How to expire gelocations on redis

Question

I am using geo-support on Redis.

Adding new geolocations this way:

"GEOADD" "report-geo-set" "30.52439985197" "50.56539003041" "john"

I want to expire john key from report-geo-set after X hours.

Any suggestions doing that?

Thank you, ray.

Answer 1

Not possible with built-in commands. Keep in mind that geo-support based on zset and your question is look`s like "How to use TTL for individual keys in ZSET".

You may use something like that:

1. Add "john" to additional special timeout ZSET with time() + X hours score.
2. From time to time run script/worker which get all obsolete keys from timeout zset and execute ZREM for your "john" key.

Example of given suggestion. Add items:

MULTI
GEOADD report-geo-set 30.52439985197 50.56539003041 john
ZADD geo-timeout 1452600528 john //1452600528 is unix time stamp current + X hours 
EXEC

Clean up script called from time to time (with LUA):

local currentTime = redis.call('TIME');
local list = redis.call('ZRANGEBYSCORE', 'geo-timeout', 0, currentTime[0]);
local keysRemoved = 0;
for i, name in ipairs(list) do
    redis.call('ZREM', 'geo-timeout', name);
    redis.call('ZREM', 'report-geo-set', name);
    keysRemoved = keysRemoved + 1;
end
return keysRemoved;