Q: How can I set the expire time in Redis' ruby client when using mapped_mset? I am trying to use 
redis.mapped_mset({ "f1" => "v1", "f2" => "v2" })

to set multiple keys into Redis and I can not set expire time at the same time.
The only way to set expire time to to use this:
set(key, value, options = {})

or
expire(key, seconds)

I have to call many times and this is not what I want to see.
Are there any other ways to solve this problem?

A: Redis itself does not support multiple setting with an expiration parameter. Redis#mapped_set is a syntactic sugar to call mset and mset itself is a syntactic sugar to transactionally call subsequent set many times.
So, the only thing you need is to wrap subsequent calls to set(... ex:...) into a transaction with Redis#multi.

A: You can write wrapper method to set a list and add expiration. Use redis.multi to wrap it into trasactional module. 
def set_list(list, expire_in = 10)
  redis.multi do
    list.each{ |k, v| redis.set(k,v, ex: expire_in)}
  end
end

