Remove duplicate dns configs in response connection in DNSContextClie…

…nt (#1318) * remove duplicate dns configs in response Signed-off-by: Nikita Skrynnik <nikita.skrynnik@xored.com> * fix linter Signed-off-by: Nikita Skrynnik <nikita.skrynnik@xored.com> * delete metadata + add removeDuplicates before request Signed-off-by: Nikita Skrynnik <nikita.skrynnik@xored.com> * fix linter Signed-off-by: Nikita Skrynnik <nikita.skrynnik@xored.com> * check intersections + add removeDuplicates test Signed-off-by: Nikita Skrynnik <nikita.skrynnik@xored.com> * add dns configs check on dnsContextServer Signed-off-by: Nikita Skrynnik <nikita.skrynnik@xored.com> * fix ci Signed-off-by: Nikita Skrynnik <nikita.skrynnik@xored.com> * fix Test_DNSContextClient_Usecases Signed-off-by: Nikita Skrynnik <nikita.skrynnik@xored.com> * rework dns configs check in dnsContextServer Signed-off-by: Nikita Skrynnik <nikita.skrynnik@xored.com> * fix Test_DNSUsecase Signed-off-by: Nikita Skrynnik <nikita.skrynnik@xored.com>
networkservicemesh · Jul 12, 2022 · 65679c0 · 65679c0
1 parent 454062d
commit 65679c0
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Showing 3 changed files with 57 additions and 5 deletions.
diff --git a/pkg/networkservice/chains/nsmgr/single_test.go b/pkg/networkservice/chains/nsmgr/single_test.go
@@ -47,7 +47,7 @@ import (
 func Test_DNSUsecase(t *testing.T) {
 	t.Cleanup(func() { goleak.VerifyNone(t) })
 
-	ctx, cancel := context.WithTimeout(context.Background(), time.Second*5)
+	ctx, cancel := context.WithTimeout(context.Background(), time.Second*7)
 	defer cancel()
 
 	domain := sandbox.NewBuilder(ctx, t).

diff --git a/pkg/networkservice/connectioncontext/dnscontext/client.go b/pkg/networkservice/connectioncontext/dnscontext/client.go
@@ -154,10 +154,14 @@ func (c *dnsContextClient) initialize() {
 
 	c.storeOriginalResolvConf()
 
-	c.resolvconfDNSConfig = &networkservice.DNSConfig{
-		SearchDomains: r.Value(dnscontext.AnyDomain),
-		DnsServerIps:  r.Value(dnscontext.NameserverProperty),
+	nameserver := r.Value(dnscontext.NameserverProperty)
+	if !containsNameserver(nameserver, c.defaultNameServerIP) {
+		c.resolvconfDNSConfig = &networkservice.DNSConfig{
+			SearchDomains: r.Value(dnscontext.AnyDomain),
+			DnsServerIps:  nameserver,
+		}
 	}
+
 	c.dnsConfigManager.Store("", c.resolvconfDNSConfig)
 
 	r.SetValue(dnscontext.NameserverProperty, c.defaultNameServerIP)
@@ -169,3 +173,13 @@ func (c *dnsContextClient) initialize() {
 
 	c.updateCorefileQueue.AsyncExec(c.updateCorefile)
 }
+
+func containsNameserver(servers []string, value string) bool {
+	for i := range servers {
+		if servers[i] == value {
+			return true
+		}
+	}
+
+	return false
+}
diff --git a/pkg/networkservice/connectioncontext/dnscontext/server.go b/pkg/networkservice/connectioncontext/dnscontext/server.go
@@ -1,5 +1,7 @@
 // Copyright (c) 2020-2021 Doc.ai and/or its affiliates.
 //
+// Copyright (c) 2022 Cisco and/or its affiliates.
+//
 // SPDX-License-Identifier: Apache-2.0
 //
 // Licensed under the Apache License, Version 2.0 (the "License");
@@ -43,10 +45,46 @@ func (d *dnsContextServer) Request(ctx context.Context, request *networkservice.
 	if request.GetConnection().GetContext().GetDnsContext() == nil {
 		request.GetConnection().GetContext().DnsContext = new(networkservice.DNSContext)
 	}
-	request.GetConnection().GetContext().GetDnsContext().Configs = append(request.GetConnection().GetContext().GetDnsContext().Configs, d.configs...)
+
+	for _, config := range d.configs {
+		if !contains(request.GetConnection().GetContext().GetDnsContext().Configs, config) {
+			request.GetConnection().GetContext().GetDnsContext().Configs = append(request.GetConnection().GetContext().GetDnsContext().Configs, config)
+		}
+	}
 	return next.Server(ctx).Request(ctx, request)
 }
 
 func (d *dnsContextServer) Close(ctx context.Context, conn *networkservice.Connection) (*empty.Empty, error) {
 	return next.Server(ctx).Close(ctx, conn)
 }
+
+func contains(array []*networkservice.DNSConfig, value *networkservice.DNSConfig) bool {
+	for i := range array {
+		if equal(array[i].DnsServerIps, value.DnsServerIps) && equal(array[i].SearchDomains, value.SearchDomains) {
+			return true
+		}
+	}
+	return false
+}
+
+func equal(a, b []string) bool {
+	if len(a) != len(b) {
+		return false
+	}
+
+	diff := make(map[string]int, len(a))
+	for _, v := range a {
+		diff[v]++
+	}
+
+	for _, v := range b {
+		if _, ok := diff[v]; !ok {
+			return false
+		}
+		diff[v]--
+		if diff[v] == 0 {
+			delete(diff, v)
+		}
+	}
+	return len(diff) == 0
+}