24 lines
769 B
Python
24 lines
769 B
Python
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import contextlib
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class JournalManager(object):
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def __init__(self, save_checkpoint):
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self._save_checkpoint = save_checkpoint
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self._outbound_queue = []
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self._processing = False
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def queue_outbound(self, fn, *args, **kwargs):
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assert self._processing
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self._outbound_queue.append((fn, args, kwargs))
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@contextlib.contextmanager
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def process(self):
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assert not self._processing
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assert not self._outbound_queue
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self._processing = True
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yield # process inbound messages, change state, queue outbound
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self._save_checkpoint()
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for (fn, args, kwargs) in self._outbound_queue:
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fn(*args, **kwargs)
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self._outbound_queue[:] = []
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self._processing = False
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