modules/presence/redis-lua/presence-reassociate.lua

   1 local key_socket_user = KEYS[1];
   2 local key_user_lock = KEYS[2];
   3 local key_troupe_users = KEYS[3];
   4 local key_prev_troupe_users = KEYS[4];
   5
   6 local user_id = ARGV[1];
   7 local socket_id = ARGV[2];
   8 local troupe_id = ARGV[3];
   9 local known_prev_troupe_id = ARGV[4];
  10 local is_eyeballs_on = ARGV[5];
  11
  12 if redis.call("EXISTS", key_socket_user) ~= 1 then
  13         -- socket does not exist
  14         return { 0 }
  15 end
  16
  17 redis.call("INCR", key_user_lock);
  18 redis.call("EXPIRE", key_user_lock, 10);
  19
  20 local prev_troupe_id = redis.call("HGET", key_socket_user, "tid")
  21 local was_eyeballs_on = redis.call("HGET", key_socket_user, "eb") == "1"
  22
  23 local user_in_troupe_count = -1
  24 local user_in_prev_troupe_count = -1
  25
  26 -- Theres a very small chance the troupe has changed this the app server
  27 -- queried for the existing value. Double check and don't process
  28 -- this request if that's the case
  29 if known_prev_troupe_id ~= prev_troupe_id then
  30         return { 0 }
  31 end
  32
  33 -- Eyeballs off the previous troupe
  34 if was_eyeballs_on and prev_troupe_id then
  35         user_in_prev_troupe_count = redis.call("ZINCRBY", key_prev_troupe_users, -1, user_id)
  36         redis.call("ZREMRANGEBYSCORE", key_prev_troupe_users, '-inf', '0')
  37 end
  38
  39 if troupe_id and troupe_id ~= "" then
  40         -- If we are reassociating with a new troupe
  41         redis.call("HSET", key_socket_user, "tid", troupe_id)
  42
  43         if is_eyeballs_on and user_id and user_id ~= "" then
  44                 -- Set eyeballs status for non-anonymous users
  45                 user_in_troupe_count = redis.call("ZINCRBY", key_troupe_users, 1, user_id)
  46                 redis.call("HSET", key_socket_user, "eb", 1)
  47         else
  48                 -- Clear eyeballs if off or anonymous
  49                 redis.call("HDEL", key_socket_user, "eb")
  50         end
  51 else
  52         -- No longer associated with a troupe
  53         redis.call("HDEL", key_socket_user, "tid", "eb")
  54 end
  55
  56 return { 1, user_in_troupe_count, user_in_prev_troupe_count  }