27 lines
835 B
Python
27 lines
835 B
Python
class LazyPluggable(object):
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"""A pluggable backend loaded lazily based on some value."""
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def __init__(self, pivot, **backends):
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self.__backends = backends
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self.__pivot = pivot
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self.__backend = None
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def __get_backend(self):
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if not self.__backend:
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print self.__backends.values()
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backend_name = 'sqlalchemy'
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backend = self.__backends[backend_name]
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if isinstance(backend, tuple):
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name = backend[0]
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fromlist = backend[1]
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else:
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name = backend
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fromlist = backend
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self.__backend = __import__(name, None, None, fromlist)
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return self.__backend
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def __getattr__(self, key):
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backend = self.__get_backend()
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return getattr(backend, key)
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