Source Code for Module Task.Base

  1  ''' 
  2  Defines the base class for all L{Task}s. 
  3   
  4  @author: Peter Parente 
  5  @author: Larry Weiss 
  6  @organization: IBM Corporation 
  7  @copyright: Copyright (c) 2005, 2007 IBM Corporation 
  8  @license: The BSD License 
  9   
 10  All rights reserved. This program and the accompanying materials are made  
 11  available under the terms of the BSD license which accompanies 
 12  this distribution, and is available at 
 13  U{http://www.opensource.org/licenses/bsd-license.php} 
 14  ''' 
 15  import Tools, UIElement, UIRegistrar 
 16   
 17  default_types = [] 
 18  all_types = [] 
 19   
 20 -def registerTaskType(name, default): 
 21    ''' 
 22    Called once by every L{Task} class to register itself for buffering and  
 23    filtering by an L{AEMonitor}. 
 24     
 25    @param name: Name of the L{Task} 
 26    @type name: string 
 27    @param default: Should this L{Task} be buffered by default? 
 28    @type default: boolean 
 29    ''' 
 30    global default_types 
 31    global all_types 
 32    all_types.append(name) 
 33    if default: 
 34      default_types.append(name) 
 35       
 36 -def getDefaults(): 
 37    ''' 
 38    Suggests the default L{Task}s to be monitored. 
 39     
 40    @return: Names of defaults to monitor 
 41    @rtype: list of string 
 42    ''' 
 43    return default_types   
 44     
 45 -def getNames(): 
 46    ''' 
 47    Gets the names of all the L{Task} types. 
 48     
 49    @return: List of all L{Task} names 
 50    @rtype: list of string 
 51    ''' 
 52    return all_types 
 53   
 54 -class Task(Tools.All, UIElement.UIE): 
 55    ''' 
 56    Most base class for all L{Task}s that execute in a L{Perk}. Stores a  
 57    string identifying a particular class instance. Implements L{UIElement} 
 58    to provide information to the user about its purpose even though it is not 
 59    managed by the L{UIRegistrar}. 
 60     
 61    @ivar ident: Programmatic identifier for this L{Task} 
 62    @type ident: string 
 63    '''  
 64 -  def __init__(self, ident): 
 65      ''' 
 66      Stores the L{Task} identifier. 
 67       
 68      @param ident: Programmatic identifier 
 69      @type ident: string 
 70      ''' 
 71      Tools.All.__init__(self) 
 72      self.ident = ident 
 73       
 74 -  def execute(self, **kwargs): 
 75      ''' 
 76      Executes this L{Task} in response to an event. Called by  
 77      L{Tier.Tier._executeTask}. 
 78       
 79      @param kwargs: Dictionary containing parameters passed to a task. 
 80      @type kwargs: dictionary  
 81      @return: Should processing continue? Always returns True by default. 
 82      @rtype: boolean 
 83      ''' 
 84      return True 
 85     
 86 -  def update(self, **kwargs): 
 87      ''' 
 88      Allows this L{Task} to update itself in response to an event that was  
 89      consumed by another L{Task} that executed before it. Called by  
 90      L{Tier.Tier._executeTask}. 
 91       
 92      @param kwargs: Dictionary containing parameters passed to a task. 
 93      @type kwargs: dictionary  
 94      ''' 
 95      pass 
 96     
 97 -  def getIdentity(self): 
 98      ''' 
 99      Gets the unique string identity assigned to this L{Task}. 
100       
101      @return: Identity of this L{Task} 
102      @rtype: string 
103      @raise ValueError: When L{ident} is None, meaning this L{Task} has no  
104        unique identity 
105      ''' 
106      if self.ident is None: 
107        raise ValueError 
108      return self.ident 
109     
110 -  def getPerk(self): 
111      ''' 
112      Gets the L{Perk} in which this L{Task} was registered. 
113       
114      @return: Reference to the L{Perk} 
115      @rtype: L{Perk} 
116      ''' 
117      return self.perk 
118     
119 -  def getPath(self): 
120      ''' 
121      @return: Absolute path location of the module containing the implementor 
122        of this interface 
123      @rtype: string 
124      ''' 
125      return UIRegistrar.getPath(self.perk.getClassName()) 
126