Source Code for Module AEEvent.ChildrenChange

 1  ''' 
 2  Defines an L{AEEvent} indicating that a child has been added/removed to an  
 3  accessible. 
 4   
 5  @author: Brett Clippingdale 
 6  @author: Peter Parente 
 7  @organization: IBM Corporation 
 8  @copyright: Copyright (c) 2005, 2007 IBM Corporation 
 9  @license: The BSD License 
10   
11  All rights reserved. This program and the accompanying materials are made  
12  available under the terms of the BSD license which accompanies 
13  this distribution, and is available at 
14  U{http://www.opensource.org/licenses/bsd-license.php} 
15  ''' 
16   
17  import Base 
18  from AEInterfaces import * 
19   
20 -class ChildrenChange(Base.AccessEngineEvent): 
21    ''' 
22    Event that fires on children changes. 
23     
24    This class registers its name and whether it should be monitored by default in 
25    an L{AEMonitor} using the L{Base.registerEventType} function 
26    when this module is first imported. The L{AEMonitor} can use this 
27    information to build its menus. 
28   
29    @ivar por: The L{POR} of the parent 
30    @type por: L{POR} 
31    @ivar added: True when a child is added, False when removed 
32    @type added: boolean 
33    @ivar child_por: The L{POR} of added/removed child 
34    @type child_por: L{POR} 
35    ''' 
36    Base.registerEventType('ChildrenChange', False) 
37 -  def __init__(self, por, added, child_por, **kwargs): 
38      ''' 
39      Stores the L{POR}, event name, first and last children (if any) associated 
40      with the event.    
41      ''' 
42      Base.AccessEngineEvent.__init__(self, **kwargs) 
43      self.por = por 
44      self.added = added 
45      self.child_por = child_por 
46       
47 -  def __str__(self): 
48      ''' 
49      Returns a human readable representation of this event including its name, 
50      its L{POR}, its event name, and its associated values. 
51       
52      @return: Information about this event 
53      @rtype: string 
54      ''' 
55      name = Base.AccessEngineEvent.__str__(self) 
56      return '%s:\n\tPOR: %s\n\tadded: %s\n\tchild_por: %s\n' \ 
57             %(name, self.por, self.added, self.child_por) 
58     
59 -  def execute(self, tier_manager, **kwargs): 
60      ''' 
61      Contacts the L{TierManager} so it can manage the children change event. 
62       
63      @param tier_manager: TierManager that will handle the event 
64      @type tier_manager: L{TierManager} 
65      @param kwargs: Packed references to other managers not of interest here 
66      @type kwargs: dictionary 
67      @return: Always True to indicate the event executed properly 
68      @rtype: boolean 
69      ''' 
70      tier_manager.manageEvent(self) 
71      return True 
72   
73 -  def getDataForTask(self): 
74      ''' 
75      Fetches data out of this L{AEEvent.ChildrenChange} for use by a 
76      L{Task.ChildrenTask}. 
77       
78      @return: Dictionary of parameters to be passed to a 
79        L{Task.ChildrenTask} as follows: 
80          - por:  The L{POR} of the accessible parent 
81          - added: True when a child is added, False when removed 
82          - child_por: The L{POR} of added/removed child 
83      ''' 
84      if self.child_por.incomplete: 
85        self.child_por = IPORFactory(self.child_por).create() 
86      return {'por':self.getPOR(), 'added':self.added, 'child_por':self.child_por} 
87