Redis: how to EXPIRE a set?

Question

PHP

Task: logging the site on redis
My solution: all logs are written in redis with a TTL of 30 minutes. every 10 minutes a script is run that gets the averages for 10 minutes and stores them in MySQL.
In Redis, keys are UNIX TIMESTAMP and Set is made up of events. happened in this second.
Problem: I can't put EXPIRE on a Set that is constantly updated.
those.
RPUSH 'a' 'b'
EXPIRE 'a' 120
RPUSH 'a' 'c'
EXPIRE 'a' 120
LRANGE 'a' 0 -1 => 'c'
because any RPUSH after EXPIRE kills the previous value.

Maybe I didn't see something?

Answer 1

oops, sorry, I completely misunderstood the question - forget the previous answer :)
answer 2: radish has a TTL function