del(deleteTargets) {
		this.metrics.increment(METRIC.MOLECULER_CACHER_DEL_TOTAL);
		const timeEnd = this.metrics.timer(METRIC.MOLECULER_CACHER_DEL_TIME);

		deleteTargets = Array.isArray(deleteTargets) ? deleteTargets : [deleteTargets];
		const keysToDelete = deleteTargets.map(key => this.prefix + key);
		this.logger.debug(`DELETE ${keysToDelete}`);
		return this.client
			.del(keysToDelete)
			.then(res => {
				timeEnd();
				return res;
			})
			.catch(err => {
				timeEnd();
				this.logger.error(`Redis 'del' error. Key: ${keysToDelete}`, err);
				throw err;
			});
	}
Delete a key from cache

@param {string|Array<string>} deleteTargets
@returns {Promise}

@memberof Cacher