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分散ロック

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from django.core.cache import cache

with cache.lock("somekey"):
    do_some_thing()

redis-py:

デッドロック

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import django.db.backends.utils
from django.db import OperationalError
import time

original = django.db.backends.utils.CursorWrapper.execute

def execute_wrapper(*args, **kwargs):
    attempts = 0
    while attempts < 3:
        try:
            return original(*args, **kwargs)
        except OperationalError as e:
            code = e.args[0]
            if attempts == 2 or code != 1213:
                raise e
            attempts += 1
            time.sleep(0.2)

django.db.backends.utils.CursorWrapper.execute = execute_wrapper