Doc/includes/mp_newtype.py

   1 #
   2 # This module shows how to use arbitrary callables with a subclass of
   3 # `BaseManager`.
   4 #
   5 # Copyright (c) 2006-2008, R Oudkerk
   6 # All rights reserved.
   7 #
   8
   9 from multiprocessing import freeze_support
  10 from multiprocessing.managers import BaseManager, BaseProxy
  11 import operator
  12
  13 ##
  14
  15 class Foo(object):
  16     def f(self):
  17         print 'you called Foo.f()'
  18     def g(self):
  19         print 'you called Foo.g()'
  20     def _h(self):
  21         print 'you called Foo._h()'
  22
  23 # A simple generator function
  24 def baz():
  25     for i in xrange(10):
  26         yield i*i
  27
  28 # Proxy type for generator objects
  29 class GeneratorProxy(BaseProxy):
  30     _exposed_ = ('next', '__next__')
  31     def __iter__(self):
  32         return self
  33     def next(self):
  34         return self._callmethod('next')
  35     def __next__(self):
  36         return self._callmethod('__next__')
  37
  38 # Function to return the operator module
  39 def get_operator_module():
  40     return operator
  41
  42 ##
  43
  44 class MyManager(BaseManager):
  45     pass
  46
  47 # register the Foo class; make `f()` and `g()` accessible via proxy
  48 MyManager.register('Foo1', Foo)
  49
  50 # register the Foo class; make `g()` and `_h()` accessible via proxy
  51 MyManager.register('Foo2', Foo, exposed=('g', '_h'))
  52
  53 # register the generator function baz; use `GeneratorProxy` to make proxies
  54 MyManager.register('baz', baz, proxytype=GeneratorProxy)
  55
  56 # register get_operator_module(); make public functions accessible via proxy
  57 MyManager.register('operator', get_operator_module)
  58
  59 ##
  60
  61 def test():
  62     manager = MyManager()
  63     manager.start()
  64
  65     print '-' * 20
  66
  67     f1 = manager.Foo1()
  68     f1.f()
  69     f1.g()
  70     assert not hasattr(f1, '_h')
  71     assert sorted(f1._exposed_) == sorted(['f', 'g'])
  72
  73     print '-' * 20
  74
  75     f2 = manager.Foo2()
  76     f2.g()
  77     f2._h()
  78     assert not hasattr(f2, 'f')
  79     assert sorted(f2._exposed_) == sorted(['g', '_h'])
  80
  81     print '-' * 20
  82
  83     it = manager.baz()
  84     for i in it:
  85         print '<%d>' % i,
  86     print
  87
  88     print '-' * 20
  89
  90     op = manager.operator()
  91     print 'op.add(23, 45) =', op.add(23, 45)
  92     print 'op.pow(2, 94) =', op.pow(2, 94)
  93     print 'op.getslice(range(10), 2, 6) =', op.getslice(range(10), 2, 6)
  94     print 'op.repeat(range(5), 3) =', op.repeat(range(5), 3)
  95     print 'op._exposed_ =', op._exposed_
  96
  97 ##
  98
  99 if __name__ == '__main__':
 100     freeze_support()
 101     test()