From 6f7b66fc7d9f6238ca46c3dd21d4121f1e24cc1a Mon Sep 17 00:00:00 2001
From: Elvin Efendi <elvin.efendiyev@gmail.com>
Date: Fri, 26 Jul 2019 09:35:58 -0400
Subject: [PATCH] memoize balancer for a request

---
 rootfs/etc/nginx/lua/balancer.lua | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/rootfs/etc/nginx/lua/balancer.lua b/rootfs/etc/nginx/lua/balancer.lua
index e9fcb32bc..4388d4e89 100644
--- a/rootfs/etc/nginx/lua/balancer.lua
+++ b/rootfs/etc/nginx/lua/balancer.lua
@@ -190,6 +190,10 @@ local function route_to_alternative_balancer(balancer)
 end
 
 local function get_balancer()
+  if ngx.ctx.balancer then
+    return ngx.ctx.balancer
+  end
+
   local backend_name = ngx.var.proxy_upstream_name
 
   local balancer = balancers[backend_name]
@@ -201,8 +205,10 @@ local function get_balancer()
     local alternative_backend_name = balancer.alternative_backends[1]
     ngx.var.proxy_alternative_upstream_name = alternative_backend_name
 
-    return balancers[alternative_backend_name]
+    balancer = balancers[alternative_backend_name]
   end
+  
+  ngx.ctx.balancer = balancer
 
   return balancer
 end