31 lines
1.0 KiB
Python
31 lines
1.0 KiB
Python
import sys
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# NOTE: this class is required to be able to use print/log commands and have them flush to stdout and stderr immediately
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# without wrapper stdout and stderr, when using `childProcess.stdout.on('data', ...)` in NodeJS script, we never get
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# any events fired until the process exits. However, force flushing the streams does fire the callbacks in NodeJS.
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# this class forces stream writes to be flushed immediately
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class ImmediateFlushingStreamWrapper:
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def __init__(self, stream):
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self.stream = stream
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# force write to flush immediately
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def write(self, data):
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self.stream.write(data)
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self.stream.flush()
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# force writelines to flush immediately
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def writelines(self, lines):
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self.stream.writelines(lines)
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self.stream.flush()
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def __getattr__(self, attr):
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return getattr(self.stream, attr)
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# wrap stdout and stderr with our custom wrapper
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sys.stdout = ImmediateFlushingStreamWrapper(sys.stdout)
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sys.stderr = ImmediateFlushingStreamWrapper(sys.stderr)
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