Pull request #1558: add-dnssvc

Merge in DNS/adguard-home from add-dnssvc to master

Squashed commit of the following:

commit 55f4f114bab65a03c0d65383e89020a7356cff32
Merge: 95dc28d9 6e63757f
Author: Ainar Garipov <A.Garipov@AdGuard.COM>
Date:   Mon Aug 15 20:53:07 2022 +0300

    Merge branch 'master' into add-dnssvc

commit 95dc28d9d77d06e8ac98c1e6772557bffbf1705b
Author: Ainar Garipov <A.Garipov@AdGuard.COM>
Date:   Mon Aug 15 20:52:50 2022 +0300

    all: imp tests, docs

commit 0d9d02950d84afd160b4b1c118da856cee6f12e5
Author: Ainar Garipov <A.Garipov@AdGuard.COM>
Date:   Thu Aug 11 19:27:59 2022 +0300

    all: imp docs

commit 8990e038a81da4430468da12fcebedf79fe14df6
Author: Ainar Garipov <A.Garipov@AdGuard.COM>
Date:   Thu Aug 11 19:05:29 2022 +0300

    all: imp tests more

commit 92730d93a2a1ac77888c2655508e43efaf0e9fde
Author: Ainar Garipov <A.Garipov@AdGuard.COM>
Date:   Thu Aug 11 18:37:48 2022 +0300

    all: imp tests more

commit 8cd45ba30da7ac310e9dc666fb2af438e577b02d
Author: Ainar Garipov <A.Garipov@AdGuard.COM>
Date:   Thu Aug 11 18:11:15 2022 +0300

    all: add v1 dnssvc stub; refactor tests

internal/v1/dnssvc/dnssvc_test.go

@@ -0,0 +1,89 @@
+package dnssvc_test
+
+import (
+	"context"
+	"net/netip"
+	"testing"
+	"time"
+
+	"github.com/AdguardTeam/AdGuardHome/internal/aghtest"
+	"github.com/AdguardTeam/AdGuardHome/internal/v1/dnssvc"
+	"github.com/AdguardTeam/dnsproxy/upstream"
+	"github.com/miekg/dns"
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+)
+
+func TestMain(m *testing.M) {
+	aghtest.DiscardLogOutput(m)
+}
+
+// testTimeout is the common timeout for tests.
+const testTimeout = 100 * time.Millisecond
+
+func TestService(t *testing.T) {
+	const (
+		bootstrapAddr = "bootstrap.example"
+		upstreamAddr  = "upstream.example"
+	)
+
+	ups := &aghtest.UpstreamMock{
+		OnAddress: func() (addr string) {
+			return upstreamAddr
+		},
+		OnExchange: func(req *dns.Msg) (resp *dns.Msg, err error) {
+			resp = (&dns.Msg{}).SetReply(req)
+
+			return resp, nil
+		},
+	}
+
+	c := &dnssvc.Config{
+		Addresses:        []netip.AddrPort{netip.MustParseAddrPort("127.0.0.1:0")},
+		Upstreams:        []upstream.Upstream{ups},
+		BootstrapServers: []string{bootstrapAddr},
+		UpstreamServers:  []string{upstreamAddr},
+		UpstreamTimeout:  testTimeout,
+	}
+
+	svc, err := dnssvc.New(c)
+	require.NoError(t, err)
+
+	err = svc.Start()
+	require.NoError(t, err)
+
+	gotConf := svc.Config()
+	require.NotNil(t, gotConf)
+	require.Len(t, gotConf.Addresses, 1)
+
+	addr := gotConf.Addresses[0]
+
+	t.Run("dns", func(t *testing.T) {
+		req := &dns.Msg{
+			MsgHdr: dns.MsgHdr{
+				Id:               dns.Id(),
+				RecursionDesired: true,
+			},
+			Question: []dns.Question{{
+				Name:   "example.com.",
+				Qtype:  dns.TypeA,
+				Qclass: dns.ClassINET,
+			}},
+		}
+
+		ctx, cancel := context.WithTimeout(context.Background(), testTimeout)
+		defer cancel()
+
+		cli := &dns.Client{}
+		resp, _, excErr := cli.ExchangeContext(ctx, req, addr.String())
+		require.NoError(t, excErr)
+
+		assert.NotNil(t, resp)
+	})
+
+	ctx, cancel := context.WithTimeout(context.Background(), testTimeout)
+	defer cancel()
+
+	err = svc.Shutdown(ctx)
+	require.NoError(t, err)
+}