ingress-nginx-helm/rootfs/etc/nginx/lua/balancer/sticky.lua
2019-03-04 10:34:48 -05:00

104 lines
2.7 KiB
Lua

local balancer_resty = require("balancer.resty")
local resty_chash = require("resty.chash")
local util = require("util")
local ck = require("resty.cookie")
local math = require("math")
local _M = balancer_resty:new({ factory = resty_chash, name = "sticky" })
local DEFAULT_COOKIE_NAME = "route"
function _M.cookie_name(self)
return self.cookie_session_affinity.name or DEFAULT_COOKIE_NAME
end
function _M.new(self, backend)
local nodes = util.get_nodes(backend.endpoints)
local o = {
instance = self.factory:new(nodes),
traffic_shaping_policy = backend.trafficShapingPolicy,
alternative_backends = backend.alternativeBackends,
cookie_session_affinity = backend["sessionAffinityConfig"]["cookieSessionAffinity"]
}
setmetatable(o, self)
self.__index = self
return o
end
local function set_cookie(self, value)
local cookie, err = ck:new()
if not cookie then
ngx.log(ngx.ERR, err)
end
local cookie_path = self.cookie_session_affinity.path
if not cookie_path then
cookie_path = ngx.var.location_path
end
local cookie_data = {
key = self:cookie_name(),
value = value,
path = cookie_path,
httponly = true,
secure = ngx.var.https == "on",
}
if self.cookie_session_affinity.expires and self.cookie_session_affinity.expires ~= "" then
cookie_data.expires = ngx.cookie_time(ngx.time() + tonumber(self.cookie_session_affinity.expires))
end
if self.cookie_session_affinity.maxage and self.cookie_session_affinity.maxage ~= "" then
cookie_data.max_age = tonumber(self.cookie_session_affinity.maxage)
end
local ok
ok, err = cookie:set(cookie_data)
if not ok then
ngx.log(ngx.ERR, err)
end
end
function _M.balance(self)
local cookie, err = ck:new()
if not cookie then
ngx.log(ngx.ERR, "error while initializing cookie: " .. tostring(err))
return
end
local key = cookie:get(self:cookie_name())
if not key then
key = string.format("%s.%s.%s", ngx.now(), ngx.worker.pid(), math.random(999999))
if self.cookie_session_affinity.locations then
local locs = self.cookie_session_affinity.locations[ngx.var.host]
if locs ~= nil then
for _, path in pairs(locs) do
if ngx.var.location_path == path then
set_cookie(self, key)
break
end
end
end
end
end
return self.instance:find(key)
end
function _M.sync(self, backend)
balancer_resty.sync(self, backend)
-- Reload the balancer if any of the annotations have changed.
local changed = not util.deep_compare(
self.cookie_session_affinity,
backend.sessionAffinityConfig.cookieSessionAffinity
)
if not changed then
return
end
self.cookie_session_affinity = backend.sessionAffinityConfig.cookieSessionAffinity
end
return _M