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This package provides decorators that will try to acquire lock before calling decorated function.

Installation

pip install lockorator

Usage

This package provides two flavours of lock decorators: redis and asyncio. Both flavours have the same api.

Package lockorator.asyncio provides asyncio lock decorators, also compatible with trio.

Package lockorator.redis provides redis lock decorators.

To use redis locks, set LOCKORATOR_REDIS_URL in your environment:

export LOCKORATOR_REDIS_URL="redis://localhost:6379"

API

lock_or_exit

Decorator. Before decorated function starts, try to acquire lock with specified identifier. If lock is acquired successfully, proceed executing the function. Otherwise, return immediately. The id argument can contain templated string, wich will be rendered with args and kwargs, passed to the function.

Example:

from lockorator.asyncio import lock_or_exit

@lock_or_exit('lock_work_{}')
def workwork(x):
    pass

workwork(3)  # Will try to acquire lock 'lock_work_3'

lock_wait

Decorator. Before decorated function starts, try to acquire lock with specified identifier, waiting for waittime seconds if needed. If lock is acquired successfully, proceed executing the function. Otherwise, raise lockorator.TimeoutError. The id argument can contain templated string, wich will be rendered with args and kwargs, passed to the function.

Example:

from lockorator.redis import lock_wait

@lock_wait('lock_work_{}', waittime=4)
def workwork(x):
    pass

workwork(3)  # Will try to acquire lock 'lock_work_3' for 4 seconds