Metrics: track the use of TCP vs. UDP

Why implement a feature w/out measuring how much it gets used?

I want to know who, if anyone, is using TCP queries.

TODO: update the documentation.

src/sslip.io-dns-server/integration_metrics_test.go

@@ -20,22 +20,35 @@ var _ = Describe("IntegrationMetrics", func() {
 			var actualMetrics xip.Metrics
 			expectedMetrics := getMetrics(port)
 
-			// A updates .Queries, .AnsweredQueries, .AnsweredAQueries
+			// A updates .Queries, UDPQueries .AnsweredQueries, .AnsweredAQueries
 			expectedMetrics.Queries++
+			expectedMetrics.UDPQueries++
 			expectedMetrics.AnsweredQueries++
 			expectedMetrics.AnsweredAQueries++
 			expectedMetrics = bumpExpectedToAccountForMetricsQuery(expectedMetrics)
 			actualMetrics = digAndGetMetrics("@localhost 127.0.0.1.sslip.io +short -p "+strconv.Itoa(port), port)
 			Expect(expectedMetrics.MostlyEquals(actualMetrics)).To(BeTrue())
 
+			// A updates .Queries, TCPQueries .AnsweredQueries, .AnsweredAQueries
+			expectedMetrics.Queries++
+			expectedMetrics.TCPQueries++
+			expectedMetrics.AnsweredQueries++
+			expectedMetrics.AnsweredAQueries++
+			expectedMetrics = bumpExpectedToAccountForMetricsQuery(expectedMetrics)
+			// "+vc" runs the lookup over TCP, not UDP
+			actualMetrics = digAndGetMetrics("@localhost 127.0.0.1.sslip.io +short +vc -p "+strconv.Itoa(port), port)
+			Expect(expectedMetrics.MostlyEquals(actualMetrics)).To(BeTrue())
+
 			// A (non-existent) record updates .Queries
 			expectedMetrics.Queries++
+			expectedMetrics.UDPQueries++
 			expectedMetrics = bumpExpectedToAccountForMetricsQuery(expectedMetrics)
 			actualMetrics = digAndGetMetrics("@localhost non-existent.sslip.io +short -p "+strconv.Itoa(port), port)
 			Expect(expectedMetrics.MostlyEquals(actualMetrics)).To(BeTrue())
 
 			// A blocked updates .Queries, .AnsweredQueries, .AnsweredBlockedQueries
 			expectedMetrics.Queries++
+			expectedMetrics.UDPQueries++
 			expectedMetrics.AnsweredQueries++
 			expectedMetrics.AnsweredBlockedQueries++
 			expectedMetrics = bumpExpectedToAccountForMetricsQuery(expectedMetrics)
@@ -45,6 +58,7 @@ var _ = Describe("IntegrationMetrics", func() {
 
 			// AAAA updates .Queries, .AnsweredQueries, .AnsweredAAAAQueries
 			expectedMetrics.Queries++
+			expectedMetrics.UDPQueries++
 			expectedMetrics.AnsweredQueries++
 			expectedMetrics.AnsweredAAAAQueries++
 			expectedMetrics = bumpExpectedToAccountForMetricsQuery(expectedMetrics)
@@ -53,12 +67,14 @@ var _ = Describe("IntegrationMetrics", func() {
 
 			// AAAA (non-existent) updates .Queries
 			expectedMetrics.Queries++
+			expectedMetrics.UDPQueries++
 			expectedMetrics = bumpExpectedToAccountForMetricsQuery(expectedMetrics)
 			actualMetrics = digAndGetMetrics("@localhost non-existent.sslip.io aaaa +short -p "+strconv.Itoa(port), port)
 			Expect(expectedMetrics.MostlyEquals(actualMetrics)).To(BeTrue())
 
 			// MX (customized) updates .Queries, .AnsweredQueries
 			expectedMetrics.Queries++
+			expectedMetrics.UDPQueries++
 			expectedMetrics.AnsweredQueries++
 			expectedMetrics = bumpExpectedToAccountForMetricsQuery(expectedMetrics)
 			actualMetrics = digAndGetMetrics("@localhost sslip.io mx +short -p "+strconv.Itoa(port), port)
@@ -66,6 +82,7 @@ var _ = Describe("IntegrationMetrics", func() {
 
 			// MX updates .Queries, AnsweredQueries
 			expectedMetrics.Queries++
+			expectedMetrics.UDPQueries++
 			expectedMetrics.AnsweredQueries++
 			expectedMetrics = bumpExpectedToAccountForMetricsQuery(expectedMetrics)
 			actualMetrics = digAndGetMetrics("@localhost non-existent.sslip.io mx +short -p "+strconv.Itoa(port), port)
@@ -73,6 +90,7 @@ var _ = Describe("IntegrationMetrics", func() {
 
 			// NS updates .Queries, AnsweredQueries
 			expectedMetrics.Queries++
+			expectedMetrics.UDPQueries++
 			expectedMetrics.AnsweredQueries++
 			expectedMetrics = bumpExpectedToAccountForMetricsQuery(expectedMetrics)
 			actualMetrics = digAndGetMetrics("@localhost non-existent.sslip.io ns +short -p "+strconv.Itoa(port), port)
@@ -80,6 +98,7 @@ var _ = Describe("IntegrationMetrics", func() {
 
 			// NS DNS-01 challenge record updates .Queries, .AnsweredNSDNS01ChallengeQueries
 			expectedMetrics.Queries++
+			expectedMetrics.UDPQueries++
 			// DNS-01 challenges don't count as successful because we're not authoritative; we're delegating
 			expectedMetrics.AnsweredNSDNS01ChallengeQueries++
 			expectedMetrics = bumpExpectedToAccountForMetricsQuery(expectedMetrics)
@@ -88,6 +107,7 @@ var _ = Describe("IntegrationMetrics", func() {
 
 			// Always successful: SOA
 			expectedMetrics.Queries++
+			expectedMetrics.UDPQueries++
 			expectedMetrics.AnsweredQueries++
 			expectedMetrics = bumpExpectedToAccountForMetricsQuery(expectedMetrics)
 			dig("@localhost non-existent.sslip.io soa +short -p " + strconv.Itoa(port))
@@ -96,6 +116,7 @@ var _ = Describe("IntegrationMetrics", func() {
 
 			// TXT sslip.io (customized) updates .Queries, .AnsweredQueries,
 			expectedMetrics.Queries++
+			expectedMetrics.UDPQueries++
 			expectedMetrics.AnsweredQueries++
 			expectedMetrics = bumpExpectedToAccountForMetricsQuery(expectedMetrics)
 			actualMetrics = digAndGetMetrics("@localhost sslip.io txt +short -p "+strconv.Itoa(port), port)
@@ -103,12 +124,14 @@ var _ = Describe("IntegrationMetrics", func() {
 
 			// TXT sslip.io (non-existent) updates .Queries, .AnsweredQueries,
 			expectedMetrics.Queries++
+			expectedMetrics.UDPQueries++
 			expectedMetrics = bumpExpectedToAccountForMetricsQuery(expectedMetrics)
 			actualMetrics = digAndGetMetrics("@localhost non-existent.sslip.io txt +short -p "+strconv.Itoa(port), port)
 			Expect(expectedMetrics.MostlyEquals(actualMetrics)).To(BeTrue())
 
 			// TXT ip.sslip.io updates .Queries, .AnsweredQueries, .AnsweredTXTSrcIPQueries
 			expectedMetrics.Queries++
+			expectedMetrics.UDPQueries++
 			expectedMetrics.AnsweredQueries++
 			expectedMetrics.AnsweredTXTSrcIPQueries++
 			expectedMetrics = bumpExpectedToAccountForMetricsQuery(expectedMetrics)
@@ -117,6 +140,7 @@ var _ = Describe("IntegrationMetrics", func() {
 
 			// TXT version.sslip.io updates .Queries, .AnsweredQueries, .AnsweredTXTVersionQueries
 			expectedMetrics.Queries++
+			expectedMetrics.UDPQueries++
 			expectedMetrics.AnsweredQueries++
 			expectedMetrics.AnsweredTXTVersionQueries++
 			expectedMetrics = bumpExpectedToAccountForMetricsQuery(expectedMetrics)
@@ -125,6 +149,7 @@ var _ = Describe("IntegrationMetrics", func() {
 
 			// PTR version.sslip.io updates .Queries, .AnsweredQueries, .AnsweredPTRQueriesIPv4
 			expectedMetrics.Queries++
+			expectedMetrics.UDPQueries++
 			expectedMetrics.AnsweredQueries++
 			expectedMetrics.AnsweredPTRQueriesIPv4++
 			expectedMetrics = bumpExpectedToAccountForMetricsQuery(expectedMetrics)
@@ -133,6 +158,7 @@ var _ = Describe("IntegrationMetrics", func() {
 
 			// PTR version.sslip.io updates .Queries, .AnsweredQueries, .AnsweredPTRQueriesIPv6
 			expectedMetrics.Queries++
+			expectedMetrics.UDPQueries++
 			expectedMetrics.AnsweredQueries++
 			expectedMetrics.AnsweredPTRQueriesIPv6++
 			expectedMetrics = bumpExpectedToAccountForMetricsQuery(expectedMetrics)
@@ -141,6 +167,7 @@ var _ = Describe("IntegrationMetrics", func() {
 
 			// TXT DNS-01 challenge record updates .Queries, .AnsweredNSDNS01ChallengeQueries
 			expectedMetrics.Queries++
+			expectedMetrics.UDPQueries++
 			expectedMetrics.AnsweredNSDNS01ChallengeQueries++
 			expectedMetrics = bumpExpectedToAccountForMetricsQuery(expectedMetrics)
 			actualMetrics = digAndGetMetrics("@localhost _acme-challenge.fe80--.sslip.io txt +short -p "+strconv.Itoa(port), port)
@@ -154,6 +181,7 @@ var _ = Describe("IntegrationMetrics", func() {
 // the Heisenberg uncertainty principle (observing changes the values)
 func bumpExpectedToAccountForMetricsQuery(metrics xip.Metrics) xip.Metrics {
 	metrics.Queries++
+	metrics.UDPQueries++
 	metrics.AnsweredQueries++
 	return metrics
 }
@@ -181,6 +209,7 @@ func getMetrics(port int) (m xip.Metrics) {
 		"\"Uptime: %d\"\n"+
 			"\"Blocklist: %s %s %s\n"+
 			"\"Queries: %d (%s\n"+ // %s "swallows" the `/s"` at the end
+			"\"TCP/UDP: %d/%d\"\n"+
 			"\"Answered Queries: %d (%s\n"+ // %s "swallows" the `/s"` at the end
 			"\"A: %d\"\n"+
 			"\"AAAA: %d\"\n"+
@@ -192,6 +221,7 @@ func getMetrics(port int) (m xip.Metrics) {
 		&uptime,
 		&junk, &junk, &junk,
 		&m.Queries, &junk,
+		&m.TCPQueries, &m.UDPQueries,
 		&m.AnsweredQueries, &junk,
 		&m.AnsweredAQueries,
 		&m.AnsweredAAAAQueries,

src/sslip.io-dns-server/main.go

@@ -130,6 +130,7 @@ func readFromUDP(conn *net.UDPConn, x *xip.Xip, quiet bool) {
 			if !quiet {
 				log.Printf("%v.%d %s", addr.IP, addr.Port, logMessage)
 			}
+			x.Metrics.UDPQueries += 1
 		}()
 	}
 }
@@ -167,6 +168,7 @@ func readFromTCP(tcpListener *net.TCPListener, x *xip.Xip, quiet bool) {
 			if !quiet {
 				log.Printf("%s.%s %s", addr, port, logMessage)
 			}
+			x.Metrics.TCPQueries += 1
 		}()
 	}
 }

src/sslip.io-dns-server/xip/xip.go

@@ -37,6 +37,8 @@ type Xip struct {
 type Metrics struct {
 	Start                           time.Time
 	Queries                         int
+	TCPQueries                      int
+	UDPQueries                      int
 	AnsweredQueries                 int
 	AnsweredAQueries                int
 	AnsweredAAAAQueries             int
@@ -892,6 +894,7 @@ func TXTMetrics(x *Xip, _ net.IP) (txtResources []dnsmessage.TXTResource, err er
 		len(x.BlocklistStrings),
 		len(x.BlocklistCDIRs)))
 	metrics = append(metrics, fmt.Sprintf("Queries: %d (%.1f/s)", x.Metrics.Queries, float64(x.Metrics.Queries)/uptime.Seconds()))
+	metrics = append(metrics, fmt.Sprintf("TCP/UDP: %d/%d", x.Metrics.TCPQueries, x.Metrics.UDPQueries))
 	metrics = append(metrics, fmt.Sprintf("Answered Queries: %d (%.1f/s)", x.Metrics.AnsweredQueries, float64(x.Metrics.AnsweredQueries)/uptime.Seconds()))
 	metrics = append(metrics, fmt.Sprintf("A: %d", x.Metrics.AnsweredAQueries))
 	metrics = append(metrics, fmt.Sprintf("AAAA: %d", x.Metrics.AnsweredAAAAQueries))
@@ -920,6 +923,8 @@ func soaLogMessage(soaResource dnsmessage.SOAResource) string {
 // MostlyEquals compares all fields except `Start` (timestamp)
 func (a Metrics) MostlyEquals(b Metrics) bool {
 	if a.Queries == b.Queries &&
+		a.TCPQueries == b.TCPQueries &&
+		a.UDPQueries == b.UDPQueries &&
 		a.AnsweredQueries == b.AnsweredQueries &&
 		a.AnsweredAQueries == b.AnsweredAQueries &&
 		a.AnsweredAAAAQueries == b.AnsweredAAAAQueries &&