39 lines
1.1 KiB
Python
39 lines
1.1 KiB
Python
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from threading import Thread
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from queue import Queue, Empty
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class NonBlockingStreamReader:
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def __init__(self, stream):
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'''
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stream: the stream to read from.
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Usually a process' stdout or stderr.
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'''
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self._s = stream
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self._q = Queue()
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def _populateQueue(stream, queue):
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'''
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Collect lines from 'stream' and put them in 'quque'.
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'''
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while True:
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line = stream.readline()
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if line:
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queue.put(line)
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else:
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raise UnexpectedEndOfStream
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self._t = Thread(target = _populateQueue,
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args = (self._s, self._q))
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self._t.daemon = True
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self._t.start() #start collecting lines from the stream
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def readline(self, timeout = None):
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try:
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return self._q.get(block = timeout is not None,
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timeout = timeout)
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except Empty:
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return None
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class UnexpectedEndOfStream(Exception): pass
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