-- Copyright (C) Yichun Zhang (agentzh)
--
-- This is an aggregator for various concrete traffic limiter instances
-- (like instances of the resty.limit.req, resty.limit.count and
-- resty.limit.conn classes).
local max = math.max
local _M = {
_VERSION = '0.08'
}
-- the states table is user supplied. each element stores the 2nd return value
-- of each limiter if there is no error returned. for resty.limit.req, the state
-- is the "excess" value (i.e., the number of excessive requests each second),
-- and for resty.limit.conn, the state is the current concurrency level
-- (including the current new connection).
function _M.combine(limiters, keys, states)
local n = #limiters
local max_delay = 0
for i = 1, n do
local lim = limiters[i]
local delay, err = lim:incoming(keys[i], i == n)
if not delay then
return nil, err
end
if i == n then
if states then
states[i] = err
end
max_delay = delay
end
end
for i = 1, n - 1 do
local lim = limiters[i]
local delay, err = lim:incoming(keys[i], true)
if not delay then
for j = 1, i - 1 do
-- we intentionally ignore any errors returned below.
limiters[j]:uncommit(keys[j])
end
limiters[n]:uncommit(keys[n])
return nil, err
end
if states then
states[i] = err
end
max_delay = max(max_delay, delay)
end
return max_delay
end
return _M