn) 
102          if sn in self.__cancelled: 
103              self.__cancelled.remove(sn) 
104