annotate python/example/waiter.py @ 896:83618049c2ff

py3
author Jeff Hammel <k0scist@gmail.com>
date Fri, 11 Feb 2022 09:33:38 -0800
parents 9f85111f3dee
children
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1 #!/usr/bin/env python
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2
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3 """
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4 wait for a process writing to stdout to keep an
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5 (e.g.) ssh connection alive
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6 """
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7
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8 import subprocess
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9 import sys
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10 import time
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11
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12 KEEPALIVE = 300 # s
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13 SLEEP = 1
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14
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15
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16 def main(args=sys.argv[1:]):
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17 """CLI"""
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18
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19 last = start = time.time()
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20 proc = subprocess.Popen(args)
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21
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22 while proc.poll() is None:
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23 if time.time() - last > KEEPALIVE:
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24 last = time.time()
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25 print ("[{} s] waiting for process: {}".format(last-start, subprocess.list2cmdline(args)))
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26 sys.stdout.flush()
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27 exit(proc.poll())
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28
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29 if __name__ == '__main__':
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30 main()