Redis-Based Distributed Mutex (with TTL)

                  class RedisMutex
  def initialize(redis: Redis.current)
    @redis = redis
  end

  def with_lock(key, ttl: 60)
    token = SecureRandom.uuid
    ok = @redis.set(key, token, nx: true, ex: ttl)
    return false unless ok

    yield
  ensure
    release(key, token)
  end

  private

  def release(key, token)
    lua = <<~LUA
      if redis.call('get', KEYS[1]) == ARGV[1] then
        return redis.call('del', KEYS[1])
      else
        return 0
      end
    LUA
    @redis.eval(lua, keys: [key], argv: [token])
  end
end