flush all cached dns between tests

Author: neerfri

rootfs/etc/nginx/lua/balancer.lua

@@ -123,7 +123,7 @@ local function sync_backend(backend)
     balancers[backend.name] = nil
     return
   end
-  print("Syncing backend: ", backend.name, "with endpoints: ", cjson.encode(backend.endpoints))
+  print("\nSyncing backend: ", backend.name, "with endpoints: ", cjson.encode(backend.endpoints))
 
   backend.endpoints = format_ipv6_endpoints(backend.endpoints)
 

rootfs/etc/nginx/lua/test/balancer_test.lua

@@ -1,5 +1,6 @@
 local cjson = require("cjson.safe")
 local util = require("util")
+local dns_cache = require("util.dns").__index._cache
 
 local balancer, expected_implementations, backends
 local original_ngx = ngx
@@ -96,6 +97,7 @@ describe("Balancer", function()
     reset_balancer()
     reset_expected_implementations()
     reset_backends()
+    dns_cache.flush_all()
   end)
 
   after_each(function()