39 lines
1.2 KiB
Python
39 lines
1.2 KiB
Python
import datetime, os
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from src import PollHook, utils
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EXPIRATION = 60 # 1 minute
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class LockFile(PollHook.PollHook):
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def __init__(self, filename: str):
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self._filename = filename
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self._next_lock = None
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def available(self):
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now = utils.datetime.utcnow()
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if os.path.exists(self._filename):
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with open(self._filename, "r") as lock_file:
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timestamp_str = lock_file.read().strip().split(" ", 1)[0]
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timestamp = utils.datetime.parse.iso8601(timestamp_str)
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if (now-timestamp).total_seconds() < EXPIRATION:
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return False
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return True
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def lock(self):
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with open(self._filename, "w") as lock_file:
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last_lock = utils.datetime.utcnow()
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lock_file.write("%s" % utils.datetime.format.iso8601(last_lock))
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self._next_lock = last_lock+datetime.timedelta(
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seconds=EXPIRATION/2)
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def next(self):
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return max(0,
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(self._next_lock-utils.datetime.utcnow()).total_seconds())
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def call(self):
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self.lock()
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def unlock(self):
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if os.path.isfile(self._filename):
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os.remove(self._filename)
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