remove global dnscache

remove global dnscache

main.go

@@ -81,10 +81,6 @@ const (
 	profilingPath         = "/.pprof"
 )
 
-var dnsCache = &dnscache.Resolver{
-	Timeout: 5 * time.Second,
-}
-
 func init() {
 	// Create a new instance of the logger. You can have any number of instances.
 	log2 = logrus.New()
@@ -647,10 +643,11 @@ type roundTripperWrapper struct {
 }
 
 func (rtw *roundTripperWrapper) renew() {
-	dnsCache.Refresh()
 	tr := &http.Transport{
-		Proxy:                 http.ProxyFromEnvironment,
-		DialContext:           dialContextWithDNSCache(dnsCache, newProxyDialContext(10*time.Second)),
+		Proxy: http.ProxyFromEnvironment,
+		DialContext: dialContextWithDNSCache(&dnscache.Resolver{
+			Timeout: 5 * time.Second,
+		}, newProxyDialContext(10*time.Second)),
 		MaxIdleConnsPerHost:   1024,
 		WriteBufferSize:       32 << 10, // 32KiB moving up from 4KiB default
 		ReadBufferSize:        32 << 10, // 32KiB moving up from 4KiB default
@@ -929,15 +926,6 @@ func sidekickMain(ctx *cli.Context) {
 		globalHostBalance = "least"
 	}
 
-	go func() {
-		t := time.NewTicker(ctx.GlobalDuration("dns-ttl"))
-		defer t.Stop()
-
-		for range t.C {
-			dnsCache.Refresh()
-		}
-	}()
-
 	if !strings.HasPrefix(healthCheckPath, slashSeparator) {
 		healthCheckPath = slashSeparator + healthCheckPath
 	}