Support logging to dnstap in forward plugin (#2703)

plugin/forward/dnstap_test.go

@@ -0,0 +1,63 @@
+package forward
+
+import (
+	"context"
+	"testing"
+	"time"
+
+	"github.com/coredns/coredns/plugin/dnstap"
+	"github.com/coredns/coredns/plugin/dnstap/msg"
+	"github.com/coredns/coredns/plugin/dnstap/test"
+	mwtest "github.com/coredns/coredns/plugin/test"
+	"github.com/coredns/coredns/request"
+
+	tap "github.com/dnstap/golang-dnstap"
+	"github.com/miekg/dns"
+)
+
+func testCase(t *testing.T, f *Forward, q, r *dns.Msg, datq, datr *msg.Builder) {
+	tapq, _ := datq.ToOutsideQuery(tap.Message_FORWARDER_QUERY)
+	tapr, _ := datr.ToOutsideResponse(tap.Message_FORWARDER_RESPONSE)
+	tapper := test.TrapTapper{}
+	ctx := dnstap.ContextWithTapper(context.TODO(), &tapper)
+	err := toDnstap(ctx, "10.240.0.1:40212", f,
+		request.Request{W: &mwtest.ResponseWriter{}, Req: q}, r, time.Now())
+	if err != nil {
+		t.Fatal(err)
+	}
+	if len(tapper.Trap) != 2 {
+		t.Fatalf("Messages: %d", len(tapper.Trap))
+	}
+	if !test.MsgEqual(tapper.Trap[0], tapq) {
+		t.Errorf("Want: %v\nhave: %v", tapq, tapper.Trap[0])
+	}
+	if !test.MsgEqual(tapper.Trap[1], tapr) {
+		t.Errorf("Want: %v\nhave: %v", tapr, tapper.Trap[1])
+	}
+}
+
+func TestDnstap(t *testing.T) {
+	q := mwtest.Case{Qname: "example.org", Qtype: dns.TypeA}.Msg()
+	r := mwtest.Case{
+		Qname: "example.org.", Qtype: dns.TypeA,
+		Answer: []dns.RR{
+			mwtest.A("example.org. 3600	IN	A 10.0.0.1"),
+		},
+	}.Msg()
+	tapq, tapr := test.TestingData(), test.TestingData()
+	fu := New()
+	fu.opts.preferUDP = true
+	testCase(t, fu, q, r, tapq, tapr)
+	tapq.SocketProto = tap.SocketProtocol_TCP
+	tapr.SocketProto = tap.SocketProtocol_TCP
+	ft := New()
+	ft.opts.forceTCP = true
+	testCase(t, ft, q, r, tapq, tapr)
+}
+
+func TestNoDnstap(t *testing.T) {
+	err := toDnstap(context.TODO(), "", nil, request.Request{}, nil, time.Now())
+	if err != nil {
+		t.Fatal(err)
+	}
+}