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32 lines
995 B
Python
32 lines
995 B
Python
# Copyright (C) 2011 Jesus Leganes "piranna", piranna@gmail.com
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#
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# This module is part of python-sqlparse and is released under
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# the BSD License: http://www.opensource.org/licenses/bsd-license.php.
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from types import GeneratorType
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class Pipeline(list):
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"""Pipeline to process filters sequentially"""
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def __call__(self, stream):
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"""Run the pipeline
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Return a static (non generator) version of the result
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"""
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# Run the stream over all the filters on the pipeline
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for filter in self:
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# Functions and callable objects (objects with '__call__' method)
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if callable(filter):
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stream = filter(stream)
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# Normal filters (objects with 'process' method)
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else:
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stream = filter.process(None, stream)
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# If last filter return a generator, staticalize it inside a list
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if isinstance(stream, GeneratorType):
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return list(stream)
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return stream
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