fix: apply changes for distributed vl3 dns after manual testing

pkg/networkservice/chains/nsmgr/vl3_test.go

@@ -68,7 +68,10 @@ func Test_NSC_ConnectsTo_vl3NSE(t *testing.T) {
 		nseReg,
 		sandbox.GenerateTestToken,
 		vl3.NewServer(ctx, serverPrefixCh),
-		vl3dns.NewServer(ctx, vl3dns.WithDomainSchemes("{{ index .Labels \"podName\" }}.{{ .NetworkService }}."), vl3dns.WithDNSPort(40053)),
+		vl3dns.NewServer(ctx,
+			func() net.IP { return net.ParseIP("127.0.0.1") },
+			vl3dns.WithDomainSchemes("{{ index .Labels \"podName\" }}.{{ .NetworkService }}."),
+			vl3dns.WithDNSPort(40053)),
 	)
 
 	resolver := net.Resolver{
@@ -95,7 +98,6 @@ func Test_NSC_ConnectsTo_vl3NSE(t *testing.T) {
 		require.NoError(t, err)
 		require.Len(t, resp.GetContext().GetDnsContext().GetConfigs(), 1)
 		require.Len(t, resp.GetContext().GetDnsContext().GetConfigs()[0].DnsServerIps, 1)
-		require.Equal(t, "10.0.0.0", resp.GetContext().GetDnsContext().GetConfigs()[0].DnsServerIps[0])
 
 		req.Connection = resp.Clone()
 
@@ -152,14 +154,22 @@ func Test_vl3NSE_ConnectsTo_vl3NSE(t *testing.T) {
 
 	serverPrefixCh <- &ipam.PrefixResponse{Prefix: "10.0.0.1/24"}
 
+	var dnsConfigs = new(vl3dns.Map)
+
 	_ = domain.Nodes[0].NewEndpoint(
 		ctx,
 		nseReg,
 		sandbox.GenerateTestToken,
 		vl3.NewServer(ctx, serverPrefixCh),
-		vl3dns.NewServer(ctx, vl3dns.WithDomainSchemes("{{ index .Labels \"podName\" }}.{{ .NetworkService }}."), vl3dns.WithDNSListenAndServeFunc(func(ctx context.Context, handler dnsutils.Handler, listenOn string) {
-			dnsutils.ListenAndServe(ctx, handler, ":50053")
-		}), vl3dns.WithDNSPort(40053)),
+		vl3dns.NewServer(ctx,
+			func() net.IP { return net.ParseIP("0.0.0.0") },
+			vl3dns.WithDomainSchemes("{{ index .Labels \"podName\" }}.{{ .NetworkService }}."),
+			vl3dns.WithDNSListenAndServeFunc(func(ctx context.Context, handler dnsutils.Handler, listenOn string) {
+				dnsutils.ListenAndServe(ctx, handler, ":50053")
+			}),
+			vl3dns.WithConfigs(dnsConfigs),
+			vl3dns.WithDNSPort(40053),
+		),
 	)
 
 	resolver := net.Resolver{
@@ -174,7 +184,7 @@ func Test_vl3NSE_ConnectsTo_vl3NSE(t *testing.T) {
 	defer close(clientPrefixCh)
 
 	clientPrefixCh <- &ipam.PrefixResponse{Prefix: "127.0.0.1/32"}
-	nsc := domain.Nodes[0].NewClient(ctx, sandbox.GenerateTestToken, client.WithAdditionalFunctionality(vl3.NewClient(ctx, clientPrefixCh)))
+	nsc := domain.Nodes[0].NewClient(ctx, sandbox.GenerateTestToken, client.WithAdditionalFunctionality(vl3dns.NewClient(net.ParseIP("127.0.0.1"), dnsConfigs), vl3.NewClient(ctx, clientPrefixCh)))
 
 	req := defaultRequest(nsReg.Name)
 	req.Connection.Id = uuid.New().String()
@@ -183,9 +193,8 @@ func Test_vl3NSE_ConnectsTo_vl3NSE(t *testing.T) {
 
 	resp, err := nsc.Request(ctx, req)
 	require.NoError(t, err)
-	require.Len(t, resp.GetContext().GetDnsContext().GetConfigs(), 1)
 	require.Len(t, resp.GetContext().GetDnsContext().GetConfigs()[0].DnsServerIps, 1)
-	require.Equal(t, "10.0.0.0", resp.GetContext().GetDnsContext().GetConfigs()[0].DnsServerIps[0])
+	require.Equal(t, "127.0.0.1", resp.GetContext().GetDnsContext().GetConfigs()[0].DnsServerIps[0])
 
 	require.Equal(t, "127.0.0.1/32", resp.GetContext().GetIpContext().GetSrcIpAddrs()[0])
 	req.Connection = resp.Clone()

pkg/networkservice/connectioncontext/dnscontext/vl3dns/client.go

@@ -0,0 +1,84 @@
+// Copyright (c) 2022 Cisco and/or its affiliates.
+//
+// SPDX-License-Identifier: Apache-2.0
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at:
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package vl3dns
+
+import (
+	"context"
+	"net"
+
+	"github.com/golang/protobuf/ptypes/empty"
+	"github.com/networkservicemesh/api/pkg/api/networkservice"
+	"google.golang.org/grpc"
+
+	"github.com/networkservicemesh/sdk/pkg/networkservice/core/next"
+)
+
+type vl3DNSClient struct {
+	dnsServerIP net.IP
+	dnsConfigs  *Map
+}
+
+// NewClient - returns a new null client that does nothing but call next.Client(ctx).{Request/Close} and return the result
+//             This is very useful in testing
+func NewClient(dnsServerIP net.IP, dnsConfigs *Map) networkservice.NetworkServiceClient {
+	return &vl3DNSClient{
+		dnsServerIP: dnsServerIP,
+		dnsConfigs:  dnsConfigs,
+	}
+}
+
+func (n *vl3DNSClient) Request(ctx context.Context, request *networkservice.NetworkServiceRequest, opts ...grpc.CallOption) (*networkservice.Connection, error) {
+	if request.GetConnection() == nil {
+		request.Connection = new(networkservice.Connection)
+	}
+	if request.GetConnection().GetContext() == nil {
+		request.GetConnection().Context = new(networkservice.ConnectionContext)
+	}
+	if request.GetConnection().GetContext().GetDnsContext() == nil {
+		request.GetConnection().GetContext().DnsContext = new(networkservice.DNSContext)
+	}
+
+	request.GetConnection().GetContext().GetDnsContext().Configs = []*networkservice.DNSConfig{
+		{
+			DnsServerIps: []string{n.dnsServerIP.String()},
+		},
+	}
+	resp, err := next.Client(ctx).Request(ctx, request, opts...)
+
+	if err == nil {
+		for _, config := range resp.GetContext().GetDnsContext().GetConfigs() {
+			var skip = false
+			for _, ip := range config.DnsServerIps {
+				if ip == n.dnsServerIP.String() {
+					skip = true
+					break
+				}
+			}
+			if skip {
+				continue
+			}
+			n.dnsConfigs.Store(resp.GetId(), config)
+		}
+	}
+
+	return resp, err
+}
+
+func (n *vl3DNSClient) Close(ctx context.Context, conn *networkservice.Connection, opts ...grpc.CallOption) (*empty.Empty, error) {
+	n.dnsConfigs.Delete(conn.GetId())
+	return next.Client(ctx).Close(ctx, conn, opts...)
+}

pkg/networkservice/connectioncontext/dnscontext/vl3dns/gen.go

@@ -0,0 +1,26 @@
+// Copyright (c) 2022 Cisco and/or its affiliates.
+//
+// SPDX-License-Identifier: Apache-2.0
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at:
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package vl3dns
+
+import (
+	"sync"
+)
+
+//go:generate go-syncmap -output map.gen.go -type Map<string,*github.com/networkservicemesh/api/pkg/api/networkservice.DNSConfig>
+
+// Map - sync.Map with key == string and value == networkservice.DNSConfig
+type Map sync.Map

pkg/networkservice/connectioncontext/dnscontext/vl3dns/options.go

@@ -19,7 +19,6 @@ package vl3dns
 import (
 	"context"
 	"fmt"
-	"net/url"
 	"text/template"
 
 	"github.com/networkservicemesh/sdk/pkg/tools/dnsutils"
@@ -28,10 +27,10 @@ import (
 // Option configures vl3DNSServer
 type Option func(*vl3DNSServer)
 
-// WithInitialFanoutList sets initial list to fanout queries
-func WithInitialFanoutList(initialFanoutList []url.URL) Option {
+// WithConfigs sets initial list to fanout queries
+func WithConfigs(m *Map) Option {
 	return func(vd *vl3DNSServer) {
-		vd.initialFanoutList = initialFanoutList
+		vd.configs = m
 	}
 }