Store increments in Redis

[alexsnaps]

Currently we store decrements in Redis. We first store the limit's threshold on miss and then decrement

Current SCRIPT_UPDATE_COUNTER script:

local set_res = redis.call('set', KEYS[1], ARGV[1], 'EX', ARGV[2], 'NX')
redis.call('incrby', KEYS[1], - ARGV[3])
if set_res then
    redis.call('sadd', KEYS[2], KEYS[1])
end

The idea is to completely decouple the counter from the limit and only store what happened, i.e. increments from 0
Something along these lines:

local c = redis.call('incrby', KEYS[1], ARGV[2])
if c == ARGV[2] then
  redis.call('expire', KEYS[1], ARGV[1], 'NX')
  redis.call('sadd', KEYS[2], KEYS[1])
end
return c

Let's introduce this as another script and try leveraging it in our both our (Async)CounterStorages