Source Code for Module pyspark.broadcast

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17   
18  """ 
19  >>> from pyspark.context import SparkContext 
20  >>> sc = SparkContext('local', 'test') 
21  >>> b = sc.broadcast([1, 2, 3, 4, 5]) 
22  >>> b.value 
23  [1, 2, 3, 4, 5] 
24   
25  >>> from pyspark.broadcast import _broadcastRegistry 
26  >>> _broadcastRegistry[b.bid] = b 
27  >>> from cPickle import dumps, loads 
28  >>> loads(dumps(b)).value 
29  [1, 2, 3, 4, 5] 
30   
31  >>> sc.parallelize([0, 0]).flatMap(lambda x: b.value).collect() 
32  [1, 2, 3, 4, 5, 1, 2, 3, 4, 5] 
33   
34  >>> large_broadcast = sc.broadcast(list(range(10000))) 
35  """ 
36  # Holds broadcasted data received from Java, keyed by its id. 
37  _broadcastRegistry = {} 
38   
39   
40 -def _from_id(bid): 
41      from pyspark.broadcast import _broadcastRegistry 
42      if bid not in _broadcastRegistry: 
43          raise Exception("Broadcast variable '%s' not loaded!" % bid) 
44      return _broadcastRegistry[bid] 
45   
46   
47 -class Broadcast(object): 
48      """ 
49      A broadcast variable created with 
50      L{SparkContext.broadcast()<pyspark.context.SparkContext.broadcast>}. 
51      Access its value through C{.value}. 
52      """ 
53   
54 -    def __init__(self, bid, value, java_broadcast=None, pickle_registry=None): 
55          """ 
56          Should not be called directly by users -- use 
57          L{SparkContext.broadcast()<pyspark.context.SparkContext.broadcast>} 
58          instead. 
59          """ 
60          self.value = value 
61          self.bid = bid 
62          self._jbroadcast = java_broadcast 
63          self._pickle_registry = pickle_registry 
64   
65 -    def __reduce__(self): 
66          self._pickle_registry.add(self) 
67          return (_from_id, (self.bid, )) 
68