import redis
from redis.lock import Lock

import config
from constants import common as consts


redis_client = redis.StrictRedis(config.REDIS_HOST, config.REDIS_PORT)


def get_key(key: str) -> str:
    """Compose a Redis key.

    Args:
        key (str): Key.

    Returns:
        str: Complete key constructed by concatenated prefix + key.

    """
    return f'{consts.APP_NAME}/{key}'


def get_redis_lock() -> Lock:
    """Get redis lock

    Returns:
        Lock: Redis lock.

    """
    return redis_client.lock(get_key('lock'), timeout=config.REDIS_LOCK_TTL)