NXLog Redis output module  sends data to a Redis server with the RPUSH command allowing only to change the Redis key ( = database).

RPUSH inserts all the specified values at the tail of the list stored at key

I suggest that the Redis command has to be implemented as a parameter and to support at least the LPUSH.

LPUSH inserts all the specified values at the head of the list stored at key

There are clients that support only retreiving data from the head. The most usual case is to send data to Redis with LPUSH and then have Logstash poll record from Redis with LPOP.

Thank you.