Source Code for Module ClusterShell.MsgTree

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  3  #  Contributor: Stephane THIELL <stephane.thiell@cea.fr> 
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 33  # $Id: MsgTree.py 126 2009-07-13 21:35:07Z st-cea $ 
 34   
 35  """ 
 36  MsgTree 
 37   
 38  ClusterShell message tree classes. 
 39  """ 
 40   
 41  from sets import Set 
 42   
 43 -class MsgTreeElem: 
 44      """ 
 45      Helper class used to build a messages tree. Advantages are: 
 46      (1) low memory consumption especially on a cluster when all nodes 
 47      return similar messages, 
 48      (2) gathering of messages is done (almost) automatically. 
 49      """ 
 50 -    def __init__(self, msg=None, parent=None): 
 51          """ 
 52          Initialize message tree element. 
 53          """ 
 54          # structure 
 55          self.parent = parent 
 56          self.children = {} 
 57          # content 
 58          self.msg = msg 
 59          self.sources = None 
 60      
 61 -    def __iter__(self): 
 62          """ 
 63          Iterate over tree key'd elements. 
 64          """ 
 65          estack = [ self ] 
 66   
 67          while len(estack) > 0: 
 68              elem = estack.pop() 
 69              if len(elem.children) > 0: 
 70                  estack += elem.children.values() 
 71              if elem.sources and len(elem.sources) > 0: 
 72                  yield elem 
 73       
 74 -    def _add_source(self, source): 
 75          """ 
 76          Add source tuple (worker, key) to this element. 
 77          """ 
 78          if not self.sources: 
 79              self.sources = source.copy() 
 80          else: 
 81              self.sources.union_update(source) 
 82       
 83 -    def _remove_source(self, source): 
 84          """ 
 85          Remove a source tuple (worker, key) from this element. 
 86          It's used when moving it to a child. 
 87          """ 
 88          if self.sources: 
 89              self.sources.difference_update(source) 
 90           
 91 -    def add_msg(self, source, msg): 
 92          """ 
 93          A new message line is coming, add it to the tree. 
 94          source is a tuple identifying the message source 
 95          """ 
 96          if self.sources and len(self.sources) == 1: 
 97              # do it quick when only one source is attached 
 98              src = self.sources 
 99              self.sources = None 
100          else: 
101              # remove source from parent (self) 
102              src = Set([ source ]) 
103              self._remove_source(src) 
104   
105          # add msg elem to child 
106          elem = self.children.setdefault(msg, self.__class__(msg, self)) 
107          # add source to elem 
108          elem._add_source(src) 
109          return elem 
110   
111 -    def message(self): 
112          """ 
113          Get the whole message buffer from this tree element. 
114          """ 
115          msg = "" 
116   
117          # no msg in root element 
118          if self.msg is None: 
119              return msg 
120           
121          # build list of msg (reversed by design) 
122          rmsgs = [self.msg] 
123          parent = self.parent 
124          while parent and parent.msg is not None: 
125              rmsgs.append(parent.msg) 
126              parent = parent.parent 
127   
128          # reverse the list 
129          rmsgs.reverse() 
130   
131          # concat buffers 
132          return '\n'.join(rmsgs) 
133