testing/web-platform/tests/tools/docker/retry.py

   1 #! /usr/bin/env python
   2 import argparse
   3 import subprocess
   4 import time
   5 import sys
   6
   7
   8 def get_args():
   9     parser = argparse.ArgumentParser()
  10     parser.add_argument("--delay", action="store", type=float, default=3, help="Initial delay before retry, in seconds")
  11     parser.add_argument("--count", action="store", type=int, default=5, help="Total number of tries")
  12     parser.add_argument("--factor", action="store", type=float, default=2, help="Exponential backoff factor")
  13     parser.add_argument("cmd", nargs=argparse.REMAINDER)
  14     return parser
  15
  16
  17 def iter_range(n):
  18     i = 0
  19     while i < n:
  20         yield i
  21         i += 1
  22
  23
  24 def main():
  25     args = get_args().parse_args()
  26
  27     if not args.cmd:
  28         print("No command supplied")
  29         sys.exit(1)
  30
  31     retcode = None
  32
  33     for n in iter_range(args.count):
  34         try:
  35             print("Running %s [try %d/%d]" % (" ".join(args.cmd), (n+1), args.count))
  36             subprocess.check_call(args.cmd)
  37         except subprocess.CalledProcessError as e:
  38             retcode = e.returncode
  39         else:
  40             print("Command succeeded")
  41             retcode = 0
  42             break
  43
  44         if args.factor == 0:
  45             wait_time = (n+1) * args.delay
  46         else:
  47             wait_time = args.factor**n * args.delay
  48         if n < args.count - 1:
  49             print("Command failed, waiting %s seconds to retry" % wait_time)
  50             time.sleep(wait_time)
  51         else:
  52             print("Command failed, out of retries")
  53
  54     sys.exit(retcode)
  55
  56
  57 if __name__ == "__main__":
  58     main()